UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

Seasonal isolation and adaptation among chum salmon, Oncorhynchus keta (Walbaum), populations Tallman, Ross Franklin 1988

Your browser doesn't seem to have a PDF viewer, please download the PDF to view this item.

Item Metadata

Download

Media
831-UBC_1989_A1 T34.pdf [ 13.66MB ]
Metadata
JSON: 831-1.0098366.json
JSON-LD: 831-1.0098366-ld.json
RDF/XML (Pretty): 831-1.0098366-rdf.xml
RDF/JSON: 831-1.0098366-rdf.json
Turtle: 831-1.0098366-turtle.txt
N-Triples: 831-1.0098366-rdf-ntriples.txt
Original Record: 831-1.0098366-source.json
Full Text
831-1.0098366-fulltext.txt
Citation
831-1.0098366.ris

Full Text

SEASONAL ISOLATION AND ADAPTATION AMONG CHUM SALMON, Oncorhynchus k e t a (Walbaum), POPULATIONS by ROSS FRANKLIN TALLMAN B. S c . , The U n i v e r s i t y o f M a n i t o b a , 1977 M. S c . , The U n i v e r s i t y o f M a n i t o b a , 1980 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS OF THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE STUDIES (Department o f Z o o l o g y , I n s t i t u t e o f A n i m a l Resource E c o l o g y )  We a c c e p t t h i s t h e s i s as c o n f o r m i n g to the required standard  THE UNIVERSITY OF BRITISH COLUMBIA O c t o b e r 1988 © R o s s F r a n k l i n T a l l m a n , 1988  In  presenting  degree freely  this  at the  thesis  in  University of  available for reference  copying  of  department publication  this or of  thesis for by  this  his  or  partial fulfilment  of  British  I agree  Columbia,  and study. scholarly her  the  requirements that the  I further agree  purposes  representatives.  may be It  thesis for financial gain shall not  is  that  an  permission for extensive  granted  by the  allowed  that  head  of  my  copying  or  without  permission.  Source The University of British Columbia Vancouver, Canada  DE-6 (2/88)  advanced  Library shall make it  understood be  for  my written  i i  ABSTRACT  To  test  the  hypothesis  that  temporal  isolation  due  to  differences in  i  season  of  breeding  populations, genotypic  I  could  result  compared  performances  the  of  from stock  one  Vancouver  (W)  All  Island  These were stream  season  autumn  (Bush  Creek)  similar  of fry migration.  found  The  time  among the W  WB  size,  In  external  1982,  WB  and  test  the  ecotypes  populations  significantly  fry.  in  the  that  wild  of  i n age  WB  under the autumn - winter early  more time t o hatch  the  due  spawners  winter  spawning  of  the  fry.  at m a t u r i t y ,  fry  AB  No  length  f r y and  spawners.  revealed  time and AB  Analysis  of  there  was  that  to  similarities genetic  observed  among  differences,  sample  c o n d i t i o n s i n the  laboratory.  When  - s p r i n g p r o g r e s s i o n and the w i n t e r  spawning and  chum  spawners were l a r g e r than  phenotypic  were  of  stocks.  under c o n t r o l l e d  the  another  and  from the other s t o c k s i n egg s i z e  In 1981,  features  hypothesis  progression,  stocks  salmon  (WB)  v e r t e b r a l count of a d u l t s and  i n body form o f the  were reared  r e a r e d at 6°C,  AB  stocks  winter  migration  spawners were younger than  morphological  considerable overlap  and  stock d i f f e r e d  v e r t e b r a l number o f a d u l t s and spawners.  of  and  chum  phenotypes  breeding  (AB)  downstream  had  o f spawners, egg  spring  late  stocks  composition  seasonal  and  among  environments,  Creek).  were  To  divergence  from a nearby stream (Walker  differences  ten  genetic  reproductive  early  salmon, Oncorhynchus k e t a .  in  population  emerge than  in  Bush  the s p a t i a l l y  and  Creek  -  took  temporally  i i i  isolated  population  of  spawning p o p u l a t i o n s .  Temperature interaction  At  10°C  regime,  a l l had  spawning  Creek,  population  distinct  population  and  the  combined  the p o p u l a t i o n s  significant  were m o r p h o l o g i c a l l y early  Walker  and  effects  from WB  similar  temperature on  and  differs  had  average  of  regime  These r e s u l t s  genetically  from  late  incubation rates.  by  v e r t e b r a l number.  W.  the  population AB  progrency  i n d i c a t e that  the  late  the  spawning  populations.  To  test  the  fertilization variation  hypothesis  to  hatch  i n these  Heritabilities  and  traits,  were  that  s e l e c t i o n on  emergence  individual  found  to  be  would  the  speed o f development  reduce  the  additive  f a m i l i e s were r e a r e d between  0.27  from AB,  and  genetic WB  0.54.  from  and  The  W.  high  h e r i t a b i l i t i e s suggest t h a t some c o u n t e r v a i l i n g f o r c e i s opposing s e l e c t i o n on incubation rate.  Analysis  of d i v e r s i t y  genetic migration  using biochemical  goes from the  WB  stock  to  genetics techniques the  AB  stock.  suggest  Genetic  measures and  a Wagner-Tree a n a l y s i s i n d i c a t e t h a t b i o c h e m i c a l l y AB  more c l o s e l y  r e l a t e d than  It which  i s postulated results  Survival  could  resources  i n the  distance  and  WB  are  W.  that  the  g e n e t i c a l l y determined  in  synchronous  downstream  be  enhanced  predator  estuary.  that  by  program  migration satiation  has or  for  incubation  survival  synchrony  with  value. food  iv  TABLE OF CONTENTS  ABSTRACT  i i  LIST OF TABLES  vi  LIST OF FIGURES  xvii  LIST OF APPENDICES  xxii  ACKNOWLEDGEMENTS  xxvi  INTRODUCTION  1  S e l e c t i o n and the E c o l o g y o f Chum Salmon The D i s t r i b u t i o n and Abundance o f Seasonal Races and  15 Speculations  Regarding T h e i r E v o l u t i o n a r y O r i g i n Review Phenotypic D i f f e r e n t a t i o n among Seasonal E c o t y p e s o f Chum Salmon  30 30 41  Introduction  41  M a t e r i a l s and Methods  46  Results Discussion  6  2  94  V  Innate versus E n v i r o n m e n t a l C o n t r o l o f Phenotypes among Seasonal Ecotypes  116  Introduction  116  M a t e r i a l s and Methods  119  Results  130  Discussion  191  Evidence f o r S e l e c t i o n on I n c u b a t i o n  Rate  204  Introduction  204  M a t e r i a l s and Methods  205  Results  206  Discussion  .  An E l e c t r o p h o r e t i c A n a l y s i s o f G e n e t i c  V a r i a t i o n Among  206 Seasonally  Separated P o p u l a t i o n s  210  Introduction  211  M a t e r i a l s and Methods  214  Results  224  Discussion  Summary and S y n t h e s i s  LITERATURE  APPENDICES  CITED  •  of Empirical Findings  238  248  271  294  vi  LIST OF TABLES  Table  1.  Mean dates  of s t a r t ,  peak  and end o f Bush  and Walker  Creek  chum spawning runs from 1969 t o 1981  Table  2.  Comparisons axes  between  AB=Autumn  populations  Bush  Population;  49  along  spatial  WB=Winter  and temporal  Bush  Population;  W=Walker P o p u l a t i o n  Table  3.  The y e a r l y median distribution  49  and mode  ( i n Julian  day) o f the temporal  o f a d u l t s on the Bush and Walker Creek spawning  grounds d u r i n g 1981 and 1982  Table 4.  S u r v i v a l time o f a d u l t s distribution  65  i n freshwater  o f counts o f l i v e  at p e r c e n t i l e s o f the  and dead  adults  during  1981  and 1982  Table  5.  Vertebral  65  counts  deviations  of  1982  spawners:  (SD), and sample  sizes  means  (X), standard  stratified  by p o p u l a t i o n ,  sex and age  Table 6.  Single  degress  differences (MSD  67  =  of  freedom  comparisons  among p o p u l a t i o n s  Minimum  Significant  d i f f e r e n c e s P = .05)  using  of  vertebral  the Tukey-Kramer  Difference)  (*  count Method.  significant 68  vii  Table  7.  Age at r e t u r n deviations  f o r 1981 and 1982 spawners.  and sample  sizes  Means, s t a n d a r d  of populations s t r a t i f i e d  by  sex  Table  8.  68  O r b i t - H y p u r a l P l a t e Lengths o f 1981 and 1982 spawners: (50,  means  s t a n d a r d d e v i a t i o n s (SD), and sample s i z e s s t r a t i f i e d by  p o p u l a t i o n , sex and age  Table  9.  Single  degree  populations  of  using  Significant  70  freedom the  comparisons  Tukey-Kramer  D i f f e r e n c e - MSD.  among  spawning  Method.  (* s i g n i f i c a n t  Minimum difference,  P = .05)  Table 10.  71  Capture e f f i c i e n c y o f i n c l i n e d p l a n e t r a p s below t h e spawning areas d u r i n g 1983  Table 11.  73  The y e a r l y median and mode ( i n J u l i a n distribution  o f f r y e m i g r a t i n g from  day) o f t h e temporal  Bush and Walker  Creeks  d u r i n g 1982 and 1983  T a b l e 12.  Vertebral  counts  76  f o r f r y m i g r a t i n g downstream d u r i n g 1982.  Means, s t a n d a r d d e v i a t i o n s stratified  by  time.  and sample s i z e s  F r y samples  c o r r e s p o n d i n g t o t h e approximate  were  of populations  made  at  intervals  17th, 33rd, 50th, 6 7 t h , and  83rd p e r c e n t i l e s o f t h e c u m u l a t i v e frequency d i s t r i b u t i o n o f i n d i v i d u a l s w i t h time  76  viii  Table 13.  V e r t e b r a l counts Means,  standard  stratified  by  Variables  to of  individuals  Table 14.  d e v i a t i o n s and time.  corresponding percentiles  for fry migrating  Fry  the  the  downstream  sample s i z e s  samples  approximate  cumulative  were  of  made  25th,  during  populations at  50th  frequency  1983.  intervals and  distribution  75th of  w i t h time  entered  f u n c t i o n s ranked  by  78  into  the  1982  and  1983  discriminant  importance w i t h c l a s s i f i c a t i o n f u n c t i o n s  f o r each  Table  15.  78  Classification  matrix  for  1982  fry  samples  using  the  discriminant function  Table  16.  Classification  matrix  79  for  1983  fry  samples  using  the  discriminant function  Table  17.  Approximate  79  transformation  F  statistic  comparing  group  c e n t r o i d s f o r 1982  Table  18.  Mahalanobis  distance  81  between  population  centroids  for  1982  Table  19.  Approximate  81  transformation  c e n t r o i d s among 1983 progeny  F  statistic  comparing  group 81  ix  Table 20. Mahalanobis  distance  between  population  centroids  for  1983  81  Table 21. Means  and  standard  characteristics Weight  deviations  o f 1982 f r y samples.  i s i n 0.1gm.  of  morphological  Lengths a r e i n 0.1mm.  (S.M. Mean s t a n d a r d i z e d  t o a common  l e n g t h among t h e samples)  Table 22. Means  and  82  standard  deviations  c h a r a c t e r i s t i c s o f 1983 f r y samples.  of  morphological  (S.M. Mean s t a n d a r d i z e d  to a common l e n g t h among t h e samples)  Table  23. C l a s s i f i c a t i o n  matrix  f o r 1983  83  f r y samples  using  the  d i s c r i m i n a n t f u n c t i o n from t h e 1982 d a t a  Table 24. Comparisons  o f accumulated  d a t a ) and i n c u b a t i o n times  ^4  degree-days  (raw and  adjusted  ( a c t u a l and p r e d i c t e d ) f o r AB, WB,  and W s t o c k s i n 1981-82 and 1982-83.  ( c a l c u l a t e d from median  day o f t h e a d u l t and f r y runs)  Table  25. S i n g l e  degree  differences the  of  freedom  among p o p u l a t i o n s  GT2 Method.  87  comparisons adjusted  of  for covariate  (MSD = Minimum S i g n i f i c a n t  (* s i g n i f i c a n t d i f f e r e n c e P = .05)  egg  weight using  Difference) 92  X  Table 26.  The temporal and s p a t i a l  p a t t e r n o f r e t u r n o f marked f i s h t o  Bush and Walker Creeks d u r i n g 1984 and 1985  93  Table 27.  Return r a t e o f marked f i s h  93  Table 28.  Mean water temperatures  T a b l e 29.  i n each c e l l  f o r 1982-83 and 1983-84  experiments.  (Standard D e v i a t i o n i n P a r e n t h e s i s )  Orbit-hypural  plate  length  124  o f females and egg s i z e s  used i n  1982-83 and 1983-84 experiments  Table 30.  Mean  hatch  treatments  t i  m  e  for  139  population  i n 1983-84 experiment.  by  temperature  regime  (Standard d e v i a t i o n s a r e  i n parentheses)  Table 31.  Results hatch  140  o f comparisons among  temperature  the  regime.  and c o n t r a s t s  test  populations  Mean time  time  two p o p u l a t i o n s t o the r i g h t .  (An a s t e r i s k  <  0.05.  Two  within  asterisks  each  i n comparisons  o f the minus s i g n the p o p u l a t i o n  P  50 % hatch  t o 50 %  A p l u s (+) i n d i c a t e s  than  that  t o reach  t o the l e f t  reared  t o hatch used  was a d j u s t e d f o r temperature v a r i a t i o n . that the population  o f mean time  (**)  took  more  or average o f (*)  indicates  indicate  that  xi  Table 32.  Mean  emergence  treatments  time  f o r population  i n 1982-83 experiment.  by  temperature  regime  (Standard d e v i a t i o n s are  i n parentheses)  Table 33.  Mean  151  emergence  treatments  time  for population  i n 1983-84 experiment.  by  temperature  regime  (Standard d e v i a t i o n s are  i n parentheses)  Table 34.  Results  o f comparisons  emergence  among  temperature comparisons (+) sign  151  population asterisk  test  regime.  o f mean  populations  Mean  time  that  more  the p o p u l a t i o n  time  or average  (*)  to  reach  time  reared  to  50  %  each  used  variation.  t o the l e f t  to 50 %  within  emergence  was a d j u s t e d f o r temperature  indicates took  the  and c o n t r a s t s  A plus  o f the minus  emergence  than  o f two p o p u l a t i o n s to the r i g h t .  indicates  that  P < 0.05.  Two  in  asterisks  the (An (**)  i n d i c a t e t h a t P < 0.01)  T a b l e 35.  Summary  o f the number  152  of significant  comparisons  u s i n g the  SSSTP ( G a b r i e l 1964) pooled over a l l temperature regimes  Table 36.  Survival  o f chum  salmon  f o r each  population,  regime, tank and year d u r i n g d i f f e r e n t development from f e r t i l i z a t i o n  154  temperature  segments o f embryonic  t o emergence. (1)  156  xii  Table 37.  Mean  vertebral  treatments  counts  for population  i n 1983-84  experiment.  by  temperature  (Standard  regime  d e v i a t i o n s are  i n parentheses, N = 50)  Table 38.  174  Approximate t r a n s f o r m a t i o n  F statistic  to compare  population  c e n t r o i d s with a l l temperatures pooled  T a b l e 39.  Mahalanobis  distance  between  176  population  centroids  1983  samples  with a l l  temperatures pooled  Table 40.  Classification discriminant  Table 41.  Table 43.  matrix  using  the  for laboratory  f r y samples  178  using  the  for laboratory  178  f r y samples  using  the  f u n c t i o n at 10 C e l s i u s  matrix  for laboratory  179  f r y samples  using  the  f u n c t i o n at E a r l y Regime  Classification discriminant  fry  function at 6 C e l s i u s  Classification discriminant  T a b l e 44.  matrix  Classification discriminant  for  f u n c t i o n a l l temperatures pooled  Classification discriminant  Table 42.  matrix  matrix  for laboratory  f u n c t i o n at Late Regime  179  f r y samples  using  the 180  xi i i  Table 45.  Approximate  transformation  F statistic  to compare  population  c e n t r o i d s at 6 C e l s i u s  Table 46.  Mahalanobis  distance  180  between  population  centroids  at  6  Celsius  Table 47.  Approximate  180  transformation  F statistic  t o compare  population  c e n t r o i d s at 10 C e l s i u s  Table 48.  Mahalanobis  distance  180  between  population  centroids  at  10  Celsius  Table 49.  Approximate  181  transformation  F statistic  t o compare  population  c e n t r o i d s at E a r l y Regime  Table 50.  Mahalanobis  distance  181  between  population  centroids  at E a r l y  Regime  Table 51.  Approximate  181  transformation  F statistic  t o compare  population  c e n t r o i d s at L a t e Regime  Table 52.  Mahalanobis Regime  distance  between  181  population  centroids  at  Late 181  xiv  Table 53.  Means  and  characteristics 1983-84.  standard  deviations  o f emergent  of  f r y reared  (S.M. Mean s t a n d a r d i z e d  morphological  at 6 C e l s i u s  t o a common  length  during among  the samples)  Table 54.  Means  and  characteristics  182  standard  deviations  o f emergent  of  morphological  f r y r e a r e d a t 10 C e l s i u s  during  1983-84 (S.M. Mean s t a n d a r d i z e d t o a common l e n g t h among t h e samples)  Table 55.  Means  185  and  standard  deviations  of  morphological  c h a r a c t e r i s t i c s o f emergent f r y r e a r e d under the E a r l y Regime during  1983-84  (S.M. Mean  standardized  t o a common  length  among the samples)  Table 56.  Means  and  characteristics during  187  standard  deviations  o f emergent  1983-84 (S.M. Mean  of  f r y reared  standardized  under  morphological Late  Regime  t o a common  length  among t h e samples)  Table 57.  Heritabilities  and lower  189  confidence  limit  (LCL) (P = 0.05)  f o r time t o 50 % hatch at 8°C  Table 58.  Heritabilities  and lower  confidence  f o r time t o 50 % emergence at 8°C  207  limit  (LCL) (P = 0.05) 207  XV  Table 59.  Enzymes  within  tissues  and  buffer  systems  used  i n the  electrophoretic analysis  Table 60.  Sample used  Table 61.  sizes,  215  and allozyme  frequencies  o f polymorphic  loci  i n the a n a l y s i s  Heterozy  gosity  225  and t e s t  o f comformance t o t o Hardy-Weinberg  e q u i l i b r i u m o f polymorphic  loci  w i t h i n each p o p u l a t i o n  Table 62.  Summary o f F - s t a t i s t i c s  at a l l l o c i  Table 63.  Contingency  at  chi-square  probability  231  233  a l l loci.  Chi-square  and  v a l u e s f o r the h y p o t h e s i s t h a t samples were drawn  from the same p o p u l a t i o n  Table 64.  Estimates  of e f f e c t i v e  235  population  size  f o r each  population  u s i n g the a l g e b r a i c mean, harmonic mean and m o d i f i e d harmonic mean methods d e s c r i b e d i n t h e t e x t  Table 65.  Probability migrant  that  individual  a  randomly assuming  chosen  236  allele  random mating,  will  be  from  a  no s e l e c t i o n , or  mutation  Table 66.  Genetic  237  d i s t a n c e and g e n e t i c i d e n t i t y  diagonal:  Rogers  (1972) Genetic  "D"  Identity  (Wright  1978).  over  a l lloci:  ABOVE  diagonal:  BELOW Nei 240  xvi  Table 67.  Genetic  distance  Distance  over  (Wright  a l lloci:  1978).  BELOW  diagonal:  ABOVE d i a g o n a l :  Prevosti  Nei (1972) G e n e t i c  distance  Table  68.  2  Genetic  distance  Cavalli-Sforza diagonal:  Table 69.  Genetic  Genetic  and Edwards  distance  diagonal:  70.  all  loci:  (1967)  BELOW  Chord  over  and  a l l loci:  Edwards  (1967)  distance.  ABOVE 240  BELOW  diagonal:  arc distance.  ABOVE  Nei (1972) Minimum d i s t a n c e  distance  over  a l lloci:  BELOW  241  diagonal:  Edwards  (1971, 1974) "E" d i s t a n c e  Table  71. M a t r i x  of  coefficients  single-locus  0  diagonal:  Nei (1978) Unbiased Minimum D i s t a n c e  Cavalli-Sforza  Table  over  4  241  genetic  similarity  or  distance 242  xvi i  LIST OF FIGURES  F i g u r e 1.  S e r i a l and b r a n c h i n g e v o l u t i o n  11  F i g u r e 2.  World d i s t r i b u t i o n o f chum salmon  16  F i g u r e 3.  A model o f chum salmon between s e l e c t i o n  life  history  showing t h e i n t e r a c t i o n  ( S ) , genotype (G) and environment (E)  F i g u r e 4.  Bush and Walker c r e e k s :  F i g u r e 5.  D i s t a n c e between  27  the study area  spawning groups o f chum salmon  47  i n Bush and  Walker Creeks  F i g u r e 6.  Timing o f spawning  50  i n Walker Creek and t h e upper and lower  s e c t i o n o f t h e spawning 1982. day.  Number o f l i v e  a r e a i n Bush Creek d u r i n g spawners  1981 and  observed v e r s u s the J u l i a n  Median day o f each run shown by arrow  63  F i g u r e 7.  D i e l t i m i n g o f emergence o f f r y from AB, WB and W  72  F i g u r e 8.  Timing o f f r y downstream m i g r a t i o n s from Walker Creek and t h e upper and lower s e c t i o n s o f the spawning a r e a i n Bush during  1982 and 1983.  Creek  Number o f f r y c a p t u r e d i n i n c l i n e d  p l a i n t r a p s v e r s u s t h e J u l i a n day  75  xvi i i  ure  9.  Temperature during  and  flow p r o f i l e s  1981-82 and  1982-83.  Open c i r c l e s = Walker  ure 10.  Egg  development  (post-August  31,  from  Bush  and  Closed c i r c l e s  Walker  Creeks  = Bush  Creek;  Creek  stage 1981)  (Velsen f o r AB  and  1980) W.  versus  log  day  bars  are  length  of  Horizontal  p r o p o r t i o n a l t o the number o f eggs at each stage  ure 11.  Egg  weight  versus  spawners from Walker o f the spawning  ure 12.  female  Creek and the upper  graphical  vertebral  count program  WB,  and  circles  = AB,  indicate count  the  plate and  lower  a r e a i n Bush Creek d u r i n g 1981  Proposed  AB,  orbit-hypural  W  model  during  of  1978-79,  response  of  temperature progeny  1981-82.  Triangles  from  = WB.  determining "EARLY"  ....  between  of incubation  1979-80,  = W,  and 1982  interaction  and temperature  Closed c i r c l e s critical  the  sections  among Open Arrows  vertebral  and  "LATE"  and  1983-84  spawners  ure 13.  Incubation  temperatures  experiments.  Solid  temperature regime  lines  (C)  of  the  1982-83  r e p r e s e n t the planned changes  in •  xi x  F i g u r e 14.  Time  t o hatch  under  6°C,  10°C, s i m u l a t e d  regime, s i m u l a t e d w i n t e r spawning W x WB  Figure  15.  Time  regime  t o hatch  W x WB  W, and  under  6°C,  10°C, s i m u l a t e d regime  autumn  spawning  f o r AB, WB,  135  Time t o emergence under 6°C, 10°C, s i m u l a t e d autumn regime  spawning  f o r AB, WB,  W, and  i n the 1982-83 experiment  .142  Time t o emergence under 6°C, 10°C, s i m u a l t e d autumn regime, W x WB  simulated  w i n t e r spawning  regime  spawning  f o r AB, WB,  W and  i n the 1983-84 experiment  146  S u r v i v a l under 6°C, 10°C, s i m u l a t e d s i m u l a t e d w i n t e r spawning the  W, and  i n the 1983-84 experiment  W x WB  F i g u r e 18.  f o r AB, WB,  131  regime, s i m u l a t e d w i n t e r spawning  F i g u r e 17.  spawning  i n the 1982-83 experiment  regime, s i m u l a t e d w i n t e r spawning  F i g u r e 16.  autumn  1982-83  autumn spawning  regime f o r AB, WB,  experiment  from  regime,  W and W x WB i n  fertilization  to  epiboly,  e p i b o l y eyed and eyed t o hatch  F i g u r e 19.  158  S u r v i v a l under 6°C, 10°C, s i m u l a t e d simulated in  w i n t e r spawning  the 1983-84  experiment  regime from  e p i b o l y t o eyed and eyed t o hatch  autumn spawning  f o r AB, WB, fertilization  W,  regime,  and W x WB to  epiboly, 162  XX  F i g u r e 20.  S u r v i v a l under 6°C, 10°C, s i m u l a t e d s i m u l a t e d w i n t e r spawning i n the 1982-83 experiment to  F i g u r e 21.  regime  f o r AB, WB,  from f e r t i l i z a t i o n  emergence, and f e r t i l i z a t i o n  the  1983-84 experiment  regime  and W x WB  t o h a t c h , hatch  f  o  165  autumn spawning r  regime,  AB, WB, W and W x WB i n  from f e r t i l i z a t i o n  emergence, and f e r t i l i z a t i o n  W,  regime,  t o emergence  S u r v i v a l under 6°C, 10°C, s i m u l a t e d s i m u l a t e d winter spawning  F i g u r e 22.  autumn spawning  t o h a t c h , hatch t o  to emergence  170  Schematic drawings t o show the body form o f progeny WB,  and  W  rearings  from  6°C  treatment  of  from AB,  the  1983-84  experiment  F i g u r e 23.  ^83  Schematic drawings t o show the body form o f progeny WB,  and  W  rearings  from  10°C  treatment  of  from AB,  the  1983-84  experiment  F i g u r e 24.  Schematic drawings t o show the body form o f progeny WB, of  F i g u r e 25.  186  and W r e a r i n g s from s i m u l a t e d  autumn spawning  of  treatment  the 1983-84 experiment  Schematic drawings t o show the body form o f progeny WB,  from AB,  and W r e a r i n g s from s i m u l a t e d w i n t e r spawning the 1983-84 experiment  188  from AB, treatment 190  xxi  F i g u r e 26.  Pathways f o r Gene flow among AB, WB and W  F i g u r e 27.  Genetic  similarity  using  Nei's  (1978)  220  unbiased  genetic  similarity  F i g u r e 28.  239  Wagner Tree produced (base measure used  F i g u r e 29.  Barriers  to  by r o o t i n g at midpoint  Prevosti  crossmating  o f l o n g e s t path  D i s t a n c e [Wright 1978])  showing  the  g e n e t i c m i g r a t i o n ( A f t e r Mayr 1970)  cumulative  effect  243  on 258  xxi i  LIST OF APPENDICES  Appendix  1.  Analysis  of  population and  variance  and  emergence  tables  temperature during  the  estimating  regime 1982-83  the  f o r mean and  effect  time  1983-84  of  to hatch incubation  experiments  Appendix  2.  Comparisons time  to  1983-84  294  and c o n t r a s t s among means o f time t o hatch and  emergence  of  experiment.  embryos  reared  Calculation  SS-STP Test C. V. = (a - 1) x MSW  Appendix  3.  G-tests  o f independence  epiboly  o f embryos  of  during  the  Appendix  4.  and egg s i z e  G-tests  of  pigment  stage  effects  of  embryos  temperature,  l o c a t i o n o f spawning  Value  for  from  alpha  fertilization  1982-83 from  the  to  effects  location of 304  independence of  and  a(n-1),  o f temperature, p o p u l a t i o n , season o f spawning, spawning  1982-83  Critical  x F (a-1),  of s u r v i v a l  reared  in  of  survival  reared  during  population,  and egg s i z e  from  epiboly 1982-83  season  of  to  eye  from  the  spawning, 310  xxi i i  Appendix  5.  G-test to  o f independence o f s u r v i v a l  hatch o f embryos r e a r e d  during  from eye  pigment  1982-83 from the  o f temperature, p o p u l a t i o n , season o f spawning,  G-tests  o f independence o f s u r v i v a l  hatch o f embryos r e a r e d temperature,  effects  location of  i  spawning and egg s i z e  Appendix 6.  stage  during  population,  from  316  fertilization  to  1982-83 from the e f f e c t s of  season  of  spawning,  location  of  spawning and egg s i z e  Appendix 7.  G-tests of  322  o f independence o f s u r v i v a l  embryos  temperature,  reared  during  population,  from hatch to emergence  1982-83  season  of  from  the  spawning,  effects  of  location  of  spawning and egg s i z e  Appendix 8.  G-tests  o f independence  epiboly  o f embryos  328  of survival  reared  during  from  fertilization  1983-84 from the  to  effects  o f temperature, p o p u l a t i o n , season o f spawning, l o c a t i o n  of  spawning and egg s i z e  Appendix 9.  independence  334  G-tests  of  pigment  stage o f  effects  of  location  o f spawning and egg s i z e  embryos  temperature,  of  survival  reared  from  during  population,  epiboly  1983-84  season  of  to  eye  from  the  spawning, 340  xxi v  Appendix 10.  G - t e s t s o f independence o f s u r v i v a l  from eye pigment stage  hatch o f embryos r e a r e d d u r i n g 1983-84 from the e f f e c t s of temperature,  population,  season o f spawning,  location  of  spawning and egg s i z e  Appendix  11.  346  G - t e s t s o f independence o f s u r v i v a l  from f e r t i l i z a t i o n  to  hatch o f embryos r e a r e d d u r i n g 1983-84 from the e f f e c t s o f temperature,  population,  season o f spawning,  location  of  spawning and egg s i z e  Appendix 12.  G-tests  of  emergence effects location  Appendix 13.  independence  of  of  352  embryos  reared  survival during  temperature, p o p u l a t i o n ,  from 1983-84  season  of  hatch  to  from  the  spawning,  o f spawning and egg s i z e  Comparisons and c o n t r a s t s of  of  progeny  from  the  358  among means o f v e r t e b r a l  1983-84  experiment  using  counts  Scheffe's  method  364  Appendix 14.  P o p u l a t i o n s i z e e s t i m a t e d by s u r v i v a l time and f i s h - d a y s  .  366  Appendix 15.  Temperature changes (planned) i n l a b o r a t o r y experiments ..  368  XXV  Appendix  16.  Egg  sizes  and  size  of  females  used  in  laboratory  experiments  Appendix  17.  Water  temperatures  370  in relation  t o month  streams u t i l i z e d by chum salmon s t o c k s  and l a t i t u d e i n 372  xxvi  ACKNOWLEDGEMENTS  I wish  to  thank  my  supervisor,  T.G.  and  support throughout the  the  P a c i f i c B i o l o g i c a l S t a t i o n i n Naniaimo, B.C.  fish the  f o r the  project.  Bob  Northcote,  breeding experiments.  P a c i f i c Biological Station  Ball,  T.D.  and  C.  Ted  of  University plan  and  CC.  Lindsey,  of B r i t i s h  the  thesis.  approaches t o my the  In  Busack of the  bizarre  results. and  F i n a l l y , I extend  P a c i f i c B i o l o g i c a l Station  revolutionized  Project  scholarship,  thinking  investigation.  honesty d u r i n g  Canada.  my  my  was and  constructive  and  T.P.  criticism  by I  who  formally thank  as  my  him  for  the  Department  me  of  supervisory  Walters on  the  of  the  research  thank C C .  on  to  some o f my  to M.C.  kindness,  the  Wood  of  o f Washington  co-supervisor.  introducing his  My  University  warmest a p p r e c i a t i o n  served  Riddell  to e x p l o r e some novel  commented i n c i t e f u l l y  my  B.  of M i s s i s s i p p i  C.J.  especially  Quinn o f the  c o l l e c t i o n of  and  the p r o j e c t .  Myers  of  more  Healey Dr.  of  Healey  philosophy  intelligence,  of and  education.  expenses I  J.  I wish t o  l i s t e n e d p a t i e n t l y and  ideas.  scientific  McPhail,  advice  Clyde Murray  University  many cases they c h a l l e n g e d me  i d e a s and  and  Beacham, R. W i t h l e r  Columbia gave me  Pacific Biological Station  i n S e a t t l e who  the  J.D.  Carter,  valuable  helped with the  p r o v i d e d h e l p f u l a d v i c e at d i f f e r e n t times d u r i n g committee  for his  were p a i d  supported a University  by  financially  by  an  of  Fisheries  N.S.E.R.C.  of B r i t i s h Columbia Research  and  Oceans,  post-graduate  Fellowship.  1  INTRODUCTION  The c l a s s i c a l and a p p a r e n t l y most widespread mechanism o f i n t e r p o p u l a t i o n differentiation by  virtue  i s through  of their  differentially  the r e d u c t i o n o f gene flow between two p o p u l a t i o n s  geographic  on each  isolation  isolated  gene  a d a p t a t i o n s t o the l o c a l environmental as  the a l l o p a t r i c  adaptation  adaptive genetic divergence than  i n space  (Carson  pool  Alexander  and Templeton  and Bigelow  c o n s t r a i n t s on the l i f e would r e s u l t a  resulting  or s p e c i a t i o n model.  i s through  history  seasonal  cycle  1984).  diverse  separated  taxonomic  of field  1984), i n s e c t s (Alexander Tauber 1987)  and Tauber and f i s h e s  s e a s o n a l ecotypes grasslands.  cricket  isolated  in A p r i l ,  and l i v e s  i s when a  seasons or y e a r s . seasonal  species  For  environmental  i n temperate  zones  p o p u l a t i o n s adapted to They  coined  the  term  situation.  populations  have  been  reported  in  and Roughgarden  and Bigelow 1960, Naraoka 1987, Tauber et a l . 1977,  1959).  amphibians An  example  o f Hemizonia l u z u l i f o l i a ,  One form  specific  T h i s i s known  of this  as f l o w e r i n g p l a n t s ( C h i a r e l l o  1976, 1981), (Berg  that  reproduction.  reproductive  groups such  acts  Another p o s s i b l e mode o f  in different  " a l l o c h r o n i c " a d a p t a t i o n or s p e c i a t i o n f o r t h i s  Seasonally  i n population  An example  (1960) proposed  of  Selection  i s o l a t i o n o f p o p u l a t i o n s i n time r a t h e r  i n the development o f t e m p o r a l l y  particular  1981).  c o n d i t i o n s (Mayr 1963).  s p e c i e s has s e p a r a t e p o p u l a t i o n s breeding example,  (Templeton  (subspecies  until  early  (Blair  1941),  reptiles  i n the flowering an annual  luzuli folia)  (Mendonca  plants  i s the  p l a n t o f the C a l i f o r n i a  germinates  summer, whereas the other  i n winter, (subspecies  flowers rudis)  2  germinates  i n winter  but f l o w e r s  i n midsummer, and o f t e n l i v e s  autumn ( C h i a r e l l o and Roughgarden 1984).  have been s t u d i e d e x t e n s i v e l y : t h e lacewings  both  there  isolated exists to  species  while  ( H a r r i s o n 1985).  maturity  differ  pennsylvanicus. thought southern  Temporal  as  The  which  at other  i s the  timing  at some  isolation  may occur  between  o f the onset  c y c l e s i n Chrysopa  latitudes  diapause  i s short  seasons  result  Mating the  i s lengthened  i n the "Chrysopa  "Chrysopa c o r n u t a  (Tauber  and  Tauber  downesi  type"  1982).  Tauber  termination  and s e a s o n a l  group  occurs  firmus  during et  rates  Gryllus  o f diapause  is  and Tauber 1982).  In  isolation  seasons  breaks  long.  down.  In  c o n s t r a i n t s are more s e v e r e ,  and b r e e d i n g occurs  In  of overlap  and  i n d u r a t i o n and b r e e d i n g  i n each  type"  zone  when development  (Tauber  the n o r t h e r n l a t i t u d e s the s e a s o n a l environmental diapause  crickets.  a c t as s e a s o n a l l y  hybrid  Gryllus  and  seasonal  breeding  latitudes  a broad  to c o n t r o l  Overlapping  and t h e f i e l d  latitudes  case  early  In the I n s e c t a t h e r e are two groups  that  are s p e c i e s complexes  until  seasons  during A p r i l  June t o August  a l . (1977)  do not o v e r l a p . whereas mating i n  and i n e a r l y  proposed  that  March  seasonal  i s o l a t i o n o f these types o c c u r r e d as a r e s u l t o f changes at o n l y two l o c i .  Interpopulation  variation  i n season  f a m i l i e s o f temperate zone f i s h e s reproductive Cyprinidae,  populations Belonidae  P i z z o r n o 1985).  and  in  o f reproduction  (Berg 1959).  the  Percidae  i n several  There a r e s e a s o n a l l y s e p a r a t e d  Petromyzontidae, (Neave  occurs  1949,  Clupeidae, Berg  1959,  Salmonidae, Goldberg  and  3  Several differ  researchers  with  separate  respect  gene  Studies  to  pools  the c l a i m of l i m i t e d 1981,  their  (Smith  o f polymorphic  Salmenkova  have  suggested seasonal  1969,  that  salmonid  timing  Berg  of  1934,  reproduction  1959,  enzymes among s e a s o n a l l y  Okazaki  distinct  gene flow among s e a s o n a l l y separated  Altukov  1981,  Okazaki  1978).  populations  For  found  chum salmon spawning  t h a t the l a t e r  populations  spawning run was  nearby l a t e spawning p o p u l a t i o n than stream.  Okazaki  (1978)  of  the  populations  support  stocks  example,  that  the  were  reproductively  physiological  and  number among w i n t e r in British among the the  and  two  reproductive  trout  f o r the there  traits  fishes  work o f Smith  is little  among salmonid  The  comparative has  existed  focussed  under  (1969) on  study the  of  et  reproducing  seasonally  adult  Japan.  phase  i n the same  population  had  runs w i t h i n  the  and  f a t storage trout  (1984)  and  summer  genetic  that  that  partial  steelhead  trout.  races  of  steelhead  divergence  in  polygenic  during d i f f e r e n t  life  maintained  indicating  found  winter  raker  (Salmo g a i r d n e r i )  conditions  and  the  gill  c h a r a c t e r s were  separated of  He  as  summer  regarding  seasonally  differences in  al.  winter  (1978)  (1969) recorded  controlled  between  populations  on  such  Leider  information  River,  t h a t the two  D i f f e r e n c e s i n these  inherited.  of two  spawning  summer migrants o f s t e e l h e a d  groups when r e a r e d  isolation  Smith  characters  Columbia streams.  d i f f e r e n c e s were  Except  isolated.  structural  Okazaki  and  i n enzyme f r e q u e n c i e s to a  late  a r i s e n from t r a n s p l a n t s from the other stream and stream  (Altukov  the e a r l y spawning p o p u l a t i o n  postulated  as  1981).  Tokachi  more s i m i l a r  function 1978,  compared the e l e c t r o p h o r e t i c p a t t e r n s at s e v e r a l enzyme l o c i separated  which  spawning cycle.  seasons.  populations However,  of the  4  ecological history  stages.  feeding at  consequences  a l l o c h r o n y may  Vladimirov  is a critical  t h i s time due  of  (1975)  be  proposed  p e r i o d o f development  to d e f e c t s i n t h e i r  and a s s i m i l a t i o n o f food organisms.  at  time  feeding.  of  the  Concurrently,  avoidence 1987).  Perfectly  predators proposed  formed  when t h e r e  present  as  well  Consequentially,  selective  particular 1979). showed (1980)  For  on form  is a  was as  some  l a r v a l m i g r a t i o n and  appear  in fish  the to  start  larvae.  the  Healey  still  l a c k of and  to  yolk  researchers  by  Houston  F i s h may with  and  the  cause  convergent  i f they  1987).  food  Recently, species  optimal  that  there  Rutberg  i n order  the  nursery  a particular  successful young  that  salmon  to  there  (1979) and  chum salmon f r y m i g r a t i o n s  (Godin  was  1982,  released  maturity an  Sibert  Miller  at  (Bilton optimal  and  Fresh  different 1980,  (1979) found  that  i n the e s t u a r y .  the  1982).  the  year  times  of  of annual  Fry  with  a  Healey the  1980).  corresponded  post  are under  1982,  time  reduce  of  al.  Taylor  yearly  i n the Nanimo R i v e r , B.C.  d e n s i t i e s o f t h e i r p r e f e r r e d food type  et  (1987)  to  timing  of  are  conditions.  Brannon  time  Main  embryonic  or  environmental  suggested  active  (Kneib 1987,  complete  exogenous  1982,  be  search,  p r e d a t i o n can  c o n s t r a i n t s (Godin grounds at  perish  of  i n ruminant  have  exogenous  start  perish  with  of  life  the  sufficient  coincide  early  e a r l y l i f e h i s t o r y morphs o f j u v e n i l e salmonids  example,  proposed  may  the  In Salmonidae, t h i s p e r i o d occurs  pressure  synchronized  variable survival  migration.  fry  (MacNamara  that b i r t h  predation  must  r e s o r p t i o n of  selection  the  t a c t i c s i n prey b e l o n g i n g to widely d i v e r g e n t taxa  development  seasonal  final  that  during  organ systems connected  capture the  greatest  year Bilton  downstream timing  of  t o the peak  5  A l l o c h r o n y c o m p l i c a t e s t h e development o f a c o h e s i v e phenotype whose form and  behaviour  a r e "tuned"  t o the environmental  conditions.  Consider  two  p o p u l a t i o n s o f e c t o t h e r m i c organisms:  one r e p r o d u c i n g d u r i n g the s p r i n g , t h e  other  months.  reproducing  during  population  must  to  The o f f s p r i n g  warm.  then  t h e summer  develop  is  However, i f t h e r e example,  t h e progeny  rising  start  from  cool  development  at a  p r o c e s s e s , dependent  of the early  time  to begin  c o n s t r a i n t on t h e l i f e  winter  h i b e r n a t i o n , both  a c t on t h e e x p r e s s i o n o f t h e t r a i t  be  time.  history, for groups  may  s e l e c t e d t o converge i n p h y s i o l o g i c a l s t a t e and stage o f development. genes c o n t r o l l i n g t h e t r a i t  It  group w i l l  than those o f t h e l a t e group at any p a r t i c u l a r  i s also a seasonal  an o p t i m a l  of the f i r s t  vary between p o p u l a t i o n s as a r e s u l t .  to envision that  somewhat more developed  population  are  The r a t e s o f developmental  of incubation, w i l l  not d i f f i c u l t  temperatures  o f t h e second  p l a t e a u o f warm t e m p e r a t u r e s . on temperature  while  The o f f s p r i n g  be  I f the  i n an a d d i t i v e  f a s h i o n , t h e e f f e c t on t h e g e n e t i c c o m p o s i t i o n o f t h i s c u t - o f f p o i n t w i l l , be similar  to a  population composition,  truncation  i s selected  experiment  i n opposite  s e l e c t e d t o conform  under s t a b i l i z i n g  that  selection  (Falconer  directions.  to a single  However,  optimum, w i l l  the be  each  phenotypic effectively  selection.  Pacific  salmon have adapted t o a l a r g e v a r i e t y o f spawning environments  differ  i n many ways, e.g. annual  p a t t e r n s o f water f l o w ,  i n s o l a t i o n , g r a v e l s i z e s , d i s t a n c e from t h e ocean, e t c . s t o c k t o an environment loci  1981) where  which c o n t r o l  i s probably  certain  temperature,  The a d a p t a t i o n o f a  a f f e c t e d by t h e s e l e c t i o n o f a l l e l e s at  key f i t n e s s  traits  o f the stock  such  as  annual  6  t i m i n g o f spawning, t h e temperature dependent development timing  o f emergence  appropriate stock  nest  i s at  controlling selection, sockeye  of  sites.  least  loci,  salmon  the s i z e  due  to  these t r a i t s  t h e stock  additive  to colonize  60 years ago Mendenhall G l a c i e r covered  it  is likely  National  Marine  Fisheries  rapid.  changes  i n existing  lifted  land  altering stocks  around  new environments. Lake  According  Auke  Prince  F o r example,  Williams  o f many  chum  but most o f these  t o J.H. H e l l e  Sound, and pink  stocks  near  altered  landscape. these  Pink  areas.  temperate  the i n t e r t i d a l  and chum salmon  I t seems  ectotherms,  such  seasons as t h e progeny develop  i n different  logical  have both that  developed  genetic  as salmonids,  start  development  thermal  conditions  that  Although, t o J.H.  the stock  comm.,  adaptation t o adapt t o  i n 1964 an earthquake Alaska, salmon  substantially (fj. gorbuscha) and a r e very  two major 20 y e a r s .  adaptation intertidal  land These  t o a new spawning i n  adaptations  should  evolve i n  reproduce  during  different  at d i f f e r e n t (that  Alaska;  pers.  have endured  and f o r c e d  the  to natural  Juneau,  ( p e r s . comm.) at l e a s t  areas  in  at the  (According  e l e v a t i o n changes have o c c u r r e d with earthquakes i n t h e l a s t apparently  of  For example,  Bay, A l a s k a ,  can a l s o allow  habitats.  habitat  (Noerenberg, 1971)  productive.  variability  i n t h e Mendenhall R i v e r i n 1922 and 1951)  spawning  t h e spawning  traits  those spawning grounds.  Service,  The v a r i a b i l i t y  masses  the choosing  fitness  man-made i n t r o d u c t i o n s a r e r e s p o n s i b l e  sockeye f r y were p l a n t e d must have been  genetic  o f Mendenhall  yet  Helle  o f these  or  can r e a d i l y change i n response  spawn i n t r i b u t a r i e s  that  o f eggs,  I f the v a r i a b i l i t y  partly  then  allowing  larvae,  r a t e o f embryos and  times  i s during  o f the y e a r , and  different  seasonal  7  cycles).  Many t r a i t s are s e n s i t i v e t o the temperature o f i n c u b a t i o n and t h e r e  may be s e l e c t i v e c o n s t r a i n t s on the e x p r e s s i o n  The  possibility  divergence evolution  among  that  populations  but a l s o  This  of  not  f o r the more  f i s h e r i e s management. "stock".  season  reproduction  only  has  i s a theoretical  traits.  i s important  implications  practical  In p a r t i c u l a r ,  o f these  efforts  made  i n genetic  f o r the study  of  i n the s c i e n c e  of  i t may broaden the working d e f i n i t i o n o f  construct  used  in a l l fisheries  management  efforts.  Larkin tool  the " s t o c k  f o r f i s h e r i e s management e f f o r t s .  1981)  as a group  authors of  (1972) i n t r o d u c e d  the  of fishes  have emphasized ecological  and  that  form  the u t i l i t y genetic  concept"  as a v a l u a b l e  A s t o c k may  be d e f i n e d  a unit  A  grand  represents 1981).  effort  has  been  characteristics  a d i s c r e t e stock  made  to  or management  of  towards  Helle,  Subsequent conservation  commercially  exploited  and Lannan 1986).  define, unit  in practical (Ihssen  terms,  1976, Ihssen  what  et a l .  Stocks have been d e s c r i b e d on the b a s i s o f e c o l o g i c a l d i f f e r e n c e s such  as the d i s t a n c e from t h e s e a o f the spawning grounds.  As w e l l ,  physiological  differ  (Taylor  (sensu  i n time and space.  o f the s t o c k concept  s p e c i e s (Harlan 1981, H e l l e 1981, Kapuscinski  theoretical  and  and McPhail  behavioural  1985, R i d d e l l  have been bounded by t h e i r of the same s p e c i e s  characteristics and Leggett  may 1981).  location of reproduction.  t h a t spawn i n the same stream  morphological, between  In most  cases,  stocks stocks  For example, a l l f i s h e s  or a l l f i s h e s  o f the same  8  species  that  discrete  spawn  stocks.  Oncorhynchus considered coastal interior  keta,  as one  to  et  stock. coho coho.  Great  particular  in  streams  of  the  Taylor  and  McPhail  stocks  Oncorhynchus  in  many  reviews  Larkin  of  systems  ( B i e t t e et  (1981) and  Stock  definition  Information 1)  traits  that  development; The well  2)  as  analyses  stocks.  on  in  relation  effective  first  because  they  that  are  to  falls  Electrophoretic  glance,  the  not  a n a l y s i s has  l a r g e samples can  be  in  the  fisheries  Fraser  (Merritt  and  River  Roberson  has not  and been  fisheries  management  of  identification.  the  handled  and first  DNA.  The  stock  i n t o two  unaffected  a f f e c t e d by  mitochondrial  are  used  In g e n e r a l , phenotypic  methods  presumed to be  physiological,  At  from  discrete  see  (1981).  known or  of  be  were  timing of reproduction  to d e f i n e w i l d s t o c k s  traits  should  that  including  former i n c l u d e s k a r y o t y p i c , e l e c t r o p h o r e t i c and  morphological,  use  are  concept  relies  collected  River  salmon,  as t h a t a s s o c i a t e d with the l o c a t i o n of spawning.  stock  Loftus  chum  as  (1985) proposed  been  a l . 1981).  considered  all  Fraser  ( B u k l i s 1982), Copper River  Lakes  the  has  be  that  kisutch,  timing  g e n e t i c v a r i a t i o n a s s o c i a t e d with s e a s o n a l  For  proposed  may  (1985)  Migratory  i n v e s t i g a t e d as t h o r o u g h l y  area  al.  salmon,  segregate  the  a  Similarly,  1955), Yukon River  1986), and  of  reproducing  spawning  management  streams  Beacham  spawning  (Killick  in  by  includes  variation  by  the  effects  categories:  environment  immunological  methods seem t o be  confounded  the  developmental  latter  behavioural  broad  of  environment. analyses  as  analyses  of  among  proposed  the  most s e n s i b l e  of  the  to  environment.  been the most popular  f o r f i s h e r i e s work because  rapidly.  itself  This  lends  w e l l to  "In  Season"  9  management o p e r a t i o n s .  However, i t i s o f t e n d i f f i c u l t  to  o f e l e c t r o p h o r e t i c v a r i a t i o n t o the e c o l o g i c a l v a r i a b i l i t y may  be  stock  more  important  specific  conservation due  to  of  physiological can  also  a pattern  polymorphic  concordance  its and  be  maintenance  in  drift.  and  future  adaptations  genetic  variation  for  of  behavioural  used  to  between  morphology,  Relatively  underlying  variability  management  information  needed  For  both  the  question  is:  Does a p a r t i c u l a r  occurred? an  (i.e. a  f i s h e r i e s manager and  migration  the  observable  timing  has  the  key  occurred phenotypic  morphological, of a  Clearly,  define  than  species  there  "stocks"  is  and  the  evolutionary  biologist  d i s c o n t i n u i t y i n the indicate  that  the  first  ecology  of a  evolution  has  E v o l u t i o n i s d e f i n e d as g e n e t i c change as a r e s u l t o f a d a p t a t i o n  ecological  situation  (Hartl  1981).  always compare two  The  words  populations  "to  Secondarily,  wishes to t a k e .  change"  i n one  what  information  to is  occurred?  T h i s depends upon the approach one comparative.  a  processes.  difference)  r e q u i r e d to determine i f e v o l u t i o n has  be  to  the  behaviour  that of  in  decisions.  i n f o r m a t i o n needed to understand e v o l u t i o n a r y  species  studies  It  to p r e s e r v e  or  variation  intensive  genetic  production  physiology  enzyme  pattern  i n the s p e c i e s .  c h a r a c t e r i s t i c s o f proposed s t o c k s  make  the  and  r e l a t e the  way  implies  this.  or another  Studies In  must  effect,  ( E n d l e r 1986).  always we  must  10  E v o l u t i o n can proceed  1)  A  population  i n two ways:  can change  response t o a change  genetically  and, perhaps,  i n t h e environment.  phenotypically i n  This i s the s e r i a l  progression  approach ( F i g u r e 1 ) .  One  compares what  to be.  Great  2)  population  Examples o f p r o g r e s s i o n s  sapiens, change  a single  horses  o f wing Britain  Ephippus e t c .  i s now as opposed t o what i t used  a r e found  (Stanley  c o l o r a t i o n i n moths  i n the f o s s i l  1979) and i n extant  (Biston  spp) with  approach s i n c e one compares two p o p u l a t i o n s  a common  because  populations i . e .  industrialization in  They can change  and o f t e n p h e n o t y p i c a l l y t o occupy d i f f e r e n t n i c h e s .  have  i . e . Homo  ( K e t t l e w e l l 1956).  P o p u l a t i o n s can branch away from each o t h e r .  evolution  record:  derivation.  i t i s the p r o c e s s  understanding  This  latter  by which  o f t h i s process  k i n d s o f organisms  (Hutchison  I have chosen t h i s  approach.  genetically  T h i s i s thebranching t h a t a r e assumed t o  mode o f e v o l u t i o n i s i n t e r e s t i n g  speciation  ultimately  occurs.  An  a l l o w s one t o e x p l a i n why t h e r e a r e so many 1959).  Since I am i n t e r e s t e d i n s p e c i a t i o n  11  I  SERIAL  F i g u r e 1.  BRANCHING  S e r i a l and b r a n c h i n g e v o l u t i o n  12  So defined  again  ... What  above,  information  has occurred?  i s required  I f an  t o determine i f e v o l u t i o n , as  ecological  situation  does  result  in  s p l i t t i n g , one might p r e d i c t the f o l l o w i n g :  1)  Phenotypic d i f f e r e n c e s among the p o p u l a t i o n s .  2)  An  adaptive  basis  to  phenotypic  variation  between  the  groups  would be conducive t o g e n e t i c  change  (selectivity differences). 3)  The d i f f e r e n c e s i n phenotype have a g e n e t i c b a s i s .  4)  Aspects o f the s p e c i e s (i.e.  "homing" t o p l a c e  ecology  of birth,  small  s t r o n g s e l e c t i o n at p o i n t s i n the l i f e  Restated  as q u e s t i o n s  effective  population  sizes,  history).  t o be answered:  1)  Are t h e r e phenotypic  2)  Do these  3)  Are the d i f f e r e n c e s i n phenotype  d i f f e r e n c e s among the p o p u l a t i o n s ?  f e a t u r e s have an a d a p t i v e  basis? g e n e t i c a l l y determined?  Are the  stocks g e n e t i c a l l y d i f f e r e n t ? 4)  How d i d t h e s t o c k s become g e n e t i c a l l y d i s t i n c t ? factors i n genetic  differentiation?  5)  Are t h e r e a l t e r n a t i v e e x p l a n a t i o n s  The  purpose o f t h i s work i s t o determine i f p o p u l a t i o n s  different show  What were the c a s u a l  seasons: 1) a r e t e m p o r a l l y  characteristic  phenotypic  f o r the o b s e r v a t i o n s ?  t h a t spawn d u r i n g  i s o l a t e d even when i n the same l o c a l e ;  differences  i n the adults  or  f r y ; 3)  2)  show  13  evidence  of  adaptations  environments; the  first  the  factors  4)  are  that  and  illustrated  affect  life  stages  of  in t h i s  life.  The  empirical but  o f spawning, and phenotypic  suggested  the  the  population  these  of  the  by  next two  to  season  on  chum  survival  time  vertebral  Three  main  during  The  populations  different  of  relative  incubation of  sections confirm reproduction  adults  counts  and  and  spatially  the  the  program  time  to  to  emerge and  the  incubation  section to  the  describe  the  overlap space.  i n time Evidence  vertebral  time to hatch,  season  timing  features is  of  of  suggested  of the  as  a  populations.  reproduction  incubation  rate,  the  at m a t u r i t y ,  the g e n e t i c b a s i s of s t o c k in  of  next  to  early  groups i s  selection  the  has  i n the  u n i f o r m i t y o f phenotype among the rate  species  separated  morphological  Stabilizing  are  returning  seasons  length  points  explanations  salmonids.  salmon  adult,  form a major component  reviews  in  In  describe  the  s t r u c t u r e of t h i s  at m a t u r i t y ,  populations.  comparisons  of  during  through measures o f the s e a s o n a l  comparisons o f age  migration,  The  cycle.  briefly  races'  spawn  isolation  life  abundance  to  hence s e l e c t i o n i s g r e a t e s t  'seasonal  information  p o s s i b l e cause o f the Adaptation  of  section  to  and  seasonal  stocks.  chum salmon ecology  the r a t e o f s t r a y i n g o f spawners i n time and  freshwater  of  on  s t r u c t u r i n g among s e a s o n a l l y and  i n v e s t i g a t e d by  progeny  of  respective  component; 2) m i g r a t i o n s  next  reported  degree o f temporal  downstream  seasonal  their  genetically distinct  distribution  s e c t i o n : 1)  origins  same l o c a l e  counts,  and/or  c y c l e ; 3) m o r t a l i t y and  evolutionary presents  the  in  literature  j u v e n i l e phases  both a geographic and of the  survival  phenotypically  s e c t i o n I review the  embryonic,  for  for  is  environments.  specific  vertebral  adaptations number  and  14  e x t e r n a l morphology o f the f r y based on the r e s u l t s o f l a b o r a t o r y r e a r i n g s o f the progeny o f the s t o c k s under c o n t r o l l e d c o n d i t i o n s .  These among  the  different than in  two  populations  are followed using  by  section  sections.  provide  enzymes.  interesting  contrast  management. to  those  divergence  i s an  It i s also a standard  differences for fisheries an  This  o f g e n e t i c r e l a t i o n s h i p s among  a n a l y s i s using .quantitative t r a i t s . stock  an a n a l y s i s o f g e n e t i c  polymorphic  approach t o the q u e s t i o n  determining  this  sections  populations  p r a c t i s e used  The r e s u l t s o f of  the  previous  Some c o n c l u s i o n s drawn from the i n f o r m a t i o n c o n t r a d i c t those  from q u a n t i t a t i v e t r a i t s and t h e r e f o r e f o r c e a change i n p e r s p e c t i v e the r e l a t i o n s h i p s among t h e p o p u l a t i o n s . important  entirely  In the f i n a l  presented.  regarding  s e c t i o n I summarize the  c o n c l u s i o n s o f t h i s work and s y n t h e s i z e t o p r o v i d e  apparent c o n t r a d i c t o r y i n f o r m a t i o n  drawn  r e s o l u t i o n t o the  15  SELECTION AND  THE  ECOLOGY OF CHUM SALMON  Chum salmon, Oncorhynchus of  ket a,  f i s h o f the North P a c i f i c Ocean.  the  Pacific  salmons  the  anadromous  species  spp.)  (Figure  i n the n o r t h  Pacific  2)  (Bakkala  Ocean  1970).  considerably  The  exceeds  other salmon s p e c i e s (Bakkala 1970).  Chum result  salmon  the l i f e  downstream  undergo history  migrant;  several  transformations  coastal  juvenile;  These may  reproductive  concerned mainly  stages  adult)  (coastal  Between  these  migrant) t h a t  juvenile, are  pelagic  be grouped i n t o  pelagic  important  involve  with  transition  Rim.  salmon  their  juvenile;  freshwater s t a g e s  concerned  stages  in  freshwater  As  coastal  a  mainly  (coastal  adult;  (egg t o f r y ,  biology,  and  marine  with  adult;  anadromous and catadromous m i g r a t i o n s .  spawn  life.  i n t o s t a g e s : egg t o f r y ;  reproductive  juvenile)  a s s o c i a t e d causes o f m o r t a l i t y and m o r t a l i t y  Chum  during  i s most c o n v e n i e n t l y d i v i d e d  reproductive adult.  the  variable  It has the widest endemic d i s t r i b u t i o n o f  (Oncorhynchus  s t a n d i n g crop o f chum salmon  i s a highly  growth.  downstream  Each stage  has  rates.  streams  throughout the  North  Pacific  In North America the southernmost r e c o r d o f occurrence o f chum salmon i s San  Lorenzo R i v e r  i n Monterey,  ( A t k i n s o n et a l . 1967).  Spawning  far  as the Mackenzie R i v e r  the  Northwest T e r r i t o r i e s  (long.  California  streams e x i s t 135°W.,  (long.  122°W.,  from t h i s  lat.°37  point  northward as  l a t . 69°N.) on the A r t i e  (Aro and Shepard 1967).  30°N.)  coast  In A s i a the s o u t h e r n  of  limit  F i g u r e 2.  World d i s t r i b u t i o n  o f chum salmon.  17  is  i n the Saga P r e f e c t u r e  Sea o f Japan River  (Kimura  ( l o n g . 130°E., l a t . 33°N.) o f Kyushu I s l a n d ,  1981)  while  spawning  occurs  as  f a r north  as  i n the  the  ( l o n g . 125°E., l a t . 73°N) on the A r t i e coast o f the U.S.S.R. (Sano  Lena 1966)  (See F i g u r e 2 ) .  In A s i a t h e r e are two reproduction: the  Amur  forms o f chum salmon r e c o g n i z e d by t h e i r season o f  the summer chum salmon n a t i v e to Kamchatka, the Okhotsk  River  and  the  east  coast  salmon n a t i v e to Japan, S a k h a l i n Amur R i v e r (Sano 1966). August.  peak  Island,  Island  the southern  the  Soviet  districts  of  o f Kamchatka mature a d u l t s runs  in July  August  or August  Sakhalin Japan,  through  and  the  Kurile peak  to  Olyutorskii,  Kurile  early  Islands  spawning  forms or  autumn  chum  I s l a n d s and the  west  ascend t o spawn from June to September  with  1966).  October  spawning  runs  "races"  t h e r e i s evidence t h a t they e x i s t  onward.  the  (Sano  Anadyr,  (Sano occurs  occur  are  July  1966). in  accepted  (Bakkala 1970).  and  there  are  two  and August and another In  the  September  i n September  less  Okhotsk  In the Amur R i v e r  I s l a n d and October and November on Honshu and Kyushu  Seasonal  the  Summer chum salmon migrate t o spawn i n June, J u l y and  s e p a r a t e spawning runs o f chum salmon, one d u r i n g from  and  The autumn chum salmon spawn mostly from September  In coast  of Sakhalin  coast,  and  rivers  and  October  of  the  October.  In  on  Hokkaido  i n North America  although  Islands.  A g e n e r a l t r e n d o f spawning  l a t e r i n the year with d e c r e a s i n g l a t i t u d e o c c u r s throughout the range.  18 There are two Alaska in  temporally d i s t i n c t  ( B u k l i s and Barton  early  May  spawning  run  occurs  range  from  periods  September  and  1984).  continue in  and  i n southeastern  and  until  July.  August  Alaska  Spawning Columbia. as  are  over  takes  880  place  chum  from  In  (Salo  salmon  October  compared  to  November  to  January  and  Harrison  Columbia spawning  runs  occur  middle  the  of  spawning to  in  In  i n the  the  Further  south,  autumn spawning  to August on  in  Prince  British  the  the  south  of  the  northern  year.  of  Columbia. of  British  i n October i n the C h e h a l i s mainstem  and  October.  streams in  The  state  rivers  January  the  July.  Alaskan  i n September and  Rivers.  earlier  of  rest  1986).  For example, peak spawning o c c u r s  Chilliwack-Veddar  and  the  in northern  Wales I s l a n d , chum salmon spawn mainly  There  i n the Yukon R i v e r ,  summer chum salmon enter the Yukon R i v e r  spawning  June  July  The  spawning m i g r a t i o n s  Fraser  part  September on the Queen C h a r l o t t e I s l a n d s and d u r i n g J u l y and  River,  of  Spawning o c c u r s  River  British  i n August  August on  the  n o r t h e r n B r i t i s h Columbia mainland (Aro and Shepard 1967).  In Washington spawning o c c u r s mainly al. et  1967)  although  a l . (1967) note  December i n Oregon.  i n December and  t h e r e are spawning runs that  spawning  occurs  i n October mainly  in  January  (Koski late  ( A t k i n s o n et  1975).  November  Atkinson and  early  19  LIFE HISTORY IN FRESHWATER  A d u l t Phase  Coastal Adult  Like a l l P a c i f i c  salmon, chum salmon  r e t u r n to t h e i r  stream  of b i r t h  to  spawn and then d i e .  Once Parker  mature  chum  (1962) e s t i m a t e d  0.035 at t h i s Taguchi the  the  stage.  the A  salmon  begins  mean monthly  total  a  migration  instantaneous  m o r t a l i t y of  freshwater.  m o r t a l i t y r a t e to  0.070 o c c u r r e d  over  two  100  days  of  ocean  existence  of  the  chum  (1976) regards t h i s estimate as'much too h i g h .  salmon.  be  months.  (1961) g i v e s a mean monthly i n s t a n t a n e o u s m o r t a l i t y r a t e of 0.381  last  harbor  towards  However,  for  Ricker  S p a l d i n g (1964) r e p o r t e d t h a t  s e a l s and sea l i o n s are the main p r e d a t o r s d u r i n g the r e t u r n j o u r n e y .  Spawning A d u l t  Chum streams  salmon  (Bakkala  t i d a l zone. stream.  g e n e r a l l y spawn 1970).  In  Migrating fish  However,  some  these  (Sano 1966,  upstream.  The  than  populations  Neave 1966).  i n c r e a s e d water  200  situations  are n o t a b l y  grounds up t o 2500 km upstream River  less  km  flow  the  sea  some spawning may  reluctant  undertake  in  i n the  t o surmount b a r r i e r s  i n the  long  migrations  as the  to  spawning  Yukon and  the Amur  l a t e r spawning p o p u l a t i o n s migrate at t h i s  time  smaller  occur  i n l a r g e r i v e r s such The  from  may  b a r r i e r s t h a t impede the p r o g r e s s of e a r l i e r a r r i v i n g  allow fish.  them t o  further surmount  20  Sex for  ratios  have been  shown t o change  d u r i n g the spawning m i g r a t i o n but  the e n t i r e p e r i o d o f m i g r a t i o n they approach  1:1.  The  number o f males to  females d e c l i n e s d u r i n g the course o f the spawning run ( S a l o  Age  composition  changes  as  the  spawning  season  e a r l i e r migrants are o l d e r than l a t e m i g r a n t s . that  the mean age  2.98  i n October  Mattson  and  o f spawning chum salmon  t o 2.78  Roland  i n December  (1963) found  age 4 f i s h dominated  Although  years  that  age  dominated  survival.  The longer a male chum salmon can remain  is  important  p o t e n t i a l mates he can encounter.  lower p r o b a b i l i t y greatly  to  mating  success  a  few  Greater longevity  days to s e v e r a l months  contrast,  migrants  and  year.  their  and  from  relative  egg  to  fry  a c t i v e the g r e a t e r number  o f redd s u p e r i m p o s i t i o n by another  from  In  early  a l l spawners d i e once r e p r o d u c t i o n i s completed  in  varies  1970's.  l a t e migrants at T r a i t o r s Cove, A l a s k a i n one  freshwater  Generally,  Fraser River declined  d u r i n g the  longevity  of  progresses.  For example, S a l o (1986) noted  i n the  3 fish  1986).  i n the female means a  female.  Freshwater  (Trasky et a l . 1974,  life Koski  1975),  Spawners are s u b j e c t to a v a r i e t y o f p r e d a t o r s w h i l e they are attempting to  migrate  and  spawn.  Bears,  gulls  and  bald  eagles  take  advantage  presence o f the f i s h i n a r e l a t i v e l y c o n f i n e d a r e a d u r i n g t h i s phase.  of  the  21  Egg t o F r y Phase  Both a b i o t i c and b i o t i c characteristics temperature, spawners,  stock  Drought indirectly 1953).  gravel  may  1975).  The  influence  Parker  mean monthly  cause  egg  Stream  (1962)  the  flow,  water  time, d e n s i t y  well-being  estimated that  instantaneous rate  allowing  mortality  other  when stream d i s c h a r g e was be the r e s u l t  directly  mortality  McNeil (1966) and Wickett  years may  1975).  c o m p o s i t i o n , spawning  characteristics (Koski  (Koski  of  of  the  92.2  per  of mortality  during  0.364.  may by  fry  i n Hook Nose Creek p e r i s h e d d u r i n g the seven months o f the  t o f r y phase.  t h i s p e r i o d was  emerging  oxygen,  chum salmon  cent o f chum salmon egg  the  dissolved  and  embryonic  of  f a c t o r s i n f l u e n c e the s u r v i v a l o f embryos and the  (1958)  by  leaving  causing  factors  found low oxygen  low d u r i n g and a f t e r spawning. of a greater  the  incidence of  to  redds  dry  operate  and h i g h  (Neave  mortality  Poor s u r v i v a l  freezing  or  o f redds  i n dry (McNeil  1966).  The affected increases flows  duration by and  the  (Bams 1982).  stocks  may  incubation  velocity  larger  water v e l o c i t i e s early  o f the  of  water  period at  f r y are produced Summer chum salmon  the  and nest  at h i g h e r  migrate  progeny o f s t o c k s t h a t spawn l a t e .  size  site. stream  o f the  f r y may  Developmental flows than  spawn i n deeper waters and  than do the autumn chum salmon therefore  the  earlier  and  (Salo at  1986). a  larger  at  be rate  lower  at h i g h e r  The progeny size  than  of the  22  Water temperatures for  significant  According Chum  or at f r e e z i n g d u r i n g the i n c u b a t i o n can account  mortalities  t o Schroder  salmon  near  eggs  of  salmonid  (1973) a drop  incubated  eggs  i n water  below  1.5°C  and  alevins  temperature during  stocks often s e l e c t During  areas with  inhibits  early  s i g n i f i c a n t l y h i g h e r m o r t a l i t i e s than c o n t r o l s (Schroder u p w e l l i n g groundwater  (McNeil  1966).  spawning.  development  1974).  had  Late spawning  t h a t remains above 4°C.  severe w i n t e r s the autumn chum salmon have g r e a t e r egg t o f r y s u r v i v a l  than summer chum salmon ( N i k o l s k i i  Late  spawning  stocks  may  1952).  also  require  fewer  temperature  units  to  emergence than e a r l y spawning s t o c k s (Koski 1975).  S u r v i v a l o f chum salmon eggs and a l e v i n s i s d i r e c t l y r e l a t e d t o d i s s o l v e d oxygen content be  1.67  levels  (Wickett  mg/liter.  1954).  Koski  below 2 m g / l i t e r .  (Alderdice development  et  (1975) found Lethal levels  a l . 1958, F a s t  can  cause  a  Wickett  (1954) c a l c u l a t e d that rise  and Stober  reduction  survival from  1984).  i n the  the l e t h a l  was  reduced  fertilization Low  incubation  oxygen rate  l e v e l to at oxygen  to hatching during  of  early  the embryo  ( A l d e r d i c e e t a l . 1958).  S u r v i v a l r a t e s can vary g r e a t l y depending on the composition in  the g r a v e l .  composition 88.4  F o r example,  o f the g r a v e l ,  Koski  found  by s y s t e m a t i c a l l y a l t e r i n g the  that s u r v i v a l s  per cent depending on t h e mix.  are d e p o s i t e d on the streambed,  (1975),  of materials  ranged  from  7.2 per cent t o  When f i n e m a t e r i a l s such as sand and s i l t  p e r m e a b i l i t y i s reduced.  Gravel  composition  23  a f f e c t s the s u r v i v a l o f salmonid a l e v i n s i n t h r e e ways: 1) d i r e c t of  eggs and a l e v i n s ;  2) reduced  intragravel  water  flow  suffocation  and d i s s o l v e d  oxygen  c o n t e n t ; and 3) a p h y s i c a l b a r r i e r t o emergence (Iwamoto e t a l . 1978).  The  morphology  survival.  Chum  and behaviour  salmon  embryos  alevins  Pacific  salmon  (Fast  through  smaller i n t e r s t i t i a l  o f chum salmon a l e v i n s are r e l a t i v e l y  and Stober spaces.  slender  1984).  Potentially,  alevins  i s thought safely  exhibit  photonegative  behaviour  p r e d a t o r avoidance  (Fast  them  this  c o u l d make them  to move  to c o n f i r m t h i s .  shortly  after  hatching.  by keeping  their  to o t h e r  allows  t o be an a d a p t a t i o n f o r p r e d a t o r avoidance  i n the gravel u n t i l  compared  This  v u l n e r a b l e t o p r e d a t o r s although no i n f o r m a t i o n e x i s t s salmon  can i n f l u e n c e  less Chum This  the a l e v i n s  they a t t a i n the morphology necessary f o r e f f e c t i v e  1985).  MARINE LIFE HISTORY  Downstream Migrant Phase  After  completing  their  embryonic  development  the f r y emerge  g r a v e l and migrate downstream to the s e a i n the s p r i n g . generally Ishikawa  o c c u r s d u r i n g one t o two hours 1964, Godin  1982).  following  from the  Downstream m i g r a t i o n  nightfall  (Kobayashi and  24  In c o a s t a l streams the m i g r a t i o n night also  (Hoar 1958).  However, i n some systems  (Mason 1974).  may  require  fry w i l l  requires only  migrate  during  the  M i g r a t i o n o f F r a s e r R i v e r chum salmon f r y o c c u r r e d  d a y l i g h t hours (Todd 1966). fry  of f r y to the e s t u a r y  two  to  In longer  three  months  rivers, to  their  downstream  day  during  such as the Amur or the  complete  one  Yukon,  migration  (Smirnov 1975).  Downstream migrants may r e q u i r e s more than recorded  after  one  feed  night  sunset  i n freshwater  (Smirnov  r a t h e r than  1975).  However, peak  Rosly  foods  (Kostarev  1970;  the f r y was  due  Godin  (1982) suggested of entry  with l a t i t u d e  (Godin  combining  growth  rate  Frolenko  1970;  Kobayashi  (1972) s p e c u l a t e d  and  of  1982).  timing young  into  of  that  for  each  seawater.  The  Walters annual  chum salmon  population annual  production and  the  of  m i g r a t i n g d u r i n g the peak o f the  there  effect  zooplankton, of s i z e  mortality  greater  important  Ishikawa  1964).  flow  was  years.  an  date  optimal increases  et a l . (1978) u s i n g a computer s i m u l a t i o n  the  suffer  1960).  g r e a t e r i n years where  mean e n t r y  that  would  been  t h a t the b e t t e r c o n d i t i o n of  f o r the F r a s e r R i v e r chum salmon concluded peak  f e e d i n g has  to improved f e e d i n g o p p o r t u n i t i e s d u r i n g the low  annual t i m i n g  model  Rosly  migration  P l e c o p t e r a l a r v a e are  (1972) demonstrated t h a t the c o n d i t i o n o f f r y was  t h e r e were lower f l o w s .  i f the  d u r i n g the d a y l i g h t hours (Kobayashi  Chironomidae, T r i c h o p t e r a , Emphemeroptera, and freshwater  particularly  relative run.  ration  selective  fry migrating compared  predation  before to  level,  or  those  after fry  25  Coastal  Juvenile  B a i l e y e t a l . (1975) found t h a t zooplankton  i n the e s t u a r y  the chum salmon j u v e n i l e s  of T r a i t o r s  Cove,  Alaska.  They  s u r v i v a l o f f r y depends on t h e i r growth r a t e and t h e i r a b i l i t y predators.  The concluded t h a t  in m o r t a l i t i e s . months.  Parker  The mean  competative  instantaneous  noted  t h a t the  t o escape  i n t e r a c t i o n s f o r food  (1962) e s t i m a t e d m o r t a l i t y  monthly  fed h e a v i l y on  could  from  result  at 94.6 per cent over  rate  of mortality  over  the  was 0.582  five  during  t h i s phase.  Pelagic  Juvenile  Chum several  salmon  years.  will  Asian  remain  dispersed  North  Pacific  Ocean f o r  chum salmon extend eastward as f a r as 140°W compared t o  a westward l i m i t o f 175°E f o r North American chum salmon.  Little  i s known  o f the causes  (1962) e s t i m a t e d m o r t a l i t y instantaneous salinity 1958;  mortality  during  Birman  (Polistotrema  (Lamna d i t r o p i s ) , harbor  seal  rate  of  0.017.  residence  Predators  stoutii),  during  t h i s stage.  lamprey  Low  water  temperatures  may a f f e c t s u r v i v a l a d v e r s e l y  of pelagic (Entosphenus  juveniles  vitulina),  f i n whale  include  tridentatus),  f u r s e a l ( C a l l o r h i n u s u r s i n u s ) , sea l i o n  (Phoca  Parker  at 43.4 per cent over 34 months with a mean monthly  e a r l y ocean  1959).  of mortality  (Balaenoptera  and  (Wickett  the  hagfish  mackerel  (Eumetopis physalus),  low  shark  jubata), humpback  26  whale  (Megaptera  (Delphinapterus  nodosa),  leucas)  killer  whale  (Clemens and Wilby  (Orcinus  in  incubation  coastal  i n the egg to f r y and c o a s t a l  These  are determined  by  the spawning  s i t e as w e l l as the annual t i m i n g o f spawning.  marine  juvenile  may  also  D i f f e r e n c e s i n development r a t e w i l l i n t o the e s t u a r y  beluga  S u r v i v a l i n the egg t o f r y phase depends on the c o n d i t i o n s  environment.  c h o i c e o f redd  and  1946).  Most o f the m o r t a l i t y i n chum salmon occurs j u v e n i l e phases.  orca)  depend  on  the  adult's  S u r v i v a l o f the  incubation  environment.  a f f e c t the t i m i n g o f the m i g r a t i o n o f f r y  (See F i g u r e 3 ) .  Subspecific levels of organization  Several appear  levels  to e x i s t  of genetic  i n chum salmon.  differences  i n the l e n g t h ,  categories,  fecundity.  The  sexes  maturity. final than  year  The sexes,  weight,  show d i f f e r e n c e s i n l e n g t h  at sea and hence o f the same  females  return  age  return (Salo  below  the l e v e l  populations  age at m a t u r i t y  and  'races' e x h i b i t two  at age and age at  more r a p i d growth r a t e i n t h e i r  t o spawn at a g r e a t e r 1986, Bakkala  1970).  t o spawn at age 0.2 while  r e t u r n t o spawn at age 0.4 ( T h o r s t e i n s o n  o f the s p e c i e s  and, i n the l a t t e r  at age, weight  Male chum salmon have a r e l a t i v e l y  females  males than  organization  et a l . 1963).  length  and weight  In g e n e r a l ,  more females than  more males  E  Fry Emergence size date time of day number  TEMPERATURE ol INCUBATION Eggs sizes hatch dates numbers  £  Coastal Juvenile  Downstream migrant  Egg to Fry  NERITIC ZONE  GENOTYPIC VALUES spawning date egg size development rate* Fry- -Subadult growth maturation threshold  Spawners ages sizes dates fecundities '^W sexes  Pelagic Juvenile  . . . . . . . . . . . .  — PELAGIC ZONE remain al sea  \  ages sizes dates sexes numbers  Return Migration timing .4 duration  Coastal Adult return to s p a  Size maturation threshold  w n  Final Sea Year growth survival  Reproductive Adult Figure 3 . A model of chum salmon l i f e h i s t o r y genotype (C) and environment ( E ) .  showing the i n t e r a c t i o n between s e l e c t i o n  (S),  28  Among chum salmon p o p u l a t i o n s t h e r e are d i f f e r e n c e s i n the average l e n g t h of  spawners,  morphology.  weight  at  According  age,  age  populations  a  rivers  along  absolute  Beacham  those  size  differences compared  (Sano 1966).  latitudinal  fecundity  than  The  absolute  gradients.  than  southern  i n body depth  to  chum  Svetovidova  salmon  (1961) found  in d i f f e r e n t  populations  More  southerly  o f chum salmon  from the  the  Amgun  River  had  Bira the  populations 1966).  higher  (1956)  and  external morphological and  (Sano  populations Birman  from  and  f e c u n d i t y at  found  significant  Issuri  Amur  Such  a  distribution  example,  Okazaki  group  Rivers  River  seasonal  geographic  races.  migration,,  as  estuary.  d i f f e r e n c e s i n trunk  body depth between p o p u l a t i o n s  more or  may  be  less  f u n c t i o n as  characterized  as  or r e t u r n to spawn at a p a r t i c u l a r  (1981) on  the  of several 'regional populations'. a broad  had  However,  basis  of  an  a  length, spawning  genetically  having  a  time  area.  These of  differ  spawning,  in size  example  location at  of of  year.  e l e c t r o p h o r e t i c a n a l y s i s of  These c o n s i s t e d o f a number of  Another  certain  time o f the  polymorphic enzymes c h a r a c t e r i z e d North American chum salmon as being  in  spawning  f e c u n d i t y a l s o d i f f e r s among  populations.  a number o f s t o c k s may  unit.  geographic  external  t r i b u t a r i e s o f the Amur R i v e r .  Finally, cohesive  and  In Japan spawners from  northerly populations  head l e n g t h , diameter o f the eye,  For  to the south.  (1982) demonstrated t h a t n o r t h e r n  given  fecundity  r i v e r s are l a r g e r and h e a v i e r than those o f the same age  i n the n o r t h e r n  higher  maturity,  to Sano (1966) spawners i n more n o r t h e r n l y  tend to mature at o l d e r ages than the southern  at  this  i s the  spawning,  maturity,  composed  populations  phenomenon  time  morphological  of  of  spawning features,  29  d i s t a n c e migrated  from the s e a , average weight o f spawners,  and a b s o l u t e f e c u n d i t y . and  September  coast spawns  usually  locations  September  chum  In the Amur  less  external  chum  including  salmon  than  100  morphological  km  Kamchatka,  the Amur  River,  River  from  salmon  than 2.5 kg f o r summer  o f summer bodies,  chum  on average than the  t h e summer  t h e sea (Sano  t o autumn chum salmon.  salmon  S a k h a l i n , and  Autumn chum  the autumn chum  deeper  August  the n o r t h e r n  The autumn chum  500 t o 1000 more eggs  features  had r e l a t i v e l y  deeper heads compared  as  area.  to less  1000-2000 km from t h e sea whereas  tributaries  compared  River  3.5 kg as compared  salmon.  such  t o the end o f November.  Autumn chum salmon c a r r y  tributaries  Summer  above  locations  Sea and the Amur  Japan d u r i n g weigh  salmon.  to  northern  i n more s o u t h e r l y  northern  summer  In A s i a , the summer chum salmon spawns d u r i n g  i n more  o f the Okhotsk  age at m a t u r i t y ,  salmon  migrates to  chum salmon m i g r a t e  1966).  Grigo  and autumn chum shorter  pectoral  (1953) salmon.  f i n s and  30  THE  DISTRIBUTION AND  ABUNDANCE OF SEASONAL RACES ANC  SPECULATIONS REGARDING  THEIR EVOLUTIONARY ORIGIN  REVIEW  I  shall  present  a  selective  methods o f c l a s s i f i c a t i o n and  must be  review  to  also  races.  review  The  separated  hypotheses  habitat s h i f t insect  o r i g i n of s e a s o n a l  The  ichthyologist an analogy, races.  more fecund,  shortly  t h e i r heimal almost  ecotypes  chum salmon  proposed by as  White  a  in p a r t i c u l a r . of  I  seasonal  (1978) f o r s e a s o n a l l y  convincing  groupings  in fishes  seasonal  t o Berg  Berg.  the  theory  was  diffuse  made  Berg  (1934),  races i n t o two  groups:  (1934) i n d i v i d u a l s  in  for  the  literature  on  and  a d a p t a t i o n and  closer  o f the heimal  to  the  by  the  race  are  classification  o f two  mouth o f  o f season of a r r i v a l ,  opposing  "heimal" larger,  up to a year p r i o r to fecund, the  spawned  river  Subsequent o b s e r v a t i o n s i n d i c a t e t h a t f i s h  l e n g t h o f s t a y i n freshwater  Soviet  g r a i n s as  " v e r n a l " and  v e r n a l race were s m a l l e r , l e s s  e n t e r i n g freshwater counterparts.  1934  using cereal  spawn f u r t h e r upstream and e n t e r freshwater  A rigid  historical  are a widespread  evolutionary origin  coalescing  every c o n c e i v a b l e combination  fecundity 1959).  at  I n d i v i d u a l s o f the  after  the  presented  geographer, L.S.  classified  According  spawning.  attempt  seasonal and  is  and  although  races.  earliest  intra-specific  regarding  hypothesis  populations  that  r e v i s e d , seasonal  common f e a t u r e among anadromous f i s h e s  shall  show  than  exhibit  season o f spawning,  b e f o r e spawning ( R i c k e r  phenotypes as proposed by  Berg  31  (1934) i s not  adequate to encompass the v a r i e t y seen i n n a t u r e .  recommends t h a t  no  attempt  be  made to  f i s h e s i n t o the v e r n a l or heimal  Historically, been c a l l e d  within  a  isolated am  species  interested  isolation  to  variability temporal is  hence  in  a  genetic  classification spawning  from  an  groupings  genetic  of  grouping.  divergence fall  called  different  times  but  do  populations  separated  seasonal  sibling in  I  (many  a  fishes  local  populations)  reproductively In t h i s  localized  groups  times  among  ecology  not  area  categories:  that  during  migrate  during reproduction  at  a)  represent  whether  also  Thus,  different different  it  isolation  that  seasons times  ( e . g . chum salmon).  method  separates  seasonally  populations  and  distinct  migrate  (e.g. and  the  reflects  This c l a s s i f i c a t i o n because  I  satisfactory  consider  populations  study  whether such  most  for reproduction  populations.  spawn  to  perspective  to the p o t e n t i a l  two  is  the  have  i t . Firstly, it  species.  believe  time o f r e p r o d u c t i o n .  among  into  anadromous  of  However, such  groupings  migration  according  groups  temporally  groupings  l a r g e grouping  change.  evolutionary  migrating  b)  such  seasonal  s e p a r a t i o n at the  salmon);  of  i s o l a t e d p o p u l a t i o n s or demes w i t h i n a s p e c i e s and  in  useful  seasonal  whether  results  approach  another  migratory  problems a s s o c i a t e d with  of one  might as w e l l be  in  reproductively  isolation  from  groupings  seasonal  T h i s term has  implies reproductive  stocks  (1959)  category.  intraspecific  'races'.  f o r c e a l l known  Ricker  at  chinook  are  also  32  Many s p e c i e s o f f i s h of  migration.  For example,  salmon,  Chinook  Other  spawning  i s not  two  late spring  species  distinct  (1972)  are  time  brown  trout  char  sturgeon minnow  (Salvelinus  (Acipenser (Rutilus  alpinus),  Aral  (Salmo  summer  differs  sturgeon  barbel  (Huso  (Acipenser (Barbus  salmon  charr  (Frost  (Lampetra  1966),  ayresi),  (Diptychus  dybowskii),  (Rutilus  rutilus),  redbelly  dace,  encompasses show  that  Bream  sturgeon  Atlantic  (Chrosomus  brama),  (Lucioperca  herring eos)  time  brachycephalus),  salmon  carp  (Tyler  1981),  Shemaia  1959).  This  been  (Smirnov 1975), pink (Brannon 1949)  (Cyprinus  harenqus)  1966).  salmon  seasons have  (Neave  lucioperca)  (Clupea  1984),  Windermere lamprey  carpio),  osman  1959),  volba  (Berg  (Norman list  by  1975), no  phenomenon  exists  in  widely  divergent  Petromyzontidae, C l u p e i d a e , Salmonidae, C y p r i n i d a e and  taxa  Percidae.  such  and  means  a l l s p e c i e s t h a t have s e a s o n a l l y a l l o c h r o n i c p o p u l a t i o n s but this  of  cut-tooth  (Acipenser g u l d e n s t a d i i ) , r i v e r  (Abramis  sander  but  fall  ruthenus),  ( P e l e c u s c u l t r a n u s ) (Berg  et a l . 1985), A t l a n t i c  stellate  and  Atlantic  (Oncorhynchus gorbuscha) (Ivankov 1967), sockeye salmon (Burger  distinct  sharpnose  f o r a wide v a r i e t y o f f i s h e s such as chum salmon  chinook salmon  River  huso),  P o p u l a t i o n s w i t h i n s p e c i e s t h a t spawn d u r i n g d i f f e r e n t recorded  Columbia  chinooks;  trutta),  timing  (Oncorhynchus nerka) ( A l t u k o v  beluga  (Chalcalbumus c h a l c o i d e s ) and chekon  i n the  of migration  nudiventris), sterlet  frisi i),  in t h e i r  are four t e m p o r a l l y  chinooks;  where  (Salmo s a l a r ) (Berg 1934), sockeye salmon Artie  notes t h a t  tshawytscha, t h e r e  chinooks;  fish  or more forms t h a t d i f f e r  Packer  Oncorhynchus  stocks: early spring chinooks.  have  as  does the  33  Seasonally Chum  salmon  spawns  seasonally (Berg  in  distinct  1959,  British  isolated  streams  spawning  Smirnov  Columbia  populations  1975,  (Neave  may  around  occur throughout the s p e c i e s the  populations  Altukov  1966),  north in  1981),  and  Pacific  Japan  Alaska  i n Puget  Rim.  (Ricker  (Buklis  range.  There  1972),  are  U.S.S.R.  and  Barton  1984),  Sound, Washington  (Koski  1975).  There are no r e p o r t s o f s e a s o n a l demes i n Oregon.  Berg  (1934)  noted  that  there  were two  t y p e s o f chum salmon,  autumn, i n S i b e r i a n and Kamchatkan r i v e r s . designated mainly  infraspecies  during  infraspecies November.  fJ. k e t a  mid-July  f l . keta  A similar  to  keta,  autumnalis,  spawned  during  early  Koski  (1975) many o f the r i v e r s o f n o r t h e r n B r i t i s h stocks  spawn from September of chum salmon, Washington  that  Buklis  spawn i n J u l y  and  January.  Barton  and August  'early'  and  (Koski 1975).  'late',  The e a r l y  (1934) Rivers  autumn  September  1984).  form,  to  early  Columbia and  spawn  the  According  to  southeastern  but the m a j o r i t y  t o November (Neave 1966, A t k i n s o n et a l . 1967).  of stocks Two  runs  i n the streams w i t h i n Puget Sound,  run, as t y p i f i e d by K o s k i ' s d a t a from B i g  Beef Creek, Washington, spawned from the f i r s t o f October.  the  and  i s observed among s t o c k s u t i l i z i n g  River  have  1982;  whereas  Yukon  Alaska  (Buklis  i n the Amur and Anadyr  September  timing difference  i n Alaska  The summer form, which Berg  spawned  early  summer  week o f September  to the middle  The l a t e run spawned from mid t o l a t e October t o the b e g i n n i n g o f The  difference  in  spawning  time  among  p o p u l a t i o n s appears to be around seven t o e i g h t  allochronic  weeks which  chum  i s comparable  the recorded d i f f e r e n c e s among e a r l y and l a t e s t o c k s i n the Vancouver southern B r i t i s h  Columbia mainland area and  i n Hokkaido  salmon to  Island -  ( R i c k e r 1972).  Early  34  and  late  runs  i n the  high  latitude  are, i n months, a s s o c i a t e d with spawn  in  illusion  autumn  and  because  latitudes  are  'summer  comparable  the m i d - l a t i t u d e s  of  the  months.  to  i n the  summer and  and  (Appendix  Explanations focussed  winter  stocks  autumn  Yukon R.  and  autumn whereas the  I  believe  this  stream  winter  month' stream  ignored  Although Berg  genetics  (1934) b e l i e v e d  by  considering  return  v i c e versa,  seasonal  races  to  environmental  the  end  hypotheses demes.  from  the  o f the  have been proposed  Schmidt  from  periodically the many  by  last  the  lengthening  i c e age.  sea.  regarding  (1947) h y p o t h e s i z e d  successive  developed t h e i r anadromy and distance  i s caused  authors be  a  They assume t h a t factors  rather  evolutionary  origin  divergence.  Several  resulted  timing  migration  subsequent  the  of seasonal  in  demes i n f i s h e s have  or f e e d i n g .  than g e n e t i c  high  i t u n l i k e l y t h a t a summer chum  autumn chum salmon and  i n migration  in  an  temperatures  consequence o f the e n e r g e t i c s o f a d u l t m i g r a t i o n variation  be  17).  o f the e v o l u t i o n a r y o r i g i n s o f s e a s o n a l  salmon c o u l d produce an  stocks  to  temperatures  on e c o l o g i c a l or p h y s i o l o g i c a l f a c t o r s a f f e c t i n g the  adults.  U.S.S.R.  southern  difference  month'  'autumn to  the  According  and to  the  that s e a s o n a l shortening  Schmidt  of  demes i n f i s h e s river  courses  (1947) f i s h e s  originally  r e p r o d u c t i v e s t r a t e g y of homing i n r i v e r s a s h o r t  With  the  growth  of  the  glaciers  these  rivers  i n c o r p o r a t e d i n t o much longer systems such as the Paleo-Yukon  Paleo-Amur. species:  Schmidt (a)  some  (1947) proposed fish  at  retained  that  their  two  site  s t r a t e g i e s evolved fidelity  and  were and  within  migrated  the  35  length  o f the l o n g e r  gravel  beds;  rivers.  (b) some  Each  reproduction. could  not  To o f f s e t  group  fish  spawned  developed  Thus, Schmidt  complete  impassible  Paleozoic river  they  the  evolved  systems  t o spawn  i n the lower  adaptations  in their  reaches  o f the  mode o f  (1947) argues t h a t s i n c e the upper r i v e r  spawners  to enter  in  one  season  freshwater  with  lengthened  their  journey  i n accordance  traditional  before  up t o a year  the  river  prior  became  t o spawning.  the e n e r g e t i c c o s t s o f the journey and the i n c r e a s e d r i s k s o f a d u l t  freshwater m o r t a l i t y , these f i s h became l a r g e r and more fecund than the f i s h e s spawning i n the lower  reaches.  As the g l a c i e r s receded and the r i v e r s  the two groups came t o spawn more c l o s e l y season  of  reproduction  and  together.  characteristic  Each group  spawner  size  shrank,  retained i t s  and  fecundity.  A t l a n t i c salmon p o p u l a t i o n s i n the S o v i e t Union have p r o v i d e d a good model f o r t h i s h y p o t h e s i s (Berg 1959).  Unfortunately, phenotypic  requirements  of l a t e season season  fish  o f the e a r l y  of this  chum  salmon  seasonal  model.  spawners  races  do  In P a c i f i c  i n the r i v e r  not  always  f i t the  salmon t h e r e i s no r e c o r d  until  the next  g e n e r a l l y are l a r g e r  spawning s t o c k i n a system  (Koski  year  and more  1975, Berg  t o spawn.  fecund  Ivankov  (1967) notes t h a t  Iturup I s l a n d t h e summer pink salmon spawns upstream  salmon. spawning (Birman  A  reversal  stocks  also  of  the m i g r a t i o n  occurs  1981) and the chinook  pattern  i n the sockeye salmon  (Healey  among  salmon 1983).  than  1934, R i c k e r  K r o g i u s e t a l . 1934, Kubo 1950) but o f t e n they spawn i n t h e same  r a t h e r than f a r t h e r upstream. and  with  spawners remaining  Late  1972,  fishes  locale  i n the S a k h a l i n R i v e r from  the autumn pink  seasonally  separated  o f the Kamchatka I t appears  that  River  Schmidt  36  (1947) was into  determined  Berg's  Abakumov and  regressions  changes  proposed  i s similar sea  i t differs  d e s c r i b e d by  restricting  that  withdrawals o f the  o f the  i n sea  By  explanation  of  the  origin  himself  he  of  seasonal  failed  to  races  explain  the  in nature.  (1961)  This h y p o t h e s i s  However,  f i t an  (1934) model.  d i v e r s i t y observed  intrusions  to  level.  that The  Schmidt.  at  the  end  shortening the  and  rivers  process  method s i n c e a g r a d u a l  the  fish.  Schmidt's  change  repeated  glacial  period.  have  been  or  more  t h a t two  i n t r u s i o n s and  of r i v e r  lengthening  for  all  its  shortened  groups c o u l d  by  "tracked"  by  suggests  a  ideas proposed  Grotnes  (1980)  rapid  i n other  As w e l l , c u r r e n t models such as the "Punctuated E q u i l i b r i u m " model o f Gould 1982)  of  form  (1985).  1979,  those  that  o f .salmonid  (Stanley  as  than  by  studies  evolution  such  drainages.  gradual  faults,  T h i s i s c o n s i s t a n t with  evolution  last  from  i n spawning grounds c o u l d be  hypothesis,  occurred.  o f the  lengthened  were  would  resulted  (1947) s i n c e the  I t h i n k i t l e s s probable  this  s e l e c t i v e event had  sea  demes  to t h a t o f Schmidt  l e d the  in  seasonal  propose t h a t s p l i t t i n g  and  Quinn  of species  occurs  over r e l a t i v e l y s h o r t p e r i o d s of t i m e .  Birman salmon  (1981) r e l a t e d the  in Asia  to  the  conditions  migrations.  the Sea  o f Japan, t h a t are p r o t e c t e d that  temperatures on  the the  summer  of  oceanic  proposed  The  formation  spawning  of  their  seasonal marine  form u t i l i z e s  ocean  demes  period  i n pink of  feeding  difference  occurred  and  grounds,  from c o l d ocean c u r r e n t s .  timing  life  and  chum their  such  as  Birman (1981) because  ocean  f e e d i n g grounds exceeded the optimum f o r e f f e c i e n t  growth  37  thereby  f o r c i n g the summer form to migrate e a r l i e r .  area allow the other  stock to remain at sea l o n g e r .  epochs ocean temperatures experienced today and  are  problems  to e x p l a i n  America.  why  with  there  the  there  Secondly,  are no since  reproduction  this  sea.  are  seasonal  the  I  summer  think  it  and  races  1966). that  In t h i s  spawn  case  that  same c o n d i t i o n s  the  environmental merely  differences  (1981)  and two in  agree  there  i n s p r i n g and  under  to  chum  Birman  salmon  hypothesis  i n the  North  of Japan i n the ocean (1981) a c t u a l l y s t a t e s  keta some  are  isolated  degree  of  so t h a t the  hypothesis  by  season  adaptation  to  f i s h could stay  assumes  the  two  of the  longer  groups  are  i s the case o f the Windermere c h a r r , S a l v e l i n u s w i l l u g h b i i  number o f g i l l  appear  of  (1981)  runs of chum salmon i n the Yukon R i v e r .  autumn  likely  Birman's  growth and  were  than  identical.  F i n a l l y , there  charr  Birman's  Canadian chum salmon.  seasonally d i s t i n c t  Finally,  genetically  (Frost  earlier  forms were more s i m i l a r  hypothesis.  temperature i n the Sea o f Japan would occur at  two  There i s no thermal d i s c o n t i n u i t y l i k e the Sea  range o f the U.S.A. and that  by  Presumably d u r i n g  this  t h e r e were no d i f f e r e n c e s i n spawning time.  There fails  Temperatures o u t s i d e  not  genetic  forms  of  the  developmental as  he  lists  two  seasonally  autumn t h a t  rakers and  are  differ  ( F r o s t 1966). determined  control. same  animal  and  Windermere  populations  pattern  of  of  scale  (1966) reared both forms  season  concluded,  environment. the  in their  Frost  that  She  isolated  of  spawning  therefore,  differences  However,  Bush  charr  a  as  was  under  that  these  occurred (1975)  case  of  due  does  to not  sympatric  38  speciation.  More  autumn c h a r r the  could  evolved  were i n t r o d u c e d possibility  occurred  Child  separated to other  by  also,  but  the  did  lake  Frost  rule  out  although  still  as  a  divergence result  other  charr  which spawned  latest  s e l e c t i o n pressures, other  towards  those  charr  spring  which  stocks.  survival and  one  spawned  a  of h e r r i n g .  possibilities, She  of  supposed  those  another  charr  geographic  He  or more  both  advantage  i n the season and  deep-water  favored  in  for  proposed  populations  which  at any  time o f depth.  spawned the  suppose  early  survival The  two  and  mean  the  "Then in  of  the  those  s e t s of  shallow-water spawning  would  time  of  breeding  i n deep water.  spawning,  intermediately  that  which  working towards autumn and  and  of  as  have  i d e a o f geographic s e p a r a t i o n  from l a t e autumn to e a r l y s p r i n g and  water  then  could  the  continuous  i n shallow  and  two  that  c h a r r was  season  the  scenario  of  favored  that  (1966) proposed t h i s  divergence  advantage  comparing  from each other  sympatric  some  By  and  isolation.  two  the  spring  (1980) concluded  from s p r i n g to autumn i n one  d u r i n g a p e r i o d o f geographic  advanced  Windermere  frequencies.  autumn spawning p o p u l a t i o n s  that spawning season s h i f t e d  (1966)  gene  Child  (1958) advanced a s i m i l a r  o r i g i n o f s p r i n g and  that  seasons i n i s o l a t i o n  not  basin  found  esterase  populations  t h e i r breeding  Blaxter  Frost  (1980)  i n t o Lake Windermere.  within  barrier. the  be  gene f r e q u e n c i e s  forms had  a  recently,  the  s e l e c t i o n against  place."  Thus,  Frost  (1966) proposes s e p a r a t i o n by d i s r u p t i v e s e l e c t i o n .  The  other  near 8 j h.  hypothesis  i s that  spawning  i s t r i g g e r r e d when  daylength  is  F r o s t (1966) s p e c u l a t e s t h a t i f some autumn spawning c h a r r matured  39  l a t e they might miss t h i s supposed spawning cue  and  be  f o r c e d to wait u n t i l  a  s i m i l a r 8^ h d a y l i g h t regime would occur again i n the s p r i n g .  Of  a l l the  hypotheses  put  forward  those  Windermere c h a r r are the most p a l a t a b l e . the o r i g i n one  was  of seasonal  races  (1966) c o n c e r n i n g  However, as F r o s t  i n f i s h e s must be  not t h e r e to r e c o r d the event  divergence was  of Frost  first  the  (1966) p o i n t s out  a matter f o r s p e c u l a t i o n s i n c e  hand.  An a c t u a l event  of seasonal  noted by White (1978) i n monophagous i n s e c t s .  According  to White  (1978) s e a s o n a l  'races' of i n s e c t s have come about  due  to h a b i t a t s h i f t s and subsequent a d a p t a t i o n o f the s e a s o n a l r e p r o d u c t i v e c y c l e to  the  new  habitat.  monophagous i n s e c t , on  apples.  end  The  For  example,  the  species  Rhagoletis  i n f e s t e d o n l y Hawthorn f r u i t s u n t i l  emergence p e r i o d o f the apple  1864  pomonella,  when i t appeared  'race' i s from  June  15  to  the  o f August with an emergence p e r i o d about a month b e f o r e the maturation  apples i n the a r e a . 15 approximately then the apple  The  Hawthorn  'race' arose  the apple and  subsequently  In  the  general,  focussed on  visible  with  ecological  this  assumption generated.  most  5 and  o f the Hawthorn f r u i t s .  of  October  Presumably  from the Hawthorn when some i n s e c t s o v i p o s i t e d on s u r v i v e d to  hypotheses  phenotypic  of  is  variation  important  reproduce.  the  variability  approach  t h a t phenotypic The  'race' emerges between August  a month b e f o r e maturation  a  aspect  that  origin  of  the  among the two one  i s either  cannot  seasonal  races  groups.  The  effectively  g e n e t i c a l l y or  of seasonal  races  i s the  have  problem  test  the  environmentally potential  for  40 genetic  i s o l a t i o n o f p o p u l a t i o n s coupled  incubated drive  i n dramatically different  either  with  thermal  the f a c t t h a t the o f f s p r i n g are  environments.  This  i s l i k e l y to  the phenotypes or genotypes o f each s e a s o n a l l y i s o l a t e d p a i r o f  stocks i n d i f f e r e n t d i r e c t i o n s .  The q u e s t i o n o f g e n e t i c d i v e r g e n c e  salmon s e a s o n a l races has been l a r g e l y  overlooked.  among chum  41  PHENOTYPIC DIFFERENTIATION IN SEASONAL ECOTYPES OF CHUM SALMON (Oncorhynchus keta)  INTRODUCTION  According seasonal  to Birman  races.  This  (1981)  phenomenon  genus i n the chum salmon, 0.  Phenotypic and  temporal  characteristics (Kubo  1956)  stocks  vary  variation axes.  a l l species  of  reaches i t s h i g h e s t  in  development  among chum salmon p o p u l a t i o n s occurs Geographically  embryonic many  Oncorhynchus  have  within  the  keta (Berg 1934).  separated  such as polymorphic enzymes  and  the genus  development  characteristics  stocks  along  vary  spatial in  (Okazaki 1981), v e r t e b r a l  (Smoker such  1982). as  time  development, spawning time, d i s t a n c e o f m i g r a t i o n ,  Temporally of  length,  many number  distinct  arrival,  sexual  weight,  fecundity,  shape, polymorphic enzymes and k a r y o t y p e (Altukov 1981, A l t u k o v and  Salmenkova  1981, Berg 1959, Bakkala 1970, Okazaki 1978,  1970).  Smirnov 1975,  Kulikova  Given the s t r o n g c o r r e l a t i o n s observed between p h e n o t y p i c c h a r a c t e r s and season o f r e p r o d u c t i o n , one might c o n c l u d e t h a t these a r e l i n k e d . p o i n t t o f o l l o w i s t h a t the phenotype has e v o l v e d the  animals spawning  at d i f f e r e n t  t i m e s o f the  in  different  R i c k e r 1959,  1972).  logical  i n response t o the needs o f year.  should r e l a t e t o c o n d i t i o n s i n the spawning environment. 1975, Berg 1934,  The  Thus,  the  phenotype  (Bakkala 1970,  Koski  As w e l l , as a consequence o f development  environments, the phenotype  will  be  altered  i n a way  so  that  42  morphologically d i s t i n c t 1970,  Birman  1981).  races w i l l Thus  a  e x i s t throughout  hypothesis  the l i f e h i s t o r y  exists  which  states  (Bakkala  that  as  a  consequence o f s e p a r a t i o n i n time  o f r e p r o d u c t i o n , the phenotype has evolved  in  "seasonal  different  directions  and  so  ( S a v i a t t o v a 1983, Packer 1972, Bakkala is  difficult  also  been  races"  occupy  different  1970, Altukov  1981).  S i n c e consequence  to d i s c e r n using c o r r e l a t i o n s  stated  i n the r e v e r s e  of variables,  fashion.  Seasonal  time have e v o l v e d due t o changes i n phenotypic other p e r i o d s o f the l i f e h i s t o r y  The  central  associated closely  with  h y p o t h e s i s has  d i f f e r e n c e s i n spawning  c h a r a c t e r s and i n the n i c h e i n  (Birman 1981, White 1978).  testable point a seasonal  this  niches  i s that  shift  the d i f f e r e n c e s i n the environment  i n the ecology  t o d i f f e r e n c e s i n phenotype.  Thus  o f the animal  one can d i s t i n c t l y  are l i n k e d identify  a  summer race from an autumn race by phenotype.  Incubation  temperature  characteristics. experience  can  Populations  quite  different  potentially  reproducing  thermal  form and f u n c t i o n o f a t r a i t ,  for  incubation  Compensatory likely  in  Incubation 1959,  environment  adaptive traits  where  r a t e t o hatch  Taning  will  variance  responses  among  phenotypic  or emergence  during  environments  s t a b i l i z i n g s e l e c t i o n , or the p r e s s u r e of  affect  all  different in  developing  seasons  incubation.  will  However,  i n t h e environment f o r the c o n s e r v a t i o n encourage genotypes t h a t can compensate to  produce  allochronic response (Godin  the  optimum  populations varies  with  phenotype.  will  temperature.  1982), v e r t e b r a l number  1950), and e x t e r n a l morphology (Barlow  be most  (Seymour  1961, Fowler 1970) a r e a l l  43  known  to  be  appropriate  altered  variates  f i s h e s (Godin 1982,  On  as  temperature  a l l have  have  separation.  been  correlated  to  These  traits  individual  R i d d e l l and Leggett  are  fitness  been  confounded  by  other  factors  clearly  d i f f e r . i n body  geographic i s o l a t i o n may  1981).  such  as  size,  Brannon  investigate  and  run  timing  populations suffer  has  size,  fecundity,  spawn 100 m i l e s f u r t h e r  (1981,  resulting  and  geographic  1982)  and M i l l e r  phenotypic  and  and  upstream. in  Thus,  (1983) t o  among  salmonid  l i n k between environment,  not been c l e a r l y  tested.  Authors  such  season o f spawning as Bakkala  (1970),  (1981) and Berg (1934) have used environmental d a t a from one system data  such as Beacham  at  phenotype.  Brannon  differences  age  from a confounding geographic component.  In o t h e r cases the proposed phenotype  egg  be the e x p l a n a t i o n f o r the d i f f e r e n c e s  S i m i l a r l y , data used by  phenotypic  in  For example, not o n l y do the summer and autumn chum salmon o f the  River  Birman  incubation.  Swain and Lindsey 1984,  r e t u r n , but autumn chum salmon a l s o  and  of  the o t h e r hand, the c o r r e l a t i o n s observed between spawning season  phenotype  Amur  by  from  another  (1984,  1987),  to  attempt  to  form  Beacham and Murray  a casual (1986a,  link.  In  and  studies  1986b, 1987a, 1987b)  and Beacham et a l . (1987) with the p o t e n t i a l t o i n v e s t i g a t e the s i t u a t i o n on a fine  scale  data was  without  confounding  due  to geographic  e i t h e r not c o l l e c t e d , c o l l e c t e d  meaningless,  or assumed t o f o l l o w  Further,  i n these  temporal  and  studies  spatial  no  distribution  was  the  environmental  i n such a s u p e r f i c i a l manner as t o be  a pattern  effort  factors,  observed  made to  i n neighboring  investigate  o f the spawners to see  systems.  in detail  the  i f p o p u l a t i o n s were  44  t r u l y temporally geographic Beacham  isolated  (i.e.  were s e p a r a t e  b a r r i e r s between groups t h a t (1987):  "Different  trends  they  p o p u l a t i o n s ) or i f t h e r e were sampled.  i n embryo  and  To quote Murray and alevin  developmental  c h a r a c t e r s among f a m i l i e s w i t h i n a s p e c i e s were assumed t o r e f l e c t to v a r i a b l e n a t u r a l incubation c o n d i t i o n s " .  In g e n e r a l l i t t l e e f f o r t has been  a l l o t t e d t o i n v e s t i g a t i o n s o f s e a s o n a l groupings  t o l i n k , on a f i n e s c a l e , t h e  environments, t i m i n g o f r e p r o d u c t i o n and p h e n o t y p i c  An  important  Washington.  exception  Koski  i s t h e work o f K o s k i  traits.  (1975) a t B i g Beef  (1975) was a b l e t o compare a wide v a r i e t y  t r a i t s o f two t e m p o r a l l y  distinct  adaptations  of  Creek,  phenotypic  " r u n s " o f chum salmon t h a t e n t e r  B i g Beef  Creek each year  (There a r e t h r e e runs i n t o t a l but as one o f these was s m a l l  Koski  i t with  combined  detailed  another  for analytical  i n f o r m a t i o n on t h e spawning e n v i r o n m e n t s , p h e n o t y p i c  o f t h e spawners and f r y .  some key c h a r a c t e r i s t i c s o f t h e o f f s p r i n g . t h e f r y spawned  temperature  units  convergence  in  paradoxical  given  incubation. obvious Koski's  later than  i n t h e season  those  downstream  Koski  presented  characteristics  degree o f convergence among  Most i n t e r e s t i n g was t h e tendency t o emerge a f t e r  fewer  spawned  earlier  i n the year.  migration  timing  ( o f the  the d i f f e r e n c e i n timing (1975) suggested  that  o f spawning  was not p u b l i s h e d  r e c o g n i t i o n that i t deserves.  widely,  accumulated The  slight  offspring)  seemed  and temperature o f  s e l e c t i v e facors could override the  d i s c o n t i n u i t i e s i n t h e environment d u r i n g i n c u b a t i o n . work  He  While some c h a r a c t e r i s t i c s o f t h e spawners d i f f e r r e d  between t h e groups, t h e r e appeared a s u r p r i s i n g  of  purposes).  and, perhaps  Unfortunately,  has not r e c e i v e d t h e  45  One  caveate t o h i s work p r o v i d e d by Koski  i n spawning t i m i n g at B i g Beef Creek may selection  by  an  intense  Puget  Sound  appear i n B i g Beef Creek because the  (1975) i s t h a t the d i f f e r e n c e s  be more a r e s u l t o f recent d i s r u p t i v e fishery.  fishery  Two  or  three  removes the  separate  fish  runs  at the  centre  The purpose o f t h i s s e c t i o n i s t o t e s t the i d e a t h a t phenotype and  season  run.  o f spawning are c o r r e l a t e d and t h a t " s e a s o n a l  Ricker  (1972) i n d i c a t e s t h a t  P a c i f i c Salmon are a w i d e l y accepted for  "seasonal  hypothesis  mainly  phenomenon.  of  In c o n t r a s t , a g e n e t i c b a s i s in  nature.  will  among p o p u l a t i o n s .  In  this  chapter  I compare  the  reproductive  c h a r a c t e r i s t i c s o f s p a t i a l l y and t e m p o r a l l y  occur  f a v o r genotypes which  can compensate f o r the temperature d i f f e r e n c e s e x p e r i e n c e d populations.  I  Divergence w i l l  because s t a b i l i z i n g s e l e c t i o n f o r optimum phenotype w i l l  phenotypic  races  t h a t the r e d u c t i o n o f gene f l o w caused by temporal i s o l a t i o n t o occur  speculative  geographic  the  divergence  is  genetically distinct  niches.  propose  allow genetic  races"  r a c e s " occupy d i f f e r e n t  by the a l l o c h r o n i c environments  isolated  and  populations.  46  MATERIALS AND  Study  METHODS  area  I c o n f i n e d my two  adjacent  i n v e s t i g a t i o n s to t h r e e chum salmon p o p u l a t i o n s spawning i n  creeks  populations  in  on  Vancouver  these  creeks  are  populations  where t h e r e are run  the  principle  general  being  Island.  I  assume  that  representative  of  timing d i f f e r e n c e s .  As  the  chum  other  chum  salmon salmon  w e l l , I propose  that  i n v e s t i g a t e d a p p l i e s to a l l a l l o c h r o n i c ectotherm  populations.  Bush  and  Walker  creeks  are  small  Harbor (B.C.) l e s s than  a km  surrounding  is typical  vegetation  dominant s p e c i e s being Thuja  plicata,  heterophylla,  to  Walker  Alder,  spawners  is  (DF0)  1969  1981  to  according  2.5  to  escapement  Acer  rubra  and 4.0  The  3000  123°W ( F i g u r e 4 ) . coast  forest  macrophyllum,  (Hitchcock  and  records  year  m2.  chum  with  years (1950  1).  of -  Canadian  1980)  Dept.  (Appendix  Hemlock,  Tsuga  1973).  i n run  and  populations  are  of  (1.5 -  was  2.0  end  Fisheries  18).  timing  The  8000 m2  to c a l c u l a t e means and  variability  the  Cedar,  Cronquist  salmon  The  Red  from the mouth o f the stream  detailed  t o year  days (Table  Their  Ladysmith  month s e p a r a t i o n i n the s t a r t , peak and  thirty  were s u f f i c i e n t l y  spawning t i m i n g . or (-)  temperate  distance  and have an approximate two  Oceans,  protected  enter  a v a i l a b l e to Bush Creek spawners i s approximately  Creek  reproduction  49°N and  Maple,  Alnus  a c c e s s i b l e , spawn a l i m i t e d km)  at roughly  that  Douglas F i r , Pseudotsuga m e z i e s i i , Western  Broadleaf  and  t o t a l stream bed  apart  c o a s t a l streams  of and  Records  from  variances  for  between  (+)  4.  Bush and Walker c r e e k s :  the study  area  48  Adult  characteristics  To walked  determine  temporal  the creeks  three  and s p a t i a l  to five  1981-82, 1982-83, and 1983-84. were  observed  Bush"  or  i n Bush  "WB"  (Designated  Creek  hereafter)  "Walker"  or  distribution  days per week from September Two t e m p o r a l l y  (Designated  while  "W").  o f spawners,  a  run  was  populations  or "AB" and "Winter  found  circumstances  t o February i n  spawning  "Autumn Bush"  late  These  distinct  observers  in  allowed  Walker  Creek  comparisons o f  p h e n t i c c h a r a c t e r i s t i c s among the t h r e e p o p u l a t i o n s along s p a t i a l and temporal axes (see Table 2 ) .  Chum Creek.  salmon  Late  arriving  spawners  arriving  earlier  have  spawners  but t h e r e  a spatially tend  t o migrate  can be a  example i n 1983-84 t h e r e was a g r e a t Creek  populations.  population early  spawned  However,  the  large  1981-82 section  f i s h spawned i n the s e c t i o n s below. f r y from the l a t e  progeny o f the e a r l y two  reproductive  population.  populations  comparable  t o the d i s t a n c e  population  (Figure 5 ) .  amount  and  distribution  further  upstream  of spatial  amount o f s p a t i a l  i n the upstream  sample t h e m i g r a t i n g the  in  contiguous  1982-83  late  o f the spawning  than  clusters  25  area  s m a l l c o a s t a l streams (Koski 1975, Smirnov 1975 and S a l o  For  w h i l e the  because I c o u l d  distance  meters,  o f spawners  Chum salmon a r e thought t o d i e a s h o r t time a f t e r  those  spawning  contamination  However, the s p a t i a l  separating  overlap.  the  T h i s was convenient  less  than  o v e r l a p among t h e Bush  p o p u l a t i o n without  was  i n Bush  a  within  from  between distance either  e n t e r i n g freshwater i n 1986).  49  T a b l e 1. Mean d a t e s o f s t a r t , peak and end o f Bush and Walker spawning runs from 1969 t o 1981. START  PEAK  creek  chum  END  BUSH CREEK  OCT 1+/-3.5  OCT 28+/-4.5  NOV 20+/-3.0  WALKER CREEK  NOV 16+/-3.5  DEC 10+/-2.5  JAN 1+/-4.0  T a b l e 2. Comparisons between p o p u l a t i o n s a l o n g s p a t i a l and t e m p o r a l axes. AB=Autumn Bush P o p u l a t i o n ; WB=Winter Bush P o p u l a t i o n ; W=Walker P o p u l a t i o n . SPATIAL SEPARATION YES  NO  YES  AB-W  AB-WB  NO  WB-W  WITHIN  TEMPORAL SEPARATION  DIFFERENCES  50  FREQUENCY 40  -i  12  24  36  48  60  72  84  D I S T A N C E BETWEEN GROUPS ( m )  Figure 5.  Distance between spawning groups of chum salmon i n Bush and Walker Creeks  51  To by  check my assumption t h a t spawning time  the temporal  survival  time  distribution  of adults.  Since a l l r e p r o d u c i n g will  be  followed  abundance. of  then  analysis stock.  The dead were counted  animals d i e the temporal  by  life  a  similar  temporal  o f spawners.  computed  proportion necessary  abundance,  f o r both  o f the dead to provide  was  used  were  equal  and  located,  scaling  t o determine  pattern  dead  The  freshwater  residence  (1959);  used  deposition. Gilbert  America.  The other  years  As  and dead linear  the d u r a t i o n  a  much  live  day  smaller  values  counts.  regression  was  Probit f o r each  and dead count  methods  lines  Three systems  and R i c h  (1927);  and Rich method has been most  T h i s method r e c o r d s record  1970).  salmon: G i l b e r t  The G i l b e r t  age from  age from the time  time  of hatching.  o f egg In t h e  and R i c h method a l a r g e a r a b i c numeral r e p r e s e n t s the t o t a l age o f the  f i s h w h i l e a s u b s c r i p t r e c o r d s the years spent fish  adult  time.  and Koo (1962).  i n North  dead  to percentile  f o r the l i v e  the a p p r o p r i a t e  pitched  represent  counts.  age at m a t u r i t y v a r i e s from 0.1 t o 0.6 (Bakkala  Chugunova  freshwater  f r e q u e n c i e s by sampling  conversion  have been used t o r e c o r d the ages o f P a c i f i c  widely  of  will  The mean d i f f e r e n c e between the transformed  estimates  calculated  p a t t e r n o f l i v e a d u l t abundance  The cumulative  live  I  estimated  and p i t c h e d from the stream.  The phase l a g between the two curves  freshwater  were  of adult  c o u l d be reasonably  has spent  two y e a r s  i n saltwater.  numerals separated  i n freshwater  The European  by a decimal  saltwater annuli, respectively.  system  i n freshwater.  including  T h e r e f o r e , a 52  i n c u b a t i o n time  f o r m a l i z e d by Koo  and t h r e e  (1962) uses two  p o i n t r e c o r d i n g the number o f freshwater and Since each annulus i s a c l o s e l y s e p a r a t e d s e t  52  of  growth  rings  on  number  represents  number  represents  using  during  the number  the slow  o f winters  the number o f w i n t e r s  the G i l b e r t  system.  the s c a l e  and Rich  method  growth  of winter,  i n freshwater  spent  would  be  whereas  i n saltwater. a  1.3  fish  report  have  a  I have  freshwater  freshwater  used  the European  annulus  and  using  populations  ranges  British  Columbia  1943).  Northern  uncertain  induced  from  t o 2.48  so  method throughout.  I  have  i n age a t m a t u r i t y  spawners  (Bakkala  3.23 years  i n Bellingham,  the t r e n d  the European  annulus.  Chum salmon  the  zero  In  never  representing  such t h a t more n o r t h e r l y  1970).  F o r example,  i n the Yukon  River  Washington  (Gilbert  i n age at m a t u r i t y  or a g e n e t i c  response  o f the more  1922, P r i t c h a r d (Sano 1966).  reflects  southerly  average  t o 3.17 years i n  stocks  growth t o t h r e s h o l d s i z e f o r r e p r o d u c t i o n  It  environmentally  i n the more n o r t h e r l y  stocks  t o reduce  age at  to o f f s e t higher m o r t a l i t y .  P a c i f i c salmon undergo a dramatic Secondary  striking  changes i n t h e e x t e r n a l morphology.  of sexual  selective  common  sexual  metamorphosis d u r i n g t h e i r  phase.  a  dropped  s t o c k s grow more s l o w l y than southern  whether  slower  maturity  cline  consist of older  o f spawners  from  fish  age when r e p o r t i n g mean age at m a t u r i t y .  There i s a l a t i t u d i n a l  stocks  second  The S o v i e t s add a + t o the age o f mature salmon t o i n d i c a t e that the  this  is  the  first  Thus, a 52  f i s h has undergone an a d d i t i o n a l summer o f growth beyond the l a s t  age  the  characteristics  processes  selective  within stocks  environment.  The  are most  obviously  reproductive expressed  in  These changes are more a r e s u l t r a t h e r than  a stabilizing  rapid  i n the  flux  effect  morphological  53  f e a t u r e s as the animal  i s being transformed  made comparisons among the s t o c k s  u s i n g a wide range o f m o r p h o l o g i c a l c h a r a c t e r i s t i c s  However,  o r b i t - h y p u r a l length  remains  t r a n s f o r m a t i o n to the r e p r o d u c t i v e morph. fitness  in  Oncorhynchus  Energetically, flows  are  high.  autumn l a r g e r them  to  1972,  size  f i s h may  with  stocks  may  be  by  the  be  Van  den  creek.  the  and  later  low  because a  chum salmon  (Koski  1975,  after  Gross  season  as  with  (1984).  when  i n summer  water  or  early  i t i s more d i f f i c u l t  relationship  a l l p u b l i s h e d r e p o r t s of l e n g t h d i f f e r e n c e s of  even  positively correlated  are  Such  constant  Berghe  in  flows  at a disadvantage  shallow  relatively  S i z e was  adaptive  C o n t r a s t i n g l y , when  navigate  consistent distinct  larger  kisutch  unreliable.  Smirnov  1975,  appears  for  to  be  among s e a s o n a l l y Berg  1934,  Ricker  Kubo 1956).  Lengths  were  measured  on  carcasses  recovered runs.  The  i n the  stream  at  regular  i n t e r v a l s throughout  the d u r a t i o n o f the  at each i n t e r v a l was  p r o p o r t i o n a l t o the abundance of spawners p r e s e n t .  V e r t e b r a l counts a l s o remain c o n s t a n t throughout (1956) found t h a t e a r l y and  To  compare  the  mean  number o f a d u l t s sampled  the animal's  l a t e spawning s t o c k s d i f f e r r e d  and  variance  in  in vertebral  vertebral  number  p o p u l a t i o n s , counts were made from a d u l t c a r c a s s e s r e c o v e r e d counts knife.  from  the a d u l t s , the  f l e s h was  Samples were s t r a t i f i e d  stripped  relative  away from  life.  Kubo count.  among  i n 1982.  the  To make  the backbone with  t o the d u r a t i o n o f the r u n s .  a  Where  54  possible, the  samples of  first,  second and  Comparisons subject  the  t h i r d q u a r t i l e s o f the  of  to n o i s e  a d u l t s were made at  interpopulation  from many other  fishes.  orbit-hypural year-olds means  Thus,  factors.  stratified  l e n g t h o f the  with  that  I  a small  spawning  fish.  For  in  sampling  of  composed  of  years.  different  i n c u b a t i o n regime f o r each year  genetically  identical  Year to year c l i m a t i c  with  respect  count v a r i a t i o n c o u l d occur was  also s t r a t i f i e d  by  Length o f a d u l t s stratified  my  age  P a c i f i c salmon may  scales Alaska.  for To  among age  a  to  fish  are  Lindsey  counts  0.4  year-olds.  that  were born  by  the  and  0.3 This  during  f l u c t u a t i o n s would r e s u l t class.  Even  and  in a  i f cohorts  program,  are  vertebral  Thus, v e r t e b r a l number sampling  of the spawner.  number o f a n n u l i  and  age  on  scales  f i s h e s ( C h i l t o n and  be b i a s e d due  Helle  (1979) found  age  determination  reassure  and  v e r t e b r a l number  groups.  i s r e l a t e d to sex  s i m p l e s t method o f ageing  spawning.  to  p o p u l a t i o n sampling of l e n g t h by  Counting the  counts  larger size within  vertebral  0.1  several different thermal  vertebral  example, a c c o r d i n g  r e t u r n i n g as are  to  run.  c o r r e l a t e d with  my  corresponding  Chum spawners r e t u r n mainly as 0.2  proportion  populations  intervals  variability  (1975), v e r t e b r a l number i s p o s i t i v e l y among  time  i n most f i s h s p e c i e s and  these v a r i a b l e s .  i s the  least  scale  among  myself that  chum  Helle's  time consuming  Beamish 1982).  to r e s o r p t i o n o f the outer  that  so I  spawning  (1979) r e s u l t s  in  s c a l e edges d u r i n g  r e s o r p t i o n d i d not salmon  S c a l e ageing  and  are  preclude in  Olsen  use  of  Creek,  u n i v e r s a l l y true  55  for  spawning  estimations consuming  from to  reproductive 1969).  salmon,  otolith  sample  checked  70%  collections.  but  metabolic  I  are  of  scale  O t o l i t h s are  generally  transformation  believed which  compare v a r i a t i o n s i n sex,  Walker c r e e k s ,  recorded  sex,  on recovered  Progeny  age  scale/otolith  and  age  c a r c a s s e s i n 1981  ages  with  more d i f f i c u l t  occurs  and  be  unaffected  in  salmon  age time  by  the  (Calaprice  84%.  length  and  and  sample  to  Agreement between s c a l e s and o t o l i t h s was  To and  chum  o f spawners e n t e r i n g  Bush  o r b i t - h y p u r a l p l a t e l e n g t h were  1982.  characteristics  To  determine  the  timing  of  the  downstream  migration  of  p l a i n t r a p s were s e t o v e r n i g h t below the spawning areas one week,  from  length  of  estimated samples  February time by  were  to  for  fry  July to  in  1982  travel  and from  r e l e a s i n g marked f r y at the also  o c c a s i o n a l l y taken  to  1983.  Once  the  spawning  head  of the  estimate  fry,  inclined  t o seven times  each  week  area  to  per  in  1983  the  the  trap  was  spawning a r e a .  Diurnal  proportion  daytime  the  of  migrants.  Differences compared the  1982  from and  corresponding of  the  i n the mean and  x-rays 1983  of  v a r i a n c e o f v e r t e b r a l counts o f progeny were  f r y samples  captured  fry migrations.  to the approximate 17th,  cumulative  frequency  In  1982  by  inclined  f r y were  plain  sampled  33rd, 50th, 67th, and  distribution  of  individuals  with  traps at  during  intervals  83rd p e r c e n t i l e s time.  In  1983  56  f r y were sampled at i n t e r v a l s c o r r e s p o n d i n g t o the approximate 25th, 50th and 75th p e r c e n t i l e s o f the c u m u l a t i v e frequency  To compare were sampled 1983.  distribution.  morphology o f the o f f s p r i n g ,  using  inclined  the downstream  plane t r a p s d u r i n g  m i g r a t i n g progeny  February to J u l y  i n 1982  and  T o t a l l e n g t h , standard l e n g t h , head l e n g t h , eye d i a m e t e r , snout l e n g t h ,  pectoral  f i n length,  (to  nearest  the  0.1  body g),  depth, head depth and  the  number  ( t o the n e a r e s t  of  parr  marks  0.1  were  mm),  weight  measured  for  comparison o f morphology.  Incubation  rate  Average p o p u l a t i o n knows:  (a) when  development.  incubation  the  I f one  r a t e may  eggs  are  spawned;  knows  the  temperature  p o s s i b l e t o p r e d i c t the time t o emergence emergence.  Chum  variables.  The  salmon adults  streams (Neave 1953).  are spawn  territory  territories  a f t e r one t o two  may  be roughly  a f t e r completing  when  suitable  after  the  during  and compare  particularly shortly  (b)  i n the f i e l d f r y have  incubation  i f one  completed  then  it is  i t to the a c t u a l time t o for estimation  entering  freshwater  of in  these  coastal  A c c o r d i n g t o Schroder (1981) spawning o c c u r s w i t h i n  hours a f t e r  timing  be e s t i m a t e d  formation.  Chum salmon  i n Bush and Walker Creeks form  days o f freshwater  considered  residence.  as spawning t i m i n g .  The  Thus,  escapement  f r y migrate t o sea  embryonic development so t i m i n g o f downstream  marker f o r the end o f embryonic development.  30  migration  is a  57  Although  chum salmon  f r y g e n e r a l l y migrate  to compare i n c u b a t i o n r a t e would be to take samples of the embryos at s e v e r a l times d u r i n g  development.  Providing  only  was  I  have  should  d i f f e r e n c e s among the  Sampling the  redds  at  a f t e r hatch  was  alevins  to  unsuccessful  avoid  in  WB  a small two  in  the  a l l systems  run and  portion  of  independent  (Mason  compare t h e i r  the  total  measures  embryo  of  stage  population  incubation  to  be  sampling  proved  i n c i d e n t a l l y and  Phenotype  intervals largely  during  to  the  unsuccessful  disturbances  due  dominant The  (Dill  sparcely  1981-82  probably  and  redds  incubation  due  Northcote  situated  i f eggs  costly so was  in  sampled  terms  of  not c o n t i n u e d  be  influenced  were the  to  the  1969).  and  by  coho  or  number  d u r i n g the  many  variable influencing incubation  period.  ability  Sampling  high  chum  of  water  incubation Alderdice  seasons.  The  is  dissolved  pers.  comm.).  comparison  of  next  most  oxygen  which  Therefore  incubation  to  i t was  salmon.  Such  destroyed  factors  i s temperature  important  factor  is a  function  avoid  unnecessary  environments  was  1982-83 season.  environmental  time  of  levels.  embryos  importance o f temperature i s enhanced among p o p u l a t i o n s  different  my  certain  can  rate  i n c u b a t i o n r a t e s , samples o f eggs were c o l l e c t e d  A l s o , a c o n s i d e r a b l e number of coho salmon spawned i n upper reaches and difficult  of  populations.  To compare the pre-hatch several  occur  1974).  Another way  from  not  after  development,  sampled,  does  immediately  completing  o f each p o p u l a t i o n  this  downstream  to  of  but  the  (Murray  1980).  reproducing  during  affecting flow  speed  of  i n streams  (D.  complexity  measurements  I of  limited column  58  temperature,  and  temperature were compared u s i n g spot checks every one t o two days i n 1981.  In  and  1983  recorders. recorder (Helle  temperature  Intragravel  and  1979)  between 20  by  was  41  and 40  cm  temperature  cm  (Neave  into  flow  and  measured  spot check w i t h i n  to  were made u s i n g was  temperature,  was  using  Intragravel  range  Hynes  near  from  measurements  the g r a v e l at known redd s i t e s . by  temperature  continuously  Redd depth may  the wier method d e s c r i b e d  The  continuous  measured  redds.  1966).  dissolved  O2.  flow  1982  intragravel  the  21.5  were  cm  taken  Flow measurements  (1976).  Dissolved  Oxygen  measured by spot checks i n the redds.  A c c o r d i n g to Murray  (1980) the r e l a t i o n s h i p between time t o emergence and  temperature  i s negative exponential rather  incubation  may  differ  greatly  T h e r e f o r e I used Murray's  among  than  temporally  Temperature  separated  of  populations.  (1980) model o f the r e l a t i o n s h i p between temperature  and i n c u b a t i o n r a t e t o s t a n d a r d i z e comparisons  (1 )  hyperbolic.  among the p o p u l a t i o n s :  In E - 5.603 - 0.097 T  Where:  E i s the time t o 50 per cent emergence T i s the temperature  ( )  E = e 5  2  Murray single  pair  different  6 0 3  Q  -  0 9 7  T  (1980) developed  the parameter  mating  Creek  o f Weaver  temperatures.  conservative  "  (constant) of incubation  regarding  Murray's the speed  of  estimates using  chum salmon (1980)  reared  model  incubation  at  was low  offspring  i n the chosen  from  laboratory because  temperatures  a at  i t is  compared  59  with o t h e r i n c u b a t i o n models (Jensen, In P r e s s ) . because much o f the embryonic  development  I c o n s i d e r e d t h i s important  o f progeny  from l a t e spawning  adults  w i l l occur at low temperatures.  To demonstrate populations,  the g e n e t i c  d i v e r g e n c e among the e a r l y  and l a t e  spawning  I e s t i m a t e t h e time t o emergence i n each u s i n g t h e model and the  mean temperature  of incubation.  f o r the s e a s o n a l l y  However,  such  an e s t i m a t e does  not account  v a r y i n g temperatures e x p e r i e n c e d by embryos i n n a t u r e .  s t a n d a r d i z e comparisons  so t h a t  both the thermal regime  To  curve and the curved  response o f i n c u b a t i o n r a t e t o temperature were accounted f o r , I s i m u l a t e d the effect  of  temperature  the  incubation  unit  rate  -  accumulations u s i n g  temperature  relationship  6°C as a b a s e l i n e .  thermal u n i t s were summed t o g i v e an a d j u s t e d t o t a l to emergence f o r each p o p u l a t i o n .  (3)  Where:  E6  NTj i s t h e thermal u n i t s accumulated d u r i n g day j .  Ei  i s t h e emergence time at temperature i .  daily  thermal u n i t s  The computations used a r e i l l u s t r a t e d  E10  6  the  The a d j u s t e d d a i l y  accumulated  the i n c u b a t i o n temperature was 10°C:  f o r a day i n which  on  below  60  (4)  NTj  =  X 6  6  NT i  of  e  5.603  -  0.097  X  10  _ e  sum  x  NT,  5.603 - 0.097 X 6  the a d j u s t e d t o t a l thermal u n i t s (T.U.s) to emergence.  M a t e r n a l e f f e c t s r e p r e s e n t a source o f p h e n o t y p i c v a r i a b i l i t y t h a t can be both g e n e t i c maternal  and  environmental i n o r i g i n  effects  include  (Van  V l e c k 1973).  behavioural differences  among  Among  females  s u r v i v a l o f the eggs such as depth o f redd, c h o i c e of redd s i t e and plus  fidelity energy  i n g u a r d i n g eggs a f t e r e g g l a y i n g (Van den Berghe supplied  to  the  embryo  in  the  form  of  p o s i t i v e l y c o r r e l a t e d w i t h i n c u b a t i o n time (Smoker 1982) number (D. Swain, important  factor  salmon.  Thus,  p e r s . comm.).  damp  that and  affect  longevity  and Gross Egg  and perhaps  1984)  size  is  vertebral  Smoker (1982) determined t h a t egg s i z e was  i n the g e n e r a t i o n o f d i v e r s i t y I measured  yolk.  salmonids  dry  females from each p o p u l a t i o n i n 1982  weight and  of  1983.  an  i n q u a n t i t a t i v e t r a i t s o f chum 100  water  hardened  eggs  from  61  Homing and s t r a y i n g  As an index  o f p o t e n t i a l gene flow  among the p o p u l a t i o n s  amount o f s t r a y i n g among the t h r e e p o p u l a t i o n s . were marked u s i n g p e l v i c f r y o f the AB  fall  Fry migrating  Marked a d u l t s were recovered  and winter  of 1984  t o the  f i n c l i p s d u r i n g the s p r i n g of 1982.  p o p u l a t i o n s , 8053 f r y o f the W p o p u l a t i o n and  population.  I estimated  and  the  estuary  I marked 12,432  2111  f r y o f the  WB  from the spawning grounds d u r i n g  the  o f the d i s t r i b u t i o n o f spawners  and  1985.  S t a t i s t i c a l Methods  I was  u n c e r t a i n as  outmigrating  progeny  to the  with  time  normality and  therefore  chose  to  use  measures o f l o c a t i o n to d e s c r i b e the t i m i n g o f the a d u l t and  I used captured  Peterson  by my  be  of  made u s i n g  v a r i a n c e with  the  phenotypic  the  f r y runs.  proportion of fry  traps.  Comparisons generally  mark-recapture method to e s t i m a t e  non-parametric  a Model  interaction  a fixed effect  1 or  (Sokal and  because I was  winter spawning comparison. to minimize the p r o b a b i l i t y R e s u l t s u s i n g t h i s method  characteristics mixed Rohlf  model  among two  1981).  or  three  populations way  I considered  were  a n a l y s i s of population  most i n t e r e s t e d i n the autumn spawning  to  versus  I compared means u s i n g the Tukey-Kramer procedure o f making Type 1 E r r o r with  are c l o s e r t o the  intended  unequal sample  significance  sizes.  level  than  62  those o f other non-orthogonal t e s t s GT2 method are too c o n s e r v a t i v e  Analysis  to t e s t  among p o p u l a t i o n s  (Dunnett  the  GT2  the e q u a l i t y  was performed  beforehand, probability to  Sokal  sizes.  method  this  o f egg weight-female  using  (Hochberg  method  is  BMDP s t a t i s t i c a l  appropriate  Although because  software  program  I  planned  i s preferred  with  1R.  compared  the  i t compensates  I chose t h i s method over the Tukey-Kramer method treatment  regressions  p o s s i b l e comparisons are made.  (1981) the GT2 method  I was comparing a d j u s t e d  length  f o r the l e n g t h c o v a r i a t e , were  1976).  o f Type 1 E r r o r when a l l  and R o h l f  Other methods such as the  (Dunnett 1980).  P o p u l a t i o n mean egg weights, a d j u s t e d using  1980).  tests  f o r the According  unequal  sample  f o r t h i s case because  means and wished t o be as c o n s e r v a t i v e as  possible.  RESULTS  Spawner  The similar the l a s t and  characteristics  temporal  of  spawner  i n 1981 and 1982 ( F i g u r e 6 ) .  abundance  mid-November. or  ended The early  by  mid-November.  median  o f WB  December  with  i n AB,  WB  and W  was  T y p i c a l l y , spawners a r r i v e d i n AB d u r i n g  week i n September, the median o c c u r r e d  spawning  November  distribution  WB  spawner most  i n the t h i r d and  W  abundance  activity  week o f October  spawners peaked  finished  by  arrived  in  at the end o f mid-December.  63  WB  AB  1000-i  1  1981  W  T  875-  0  750625-  0 0 0 0  500375-  1 co  (  oo  o  250CT LU  • WALKER A WINTER BUSH o AUTUMN BUSH  0  125A  A  ID A  AB  1982  4 1000875-  A.  i  TO  i  i  *  r  OCD O  o  750625-  500 375250-  CD 0"" O O  1250 l 255  |  *  A ^  267  00  f^JM  279  291  303  315  327  JULIAN F i g u r e 6.  Timing o f spawning  i n Walker  339  351  363  day.  Number o f l i v e  22  DAY Creek and t h e upper  s e c t i o n o f t h e spawning a r e a i n Bush Creek d u r i n g 1982.  10  spawners  and lower 1981 and  observed v e r s u s t h e J u l i a n  Median day o f each r u n shown by arrow  64  W  spawner  abundance  occurred  in early  t o mid-December  with  spawning  being  completed by l a t e December or e a r l y January.  Variation  i n the median  day o f spawner  p o p u l a t i o n s than among years (Table 3 ) . seven  days  there  was no year  modal  time  difference  occurred  of  i n W.  t o year  spawner  occurring  abundance  between  the 1981  even  1982.  6).  Walker  Creek a d u l t  i n AB was one day w h i l e  Year less  t o year with  and 1982 WB  median o f the WB run was 25-26 days l a t e r and  variation  i n WB.  was  was much g r e a t e r among  The maximum year t o year v a r i a t i o n o f  Year t o year variation  abundance  a  variation maximum  runs.  i n the  two  In c o n t r a s t  days the  than the peak o f the AB run i n 1981  numbers peaked  37-45 days post  AB run ( F i g u r e  The d i f f e r e n c e s among the e a r l y s t o c k (AB) and the l a t e s t o c k s (WB and W)  were even g r e a t e r u s i n g modal  The 95 % c o n f i d e n c e adults  values.  l i m i t s o f s u r v i v a l time i n freshwater  were 0.51 t o 5.95 days  (mean  2.96) i n 1981 and 1982, r e s p e c t i v e l y  f o r Bush Creek  = 3.26) and 1.59 t o 4.33 days (Table 4 ) .  (mean =  The 95 % c o n f i d e n c e l i m i t s o f  s u r v i v a l time f o r Walker Creek a d u l t s were 7.16 t o 8.92 days (mean = 8.04) i n 1981  and 5.35 t o 6.53 days (mean = 5.94) i n 1982 (Table 4 ) .  Temporal o v e r l a p among the e a r l y per  cent  cent  and l a t e s t o c k s was s l i g h t  with over 95  o f the a d u l t s o f the AB run having spawned and d i e d b e f o r e  o f the W and WB  spawners  arrived.  I believe  that  f i v e per  the a c t u a l temporal  s e p a r a t i o n may be g r e a t e r than i t appears because WB pre-spawners m i g r a t i n g t o the upstream a r e a s or post-spawning WB f i s h d r i f t i n g back p r i o r t o death would be observed i n the downstream AB  fish.  area and i n c o r r e c t l y c l a s s i f i e d  as l a t e  spawning  65  T a b l e 3. The y e a r l y median and mode ( i n J u l i a n d a y ) o f t h e t e m p o r a l d i s t r i b u t i o n o f a d u l t s on t h e Bush and Walker c r e e k spawning grounds d u r i n g 1981 and 1982. POPULATIONS METHOD OF ESTIMATION  YEAR  AUTUMN BUSH  MEDIAN  1981  301  1982 MODE  WINTER BUSH '  WALKER  326  338  300  326  345  1981  298  331  344  1982  299  329  345  T a b l e 4. S u r v i v a l t i m e o f (days) a d u l t s i n f r e s h w a t e r a t p e r c e n t i l e s o f t h e d i s t r i b u t i o n o f c o u n t s o f l i v e and dead a d u l t s d u r i n g 1981 and 1982. E s t i m a t e d Freshwater S u r v i v a l Percentile  o f Count  Bush Creek  Time Stream Walker  Creek  1981  1982  1981  1982  5  8.38  0.36  9.65  4.86  15  7.09  1.01  9.25  5.13  25  5.81  1.66  8.92  5.39  35  4.53  2.31  8.46  5.67  45  3.25  2.96  8.07  5.94  55  1.99  3.61  7.67  6.21  65  0.70  4.26  7.28  6.48  l i t h Time  75  -0.59  4.91  6.88  6.75  85  -1.81  5.56  6.19  7.02  66  Three-way was performed  a n a l y s i s of variance  (population,  t o compare v e r t e b r a l count  populations.  Significant  difference  sex, age) with  interaction  d i f f e r e n c e s among the 1982 spawning  (p < 0.05) among  populations  occurred  (F = 10.95, d . f . - 2, P r .05). Comparisons among means (Tukey-Kramer Method) revealed stocks.  significant  differences  spatially  and  WB spawners (5? = 63.0) had fewer v e r t e b r a e  than  (X = 65.1) and the t e m p o r a l l y significant spatial  length  temporal  separation  but  comparisons  spatially  separated separated W  AB (5< - 64.9) spawners (Table 5 ) . No  among  between  temporally  among AB and W a d u l t s where  t o compare a l l p o p u l a t i o n s  differences 1,  separated  d i f f e r e n c e s were observed  plus  sufficient  among  WB  stocks  was  6).  Samples were not  i n c l u d i n g the e f f e c t s  o f sex, age, and  and  i n v e r t e b r a l counts d u e t t o  W  (Table  there  samples  population  revealed  effects  significant  (F = 16.20, d . f . =  113, P = .05).  Two-way population  analysis  by  of  variance  with  sex i n t e r a c t i o n ) r e v e a l e d  r e t u r n among p o p u l a t i o n s = 2.83, Mean  o f WB  differences  i n treatment  or i n t e r a c t i o n  (N = 4 3 1 ) .  during  1982  significantly early  stock,  differences  Comparisons  the  late  younger AB  significant  (population,  sex,  d i f f e r e n c e s i n age at  f o r 1982 (F = 7.00, d . f . = 2, 193, N = 199, P = .05,  Mean o f AB  data  interaction  stocks  spawners  = 2.39, Mean o f W = 2.59).  among  effects  means  combined, (ft -  (ft = 2.83 y e a r s ,  N  were d i s c o v e r e d  59)  significant i n the 1981  (Tukey-Kramer Method) showed WB  and  2.52 seawater =  No  (Tables  W,  were  years,  of  N = 138) than the  7, 9 ) .  i n the age o f r e t u r n o f spawners was found  comprised  that  No  significant  i n comparisons where  t h e r e was a s p a t i a l or s p a t i a l p l u s temporal s e p a r a t i o n among s t o c k s .  67  T a b l e 5. V e r t e b r a l c o u n t s o f 1 9 8 2 spawners : means ( X ) , s t a n d a r d ( S O ) , and sample s i z e s s t r a t i f i e d by p o p u l a t i o n , s e x and a g e .  deviations  POPULATION AB SEX  WB SD  n  X*  W SD  n  X  AGE  X  SD  n  2  65.83  1.169  6  63.38  2.273  24  65.35  1.596  14  3  63.33  1.528  3  61.80  2.761  15  64.50  1.947  23  2  65.42  1.432  6  63.89  3.878  9  65.12  1.759  17  3  65.00  1.410  2  62.85  2.721  8  64.75  1.390  20  65.15  1.518  17  62.96  2.781  56  64.87  1.704  74  FEMALE  MALE  TOTAL  T a b l e 6. S i n g l e degree o f freedom comparisons o f v e r t e b r a l count d i f f e r e n c e s among p o p u l a t i o n s by t h e Tukey-Kramer Method. (MSD ^Minimum S i g n i f i c a n t D i f f e r e n c e ) (* s i g n i f i c a n t d i f f e r e n c e P = .05) D i f f e r e n c e Among Means Di f f e r e n c e Investigated  Comparison  1982  1982  FRY  1983  ADULTS  *  FRY  *  *  Temporal  XWB- X"AB  0.58  (0.372)  -2.19  (1.591)  -2.39  Temporal/ Spatial  X  0.14  (0.379)  0.28  (1.545)  0.63  Spatial  x  (0.384)  -1.91  (0.29)  * A B  -  X  W B  -  x"w  W  *  * 0.72  (0.29)  * (1.018)  -1.76  (0.29)  68  Table 7. Seawater age a t r e t u r n f o r 1981 and .1982 spawners. Means, s t a n d a r d d e v i a t i o n s and sample s i z e s o f p o p u l a t i o n s s t r a t i f i e d by s e x . POPULATION AB  YEAR  SD  WB  SEX  X"  FEMALE  2.88  0.426  130  2.87  MALE  2.79  0.490  135  FEMALE  2.96  0.615  MALE  2.69  1981  TOTAL  1982  TOTAL  n  X"  SD  W  n  X"  SD  n  0.344  23  2.72  0.484  65  2.88  0.353  8  2.78  0.508  70  30  2.36  0.487  44  2.65  0.538  37  0.541  29  2.45  0.510  2.54  0.505  2.84  0.461  265  2.87  0.341  2.76  0.496 .135  2.83  0.592  59  2.39  0.492  2.59  0.521  1981  1982 20 31 64  37  74  69  Three-way a n a l y s i s o f v a r i a n c e length d i f f e r e n c e s r e v e a l e d groups d.f.  i n 1981.  =  1,  treatment  or  significant  [F(pops) = 4.19,  418,  P  =  .05],  interaction  No  (X  significantly - 55.75  stocks  cm,  were  larger  N = 265)  found  i n t e r a c t i o n of  d i f f e r e n c e s among p o p u l a t i o n s  and age  d . f . = 2, 418, P = .05; F(ages) = 19.86,  significant  i n the 1982  (Tukey-Kramer Method) showed that was  ( p o p u l a t i o n , sex, age) with  differences  comparisons.  were  Comparisons  1981 spawners c o m p r i s i n g  (X* = 58.52  cm,  (Tables  9).  8,  i n comparisons with  N  = 31) than No  spatial  found  the l a t e s t o c k ,  significant  to  among means  the e a r l y  or s p a t i a l  due  stock,  differences temporal  WB AB  among  separation  among s t o c k s .  Progeny  characteristics  Sampling the  f r y migrated  re-released night as  both  emerge  migrating  at night  upstream  suggesting  they  streams over a 24 hour p e r i o d  that from  downstream  from  (Figure  7).  the i n c l i n e d  Ninety-eight plain  traps  f r y complete the journey the g r a v e l . were  when  95 per cent  per cent were  recaptured  33 per cent  traps  were  the same  the same n i g h t o f the AB f r y  set  F o u r t y - e i g h t per cent o f the W f r y and 57 per cent o f the WB  of  o f marked f r y  to the e s t u a r y  Approximately  captured  showed over  (Table  f r y were  10).  captured  by the t r a p s (Table 10).  Year-to-year between was  7  population days  variation  i n f r y run  variability.  whereas  the  average  timing  was  The average t i m i n g timing  similar  to  the  average  d i f f e r e n c e between  difference  among  populations  years was  70  T a b l e 8. O r b i t - H y p u r a l P l a t e L e n g t h s o f 1981 and 1982 spawners : means ( X ) , s t a n d a r d d e v i a t i o n s ( S O ) , and sample s i z e s s t r a t i f i e d by p o p u l a t i o n , s e x and age. POPULATION AB  WB  W  YEAR SEX  SD  n  X  20  52.00  1.732  3  53.16  2.873  19  6.276  110  58.75  3.998  20  57.37  2.916  46  52.19  2.851  31  54.00  0.000  1  55.44  3.110  1.8  57.61  4.029  104  61.29  3.729  7  57.81  8.655  52  55.75  5.322  265  58.52  4.456  31  56.68  6.029  135  0.2  54.30  2.042  5  53.52  4.143  28  53.56  3.021  14  0.3  56.03  3.248  25  53.84  5.094  16  54.41  4.497  23  0.2  54.31  2.964  10  53.84  4.132  11  53.16  40.06  17  0.3  55.34  3.249  19  55.31  6.198  9  53.85  5.280  20  55.37  3.100  59  53.90  4.634  64  53.81  4.325  74  X  SD  0.2  51.10  2.639  0.3  55.83  0.2 0.3  n  SD  n  X  AGE  1981 FEMALE  MALE  TOTAL 1982 FEMALE  MALE  TOTAL  71  T a b l e 9. S i n g l e degree o f freedom comparisons among spawning u s i n g t h e Tukey-Kramer Method. Minimum S i g n i f i c a n t D i f f e r e n c e s i g n i f i c a n t d i f f e r e n c e , P = .05) t-statistic Difference  Comparison  1982  Investigated  Equation  Age  Temporal  X" -  X  Temporal/ Spatial  X A B  X  Spatial  X -  X  WB  W B  1981 Length  -0.44  (0.251)  2.77  (2.318)  w  0.24  (0.251)  -0.93  (1.292)  w  -0.20  (0.230)  1.84  (2.432)  A B  populations = MSD. (*  02:00  04:00  06:00  08:00  10:00  12:00  14:00  1&00  18:00  2000  22:00  T I M E O F DAY  F i g u r e 7.  D i e l t i m i n g o f emergence o f f r y from AB, WB and W  24:00  73  Table 10. C a p t u r e e f f i c i e n c y o f i n c l i n e d p l a n e t r a p s below t h e spawning d u r i n g 1983. Population  AB  areas  (1)  WB  W  N.M.  N.R.  T.C.  N.M.  N.R.  T.C.  N.M.  N.R.  T.C.  April 5  25  11  174  0  0  0  50  26  322  A p r i l 12  50  21  201  0  0  0  25  10  67  A p r i l 19  50  15  1507  25  18  99  50  30  373  Apr 1 26  100  36  1588  100  62  797  50  24  236  May 3  100  30  1013  100  51  697  100  53  462  25  3  322  25  11  248  25  2  107  350  116  4805  250  142  1841  300  145  1567  Date  May 14 TOTAL (1)  N.M. = Number Marked N.R. - Number Recovered T.C. = T o t a l Catch  74  9  days.  The temporal  pattern  o f f r y run t i m i n g  compared t o t h a t o f the a d u l t p o p u l a t i o n s were the e a r l i e s t t o m i g r a t e .  was  reversed  among  stocks  such t h a t the l a t e s t spawned progeny  The median o f the WB f r y run was 1-2 days  prior  to the AB run i n 1981 and 1982.  The median o f the W f r y run was 5 t o 22 days  prior  years  t o t h e AB run d u r i n g those  Differences greater  i n timing  i n comparisons  among t e m p o r a l l y  Analysis counts the  among  spatially  stocks  (Table  f r y runs among the p o p u l a t i o n s separated 11).  (with  run time  as  (Tukey-Kramer  Method)  revealed  had  more  vertebrae  (X  =  67.0, N  (X = 66.3, 6.3, N = 111) and t e m p o r a l l y ( T a b l e 12). No s i g n i f i c a n t plus s p a t i a l  1983  populations  block  emerging  r  comparisons  significant separated  120) than  separated  run was  effect) of vertebral  significant  d i f f e r e n c e s among Comparisons  differences stocks  i n mean  (Table 6 ) .  spatially  WB  separated  AB (X = 66.4, N = 126)  d i f f e r e n c e s were observed  s e p a r a t i o n among p o p u l a t i o n s  Analysis of variance the  a  were  the W r u n .  (F = 9.94, d . f . = 2, 342, P = .05, N - 358).  v e r t e b r a l count among s p a t i a l l y and t e m p o r a l l y fry  versus  The median o f the WB  i n the 1982 emerging j u v e n i l e s r e v e a l e d  means  stocks  t o the AB run compared t o 4-20 days a f t e r  o f variance  populations  among  o f downstream  separated  o n l y 1-2 days p r i o r  (Figure 8 ) .  W fry  where t h e r e was temporal  (Table 6 ) .  (with time as a b l o c k e f f e c t ) o f v e r t e b r a l counts i n  juveniles  revealed  significant  differences  (F = 197.84, d . f . = 2, 445, P = .05, N = 450).  means (Tukey-Kramer Method) r e v e a l e d s i g n i f i c a n t  among  the  Comparisons among  d i f f e r e n c e s i n mean v e r t e b r a l  75  • WALKER A WINTER BUSH o AUTUMN BUSH  7200 •  1982  6300 • 5400 •  o o o o 0 u  4500 3600 2700  hX O  <  O  A  1800 900 0  cc  1983 1600  L L  O  1400  oo  1200  oo  1000 800  A A  600  i  400 200  • •  A AA  CD  0 36  48  60  72  84  96  JULIAN  F i g u r e 8.  1—r 108  nO  ' v—i—r 120 132  i " i  144  156  168  DAY  Timing o f f r y downstream m i g r a t i o n s from Walker  Creek and t h e  upper  i n Bush  during  and lower s e c t i o n s 1982 and 1983.  o f the spawning Number  area  o f f r y captured  p l a i n t r a p s versus the J u l i a n day  Creek  i n inclined  76  Table 1 1 . The y e a r l y median and mode ( i n J u l i a n day) o f t h e temporal d i s t r i b u t i o n o f f r y e m i g r a t i n g from Bush and Walker c r e e k s d u r i n g 1982 and 1983. ' POPULATIONS METHOD OP CALCULATION  YEAR  MEDIAN  1982  128  126  106  1983  115  114  110  1982  130  122  101  1983  115  116  90  MODE  DOWNSTREAM BUSH  UPSTREAM BUSH  WALKER  Table 12. V e r t e b r a l c o u n t s f o r f r y m i g r a t i n g downstream d u r i n g 1982. Means, s t a n d a r d d e v i a t i o n s and sample s i z e s o f p o p u l a t i o n s s t r a t i f i e d by t i m e . F r y samples were made a t i n t e r v a l s c o r r e s p o n d i n g t o t h e t o approximate 1 7 t h , 3 3 r d , 5 0 t h , 6 7 t h , and 8 3 r d p e r c e n t i l e s o f t h e c u m u l a t i v e f r e q u e n c y d i s t r i b u t i o n o f individuals with time. POPULATION AB TIME (PERCENTILE]i X  SD  WB n  X  SD  W n  X  SD  n  17  66.71  1.517  24  67.56  1.044  25  66.00  0.666  10  33  66.84  1.666  26  67.05  1.463  22  65.45  1.061  8  50  65.85  1.047  26  66.57  0.945  23  66.19  1.387  26  67  65.58  1.176  24  67.19  0.939  26  66.45  1.214  42  83  67.08  2.412  26  66.63  1.245  24  66.57  0.866  25  TOTAL  66.42  1.482  126  67.00  1.177  120  66.28  1.146  111  77  count  among s p a t i a l l y  fewer  vertebrae  N - 150)  and  well,  f r y had  fry  AB  o f the  temporally  variation  W  and  shift  than  AB than  in  environmental The  among  the  spatially  vertebral However,  vertebral  WB  count.  divergence  the  in  Discriminant  when  characters  analysis  successful  comparing were  1983)  counts  = 1.17,  W  WB  f r y had  (X  =  f r y (Table temporally was  not  66.6,  13).  As  separated  as g r e a t  juveniles  a  between  as  not  showed  substantial  consequence  year-to-year  counts the  may  influence  the  direction  of  years the of  that  juveniles  was  suggests  that  expression vertebral  of  count  genotype-environment  trait.  v e r t e b r a l counts  [VAR(adult)  was  = 5.87;  was  significantly  VAR(juvenile,  1982)  B a r t l e t t ' s t e s t , P < 0.01].  o f morphometric measurements from emerging  within  important  the  juveniles  suggests  in discriminating  samples  of  As  counts  populations  fry vertebral  VAR(juvenile,  moderately  and  of vertebral  differences reversal  the  count  The pooled e r r o r v a r i a n c e o f the a d u l t  r 1.53;  separated  N = 150)  i n t e r a c t i o n p l a y s a r o l e i n the e x p r e s s i o n o f the  g r e a t e r than  (Table 6 ) .  spatially  (X = 67.3,  i n mean v e r t e b r a l  counts.  differences  in  AB.  in interpopulation  vertebral  150)  stocks  the magnitude of the d i f f e r e n c e  variation  year-to-year  year-to-year  separated  comparisons.  in  The  =  separated  but  significant  large.  N  more v e r t e b r a e  Year-to-year  variation  temporally  (X* - 64.9,  s t o c k , W,  in the other  and  each  among the year  discriminators  AB,  (Tables between  WB, 15,  years  and 16)  W but  (Table  fry  was  populations different 14).  The  78  T a b l e 13. V e r t e b r a l c o u n t s f o r f r y m i g r a t i n g downstream d u r i n g 1983. Means, s t a n d a r d d e v i a t i o n s and sample s i z e s o f p o p u l a t i o n s s t r a t i f i e d by t i m e . F r y samples were made a t i n t e r v a l s c o r r e s p o n d i n g t o t h e t o approximate 2 5 t h , 50th and 7 5 t h p e r c e n t i l e s o f t h e c u m u l a t i v e f r e q u e n c y d i s t r i b u t i o n o f i n d i v i d u a l s with time. POPULATION AB TIME (PERCENTILE)  SD  X  WB n  X  W  SD  n  X  SD  n  25  67. 50  0.647  50  64.78  1. 298  50  66.540  50  67.64  0.693  50  64.88  1. 350  50  66.66  1.042  50  75  66. 68  1.096  50  64.98  1. 407  50  66.72  0.927  50  TOTAL  67. 27  0.933  150  64.88  1. 346  '150  66.64  1.346  150  0.762  T a b l e 14. V a r i a b l e s e n t e r e d i n t o t h e 1982 and1983 d i s c r i m i n a n t ranked by importance w i t h c l a s s i f i c a t i o n f u n c t i o n s f o r e a c h . Coefficient  Variable Ranking  functions  for Discriminant Function  1  2 1983  1982  Diameter  1  -  9.29  Snout Length  2  4  0.20  Weight  3  -  Parr Marks  4  1  0.71  5.61  0.79  5.42  0.02  5.02  Head Length  5  2  1.12  3.75  1.20  3.94  2.09  3.95  Head Depth  6  5  3.33  1.41  3.27  1.66  3.06  1.44  Total Length  7  7  2.04  -0.71  2.05  •0.85  2.09  -0.72  Body Depth  -  3  2.84  2.66  2.99  Standard Length  - •  6  2.04  2.18  2.01  '  1982  3  82 83 Eye  1983  50  0.63  •0.83  -0.57  -0.55  1983  8.81  9.31 -1.05  1982  1.31  -1.12  -0.58  79  T a b l e 15. C l a s s i f i c a t i o n m a t r i x function. GROUP  PERCENT CORRECT  f o r 1982 f r y samples u s i n g t h e d i s c r i m i n a n t  CASES CLASSIFIED INTO GROUP AB  WB  W  AB  64.0  96  46  8  WB  58.0  28  87  35  W  81.3  3  25  122  TOTAL  67.8  127  158  165  T a b l e 16. function.  C l a s s i f i c a t i o n matrix  GROUP  PERCENT CORRECT  f o r 1983 f r y samples u s i n g t h e d i s c r i m i n a n t  CASES CLASSIFIED INTO GROUP  AB  WB  W  AB  52.6  80  30  42  WB  55.3  40  84  28  W  61.22  3  36  92  TOTAL  56.4  142  150  162  80  greatest years and  difference  (Tables  AB  i n morphology  17-20).  In 1982, W  f r y (P < 0.05)  (Table  (P  <  0.05).  (P < 0.05). had  WB  W  WB  f r y were  AB  heads  than  WB  significantly  deeper  heads  than  W  longer  heads  W  fry  (P  lighter  fry <  f r y (P  samples were attempted u s i n g  <  0.05).  eyes than  (P  WB  and  0.05).  0.05). In  AB  WB  (Table  f r y had  When c l a s s i f i c a t i o n  W fry  fry  W  and W f r y (P < 0.05). AB  fry  AB f r y had  1983,  f r y (P < 0.05)  1982 d i s c r i m i n a n t  snouts  f r y (P < 0.05).  <  WB  snouts than W  f r y (P < 0.05).  snouts than W f r y (P < 0.05). WB  than  f r y i n both  shorter  shorter  than AB  and AB  s h o r t e r heads than WB  than  smaller  significantly  and AB  and  fewer p a r r marks than WB  f r y had s i g n i f i c a n t l y  shallower  lighter  fewer p a r r marks than WB  deeper  significantly  f r y had  significantly  significantly  significantly  the W and AB  f r y had s i g n i f i c a n t l y  f r y were s i g n i f i c a n t l y  significantly  between  f r y had s i g n i f i c a n t l y  14).  than WB and W f r y (P < 0.05). fry  occurred  had  f r y had 22).  WB  AB  f r y had  significantly o f the  1983  f u n c t i o n the r e s u l t s were poor  (Table 23).  Important  t o note i s the high  misclassi fication  o f the WB  samples.  In  both years w e l l over 40% o f the samples were m i s c l a s s i f i e d .  Incubation  Walker  rates  Creek  incubation period during in  Bush  period  was  0.58°C  (P < 0.001).  the 1982-83 i n c u b a t i o n Creek were compared  warmer  on  than  Bush  Creek  during  than  period  average  (P < 0.001).  0.91°C  warmer  t o the 1981-82 i n c u b a t i o n  i n the  1981-82  Walker Creek was 0.59°C warmer than Bush Creek Water column temperatures  during  period  the  1982-83  (P = 0.021).  temperatures i n Walker Creek were on average 0.90°C warmer d u r i n g incubation  the  1981-82 p e r i o d  (P  = 0.002)  (Figure  9).  incubation  Water  column  the 1982-83 In 1981-82  81  T a b l e 17. f o r 1982.  Approximate t r a n s f o r m a t i o n AB  WB  13.04  W  62.42  T a b l e 18.  comparing group  centroids  WB  29.28  M a h a l a n o b i s d i s t a n c e between p o p u l a t i o n c e n t r o i d s f o r 1982. AB  WB  1.19  W  5.72  WB  2.68  Approximate t r a n s f o r m a t i o n T a b l e 19. among 1983 progeny. AB WB  6.12  W  9.70  T a b l e 20.  F statistic  F statistic  comparing group  centroids  WB  7.32  M a h a l a n o b i s d i s t a n c e between p o p u l a t i o n c e n t r o i d s f o r 1983. AB  WB  0.554  W  0.911  WB  0.688  82  T a b l e 21. Means and s t a n d a r d d e v i a t i o n s o f m o r p h o l o g i c a l c h a r a c t e r i s t i c s o f 1982 f r y s a m p l e s . L e n g t h s a r e i n 0.1mm. Weight i s i n 0.1gm.. (S.M. = Mean s t a n d a r d i z e d t o a common l e n g t h among t h e s a m p l e s ) . POPULATION AB CHARACTERISTIC  MEAN  W  WB S.D.  S.M.  MEAN  S.D.  S.M.  MEAN  S.D.  S.M.  Head Length  80.91 80.55  5.58  80.93 81.14  4.11  81.00 81.08  2.75  Snout  12.20 12.17  0.72  12.79 12.86  1.35  13.83 13.84  1.75  Pectoral F i n Length  39.82 39.77  0.93  40.23 40.29  2.28  40.45 40.52  2.20  Eye  29.73 29.62  1.67  29.27 29.29  1.74  27.69 27.70  1.28  Depth  49.08 48.85  3.26  47.89 48.06  2.63  46.61 46.69  2.33  Body Depth  51.23 50.98  3.53  49.73 49.82  2.53  49.92 50.05  2.64  Length  Diameter  Head  Weight (gms)  P a r r Marks  Trunk  Length  413.97 74.19 406.36 9.35 1.20 9.310 286.26 13.73 284.03  •  367.50 46.52 370.52 9.53 9.54  1.19  282.31 14.08 283.49  341.73 37.53 344.10 8.53 8.54  1.16  282.33 12.96 283.50  14.97 15.47  9.47  12.67 12.79  WT/TL  1.08 1.06  0.16  0.98 0.98  0.09  0.91 0.91  0,.08  KD (Bams 1976)  1.94  0.54  1.91  0.45  1.86  0.43  Caudal F i n Length  4.16  12.40 12.39  4.89  83  T a b l e 22. Means and s t a n d a r d d e v i a t i o n s o f m o r p h o l o g i c a l c h a r a c t e r i s t i c s o f 1983 f r y s a m p l e s . L e n g t h s a r e i n 0.1mm. Weight i n 0.1gm.> (S.M. = Mean s t a n d a r d i z e d t o a common l e n g t h among t h e s a m p l e s ) . POPULATION AB CHARACTERISTIC  MEAN  WB S.D.  MEAN  W S.D.  S.M.  S.M.  MEAN  S.D.  S.M.  Head Length  81.07 81.11  3.07  83.08 82.77  3.58  82.57 82.82  3.54  Snout  Length  14.91 14.92  2.35  15.75 15.62  2.28  14.75 14.78  1.88  Pectoral F i n Length  36.71 36.74  3.77  37.92 37.69  3.79  36.76 37.00  4.07  Eye  Diameter  29.47 29.48  1.22  29.87 29.81  0.85  29.81 29.85  0.93  Depth  44.34 44.35  3.33  45.93 45.74  2.74  45.30 45.40  2.81  Body Depth  48.75 48.79  2.84  48.43 48.27  2.47  49.57 49.65  2.55  Head  Weight (gms)  P a r r Marks  Trunk  Length  364.96 47.69 366.07 9.50 9.50  1.37  236.22 10.51 243.32  369.34 45.60 364.59 9.25 9.21  1.13  236.26 10.53 234.85  8.61 8.60  1.09  233.64 10.42 234.80 54.61 54.81  5.12  53.75 53.79  4.83  53.74 53.42  WT/TL  0.98 0.98  0.101  0.99 0.98  0.095  1.01 1.02  0.091  KD  1.92  0.47  1.92  0.46  1.94  0.43  Caudal F i n Length  4.68  376.07 44.64 380.05  84  Table 23. C l a s s i f i c a t i o n m a t r i x f o r 1983 f r y samples u s i n g t h e d i s c r i m i n a n t f u n c t i o n from the 1982 d a t a . GROUP  PERCENT CORRECT  CASES CLASSIFIED INTO GROUP  AB  WB  W  AB  3.8  6  54  92  WB  19.0  6  30  116  W  66.7  6  44  100  TOTAL  30.0  18  128  308  85  2 300 250 200 150 100 • OCU>  50  i  0  ?^i ^i  n  i ™  O  i  1  1  1  r  T  1982-83  i  1  450 4. 360 270 H 180  *V  90 H ^IT^ttTTpi^jrnry^y-r y — y -  J  1 "1  i  1  T  i—f—i  1 1  15 15 14 • 14 13 12 14 13 13 12 12 AUG SEPT OCT NOV DEC JAN FEB MAR APR MAY JUN JUL 31 30 30 29 29 28 27 29 28 28 27 27 F i a u r e 9.  Temperature and f l o w p r o f i l e s from Bush and Walker Creeks d u r i n g 1981-82 and 1982-83. C l o s e d c i r c l e s = Bush Creek; Open c i r c l e s = Walker Creek.  86  g r a v e l temperatures taken i n the redds were on average 0.132°C warmer than the column  temperatures  in  Bush  Creek  (t  -  3.60,  P  r  .05).  No  significant  d i f f e r e n c e o c c u r r e d between the column and g r a v e l temperatures o f Walker in  1981-82.  The  temporal  variation  in  populations i n which  the  regimes  i n which values.  late  of  spawning  temperature  temperatures before  spring  pattern  (Figure 9 ) .  January  and  Creek  creeks  experienced  out h i g h i n October,  again.  temperatures These  the  results  by  the  WB  and  start  differences  out  are  W  close  t o the  spawning s t o c k s e x p e r i e n c e d i f f e r e n t  marked of  the curve  to minimums i n  experience minimum  important because  a  incubation  then d e c l i n e  embryos  in  embryos  AB embryos e x p e r i e n c e a temperature  start  climbing  regimes  in  temperature  then  climb  to  the embryos o f e a r l y  temperatures  during  particular  developmental s t a g e s .  Progeny did  WB  or  degree-days  W  o f the AB run accumulated progeny  the  A l l populations apparently required  than fewer  t o reach emergence i n 1982-83 than i n 1981-82 (Table 24).  Predicted using  ( T a b l e 24).  more thermal u n i t s b e f o r e emerging  mean  (assuming  no  genetic  temperature  equation  are compared  years AB  actual  t o the  of  variation  incubation  actual  i n c u b a t i o n time was  among s t o c k s ) i n c u b a t i o n  and  incubation  Murray's times  (1980)  i n Table  l o n g e r than the p r e d i c t e d  a c t u a l i n c u b a t i o n times were a l l s h o r t e r than p r e d i c t e d .  24.  times  regression In  w h i l e WB  both and  W  87  T a b l e 24. Comparisons o f accumulated d e g r e e - d a y s (raw and a d j u s t e d d a t a ) and i n c u b a t i o n t i m e s ( a c t u a l and p r e d i c t e d ) f o r AB, WB, and W s t o c k s i n 1981-82 and 1982-83. ( c a l c u l a t e d from median day o f t h e a d u l t and f r y r u n s ) . POPULATION YEAR  AB  WB  1981-82  4.82  3.66  4.36  1982-83  5.68  5.48  6.45  1981-82  192  165  133  1982-83  180  153  130  PREDICTED DAYS 1981-82 TO EMERGENCE  182  204  191  1982-83  168  172  156  MEAN TEMP. OF INCUBATION  TOTAL DAYS TO EMERGENCE  DIFFERENCE (ACTUALPREDICTED)  ACCUMULATED DEGREE-DAYS  ADJUSTED DEGREE-DAYS  W  1981-82  +10  -39  -58  1982-83  +12  -19  -26  1981-82  925.25  603.35  579.65  1982-83  1022.20  839.20  838.25  1981-82  1039  845  873  1982-83  1078  853  834  88  When rates  degree  days  are a d j u s t e d  at d i f f e r e n t temperatures,  the v a r i a t i o n among s t o c k s  t o account  the y e a r - t o - y e a r  remains constant  Comparisons o f samples o f eggs taken period  f o r the v a r i a b l e  incubation  v a r i a t i o n disappears  while  (Table 2 4 ) .  from AB and W i n 1981-82  show t h a t W l a g s behind AB i n i t i a l l y  but g r a d u a l l y  incubation  catches up i n stage  o f development ( F i g u r e 10).  Regression  equations  describing  female o r b i t - h y p u r a l p l a t e l e n g t h  AB  Egg  Egg  P < 0.001)  weight = -0.19542 + 0.00862 X Length  (R-squared = 67.5  W  Egg  are as f o l l o w s :  weight = -0.23808 + 0.00980 X Length  (R-squared = 48.5  WB  the r e l a t i o n s h i p between egg weight and  P < 0.001)  weight = -0.20122 + 0.00926 X Length  (R-squared = 56.4  Analysis of variance  0/  P < 0.001)  o f r e g r e s s i o n c o e f f i c i e n t s over p o p u l a t i o n s  t h a t the l i n e s were not e q u i v a l e n t  revealed  (F = 26.00, d . f . = 4,404, P < 0.00001) (see  89  c c  BUSH WALKER  Figure  2.2  2.0  1.8  LOG  10.  Egg  development  (post-August  31,  stage 1981)  DAY  (Velsen f o r AB  1980)  and W.  versus Horizontal  p r o p o r t i o n a l t o the number o f eggs at each stage  log  day  bars  are  90  Figure  11).  populations P  <  Analysis revealed  0.00001 )  regression slopes  and  lines  of  regressions  and W l i n e s  (P  <  (F  r  of regression  was d i f f e r e n t 62.81,  d.f. =  of  different  (P  =  The  among  0.029).  among  adjusted  (X = 0.26903)  different  <  0.00001 ).  W  egg  weight  versus  and  and  intercepts  of  (P < .001).  length  the  WB  W  (F  revealed  that  25.25,  d.f. r  =  means u s i n g  the GT2  were s i g n i f i c a n t l y  lower  the a d j u s t e d 1,197,  P  method r e v e a l e d than W  AB The  were  and  AB  The s l o p e s o f the  (P = 0.203) but the i n t e r c e p t s were  of covariance WB  P  (F =• 2.61, d . f . = 2,266, P < 0.07568).  regressions  Analysis  of p a i r s of  (F = 22.07, d . f . - 2,286,  2,266,  AB  were e q u i v a l e n t  coefficients  from AB  and  differred  weights  W  WB  0.001).  Comparisons  t h a t WB  were a l s o s i g n i f i c a n t l y  WB  weight  variance  were e q u i v a l e n t  the  significantly  of  different mean egg  < 0.0001). that  WB  (X = 0.29793)  egg  (Table  25).  Homing and s t r a y i n g  The  returns  populations  of  was  marked  substantial  between AB and WB  with  fish  indicate  (Tables  found  %) o f t h e r e t u r n s i n AB r e t u r n e d  1984, the composition  was 88.16 % f i s h  27).  The  r e t u r n i n g t o AB.  o f the r e t u r n i n g marked f i s h ) were  In  straying  9.03 % o f the r e t u r n s born  40.30 % o f the r e t u r n s born i n WB  (1.81  26,  that  among  exchange  was  the  three  greatest  i n AB r e t u r n i n g t o WB and A l l s t r a y s from W (50.0 %  i n t h e WB  area.  A small  percentage  i n the AB spawning  population  t o W.  o f 0.3 year  olds  that o r i g i n a t e d from AB p a r e n t s ,  11.84 % t h a t o r i g i n a t e d from  Figure  1 1 . Egg w e i g h t v e r s u s and the upper and 1982.  female o r b i t - h y p u r a l p l a t e length of s p a w n e r s from W a l k e r Creek l o w e r s e c t i o n s o f t h e s p a w n i n g a r e a i n B u s h C r e e k d u r i n g 1981 and  92 T a b l e 25. S i n g l e degree o f freedom comparisons o f egg weight d i f f e r e n c e s among p o p u l a t i o n s a d j u s t e d f o r c o v a r i a t e u s i n g t h e GT2 Method. (MSD -Minimum S i g n i f i c a n t D i f f e r e n c e ) (* s i g n i f i c a n t d i f f e r e n c e P = . 0 5 ) . Difference Difference Investigated  Temporal  Temporal/ Spatial  Spatial  Among Means  Comparison Difference  WB"  X  X  AB  -0.0202 (0.0111)  X  -0.0087  (0.0109)  -0.0289  (0.0101)  X A B  X  AB"  (MSD)  W  X  w  93  Table 26. The temporal and s p a t i a l and Walker Creeks during 1984 and 1985.  pattern o f return  Recovery Location AB Population of Origin  o f marked  fish  t o Bush  Estimated Total Marks  W3  W  AB  1984,1985 1984,1985 1984,1985  WB  W  1984,1985 1984,1985 1984,1985  AB  15, 3  3, 0  1, 0  201,194  WB  2, 0  3, 0  0, 0  27,  W  0, 0  4, 0  7, 0  0,  1984,1985  40, 0  8, 0  1 9.3 55,0 58  0  40, 0  0, 0  40.3 %  —  0  54, 0  54, 0  50.0 %  -  Table 27. Return rate o f marked f i s h . Ex ani noted for Marks 1984, 1985  Rate of Straying  Population Size Rate of Return 1984, 1985  Population  Nurter Marked  Nutter Recovered 1984, 1985  AB  12,432  19, 3  682,  75  9161, 4842  3.611 %  WB  2,111  5, 0  100,  20  1339, 708  3.171 %  W  8,053  11, 0  150,  20  1150, 200  1.047 %  94  WB p a r e n t s as  and 0 % t h a t o r i g i n a t e d from W p a r e n t s .  AB progeny  1984,  were  composition  recovered.  These  o f 0.3 year  In 1985, o n l y f i s h marked  were a l l observed  t o home t o AB.  In  o l d s i n t h e WB spawning p o p u l a t i o n was 29.85 %  f i s h t h a t o r i g i n a t e d from AB p a r e n t s , 29.85 % t h a t o r i g i n a t e d from WB p a r e n t s , and olds  40.30 % f i s h  t h a t o r i g i n a t e d from W p a r e n t s .  i n the W p o p u l a t i o n  fish originating  was 12.90 % f i s h  The composition  originating  o f 0.3 year  from AB p a r e n t s ,  from WB p a r e n t s , and 87.10 % o r i g i n a t i n g  0 %  from W p a r e n t s .  DISCUSSION  Spawning under s i m i l a r AB. two  and subsequent conditions.  development  o f t h e embryos  Spawning o c c u r s d u r i n g d i f f e r e n t  As a consequence t h e i n c u b a t i o n environment groups.  contrast  Spawning a l s o o c c u r s  t o the separation  migrate  i n relative  i n time  synchrony.  differing  c o n d i t i o n s , but by v i r t u e common  and l a t e  environment  during  spawning  of their  during  the  occur  seasons i n WB and  g r e a t l y between t h e  seasons i n W and AB.  o f t h e spawning  Thus,  of early  a  spawning  differs  during d i f f e r e n t  offspring  occupy  i n W and WB  populations,  the  In fry  the egg t o f r y phase, the stocks  develop  under  sharply  t i m i n g o f downstream m i g r a t i o n , coastal  juvenile  phase.  The  s y n c h r o n i z a t i o n o f m i g r a t i o n among t h e p o p u l a t i o n s appears t o be t h e r e s u l t o f striking  intrinsic  i n c u b a t i o n r a t e d i f f e r e n c e s between e a r l y  and l a t e  r a t h e r than due t o t h e e f f e c t s o f temperature o r other environmental Significant comparisons  differences between  occurred  spatially  i n adult  and t e m p o r a l l y  between p o p u l a t i o n s s e p a r a t e d by both among p o p u l a t i o n s  and  fry vertebral  separated  space and t i m e .  stocks  effects.  number  populations  in  but not  No d i f f e r e n c e s o c c u r r e d  95  in  length  and  AB  spawners  age  in  at  return  1981  and  of spawners except between the  age  at  return  of  WB  g r e a t e s t d i f f e r e n c e i n morphology o c c u r r e d was  found to be  considerable  with  and  AB  between AB  lengths  spawners  of WB  and  i n 1982.  and W progeny.  s u b s t a n t i a l s t r a y i n g i n t o WB  by  The  Straying  both W  and  AB.  Miller account  and  Spawning  temperatures correlation  the  spawn  at  a  limitations  could  the  streams.  and  in  date  incubation  of  time  differences  the  earlier  than  spawning that  (1984)  the  spawning  Creek  synchrony  My  and of  spawning  period.  those  the  to  suggested  offset  (1984) and  the  Populations  reproducing  timing  ensured  in  that  thermal  However,  timing The  at  two  models  stocks  latest  fry migrations  mean  to  reproduce  relatively  to  predation,  Lake  Brannon  without  a third  spawning  late  case.  Walker  population due  stocks.  to  of  colder  nursery  food  supply  r a t e program observed in  the  o f f r y out  i n the  differences  the  the  differences  the  of  incubation  i s warmer  three. in  a  streams.  (1982)  Creek  of of  in  warmer  Thus, i n c u b a t i o n and  mean  evidence  f r y migrated  Miller  in  temperature  were i n n a t e l y d i f f e r e n t  i s achieved  development among the e a r l y and  presents  that  stress,  Chilko  differences  r e l a t i v e l y synchronous m i g r a t i o n  r e s u l t s present  has  adjusted Brannon  of  stocks.  g r a v e l suggests t h a t the  r a t e program.  be  shelter constraints.  temperature o f i n c u b a t i o n .  Bush  Brannon  minimized  space and  s i m i l a r among  the  and  timing  between  adjustment  lake  is  among  during  streams The  (1982)  f o r the e v o l u t i o n o f v a r i a t i o n i n spawning t i m i n g among sockeye salmon  stocks.  stream  Brannon  the  than  However, rate  of  96  ADULT CHARACTERISTICS  Chebanov sex  ratio,  arrival  (1986) proposed  duration  that  several  factors,  o f t h e spawning p e r i o d , body  and d u r a t i o n  o f stay  such  as spawner  density,  l e n g t h o f spawners, time o f  on t h e spawning grounds  influenced reproductive  s u c c e s s i n Oncorhychus.  The c o n s i s t e n c y o f t h e t i m i n g o f r e t u r n t o t h e spawning grounds to  year  suggests  that  annual  environmental i n f l u e n c e s . Oncorhynchus gorbuscha, (1988) a l s o  suggested  timing  o f spawning  i s somewhat  from year  independent o f  Bams (1976) found t i m i n g o f r e t u r n o f pink t o have  that  a genetic  season  component.  o f spawning  salmon,  Recently, G a l l  was h e r i t a b l e .  et  al.  However, t h e  r e t u r n s o f marked f i s h t o Bush and Walker c r e e k s suggest t h a t s t r a y i n g between streams and seasons o f spawning was a common o c c u r r e n c e i n these streams.  The computed a d u l t freshwater r e s i d e n c e time i s a p p r o x i m a t e l y one week or l e s s so I i n t e r p r e t spawning.  t h e escapement t i m i n g  Freshwater  residence  significantly  l o n g e r than t h a t  hypothesized  t o be r e s p o n s i b l e  lower temperatures the  fish;  (b) weaker  expect  that  of fish  o f t h e Walker i n Bush Creek.  Creek Three  f o r longer p e r s i s t e n c e  population i s  f a c t o r s might be  i n Walker  Creek:  (a)  l a t e r i n t h e spawning season may reduce energy demands upon  demands; ( c ) g e n e t i c would  time  as an approximation o f t h e time o f  flows  i n Walker  Creek  d i f f e r e n c e s between s t o c k s .  f r e s h w a t e r r e s i d e n c e time  time as temperatures  may  became c o l d e r .  within  similarly  reduce  I f (a) were t r u e runs would  energy  then one  increase  C o n v e r s e l y , h y p o t h e s i s (b) would  with  predict  97  a  decrease  residence time  i n freshwater  time decreased w i t h i n  increased  (Table 4 ) .  genetic d i f f e r e n c e s ,  Stream in  residence both  These  time  within  runs  with  time  while  suggest  that  another  data  s u r v i v a l time, as determined  30.5  survival  days  life  time  i n the F i s h i n g  i n the Delta- R i v e r  streams stream  t o Bakkala  varied life  Schroder  the  averaged  (1970)  size  correlated.  River.  Trasky  20.4 days  freshwater  o f chum i n Olsen Creek,  and l e n g t h of  In 1981  i n 1982 r e s i d e n c e factor,  such  as  (1975) examined f a l l chum salmon  that  Average  i n 1973  and  18  i n southeast Helle  life  v a r i e d between  B u k l i s and Barton  while  stream  T h i s would e x p l a i n t h e d i s p a r i t y  (1979), Trasky (1974), B a k a l l a  that  days  was  stream  i n 1974.  Alaskan  coastal  7.5 and 10.8 13.1 days  days.  and 15.9  (1984) h y p o t h e s i z e t h a t  o f freshwater m i g r a t i o n a r e p o s i t i v e l y  freshwater  life  (1979) r e c o r d e d freshwater  A l a s k a t o be between  stream l i f e  stream  (1974) determined  life  from 11.4 days t o 18.3 days.  (1973) determined  length  Helle  Elson  Branch  days at B i g Beef Creek, Washington. river  time.  by t a g r e c o v e r i e s , has been r e p o r t e d  i n 1972 and 21 days i n 1973.  According  with  i s important.  a number o f o t h e r chum p o p u l a t i o n s .  stream  runs  temperature  correlated is  with  negatively  between my r e s u l t s and those o f  (1970) and E l s o n  (1975).  The d i s c r e p a n c y  between my r e s u l t s and S c h r o d e r ' s (1973) may be due t o a t a g g i n g induced d e l a y in  r e p r o d u c t i o n at B i g Beef  sampling  methods.  reflect  differences  Creek  Alternatively, in  o r an undetermined both  freshwater  c o n d i t i o n s between an a r t i f i c i a l  results  survival  could due  systematic bias  i n my  be a c c u r a t e and s i m p l y to  the  spawning channel and n a t u r a l  differences streams.  in  98  Both  genetic  meristic studies  environmental  c h a r a c t e r s among have  incubation salmon  and  shown  stocks  suggested  that  temperatures  vertebral  1975).  averaged this  than  populations of  that  (Lindsey  fewer  gill  spawning  s i n g l e chum salmon c r o s s under from  eggs  derived  incubated  from  eggs  at  early  different  lower  incubated  rakers  than  basis  populations  o f such  o f chinook  variation  Kubo  salmon,  had  spawning  populations  spatially  separated  spawning  chum  stocks.  He  vertebrae  from  a  than  those  However, the g e n e t i c  For example, i n salmonidae the among  tshawytcha  spatially (Seymour  among summer and w i n t e r run s t e e l h e a d t r o u t , Salmo g a i r d n e r i  among  of  and found young d e r i v e d  more  confirmed  Oncorhynchus  vertebral  temperature  early  temperatures.  chum salmon g e n e t i c a l l y based  in  Laboratory  (1950) i n c u b a t e d eggs  temperatures  has been  1988). with  that late  variation  s t o c k s probably spawned at warmer  component has a l s o been shown t o be i m p o r t a n t . genetic  vary  found  temperatures  at higher  influence  (Lindsey  will  (1984)  stocks.  can  fish  counts  Beacham  o c c u r r e d because  late  factors  isolated  1959),  and  (Smith 1969). In  count d i f f e r e n c e s have been confirmed and  among  temporally  separated  p o p u l a t i o n s (Kubo 1950 ; Kubo 1956 ; R i c k e r 1972).  According variation highly  to  Lindsey  of vertebral  correlated  as l a t i t u d e  (1988)  counts  operational  i s temperature.  with temperature  ( L i n d s e y 1988).  the  factor  Vertebral  at spawning time  in  latitudinal  counts  are more  than o t h e r f a c t o r s ,  such  99  A count  simple  relationship  between  temperature  does not  e x p l a i n the  pattern  of  have the embryos  greatest  v e r t e b r a l count  experience  development.  the  The  most  progeny  substantially  greater  environment.  Yet,  magnitude  comparisons among t e m p o r a l l y both  temporal and  Age  at  effort. salmon  spatial  maturity  According stocks  seasonally (1987a)  separated  recorded  spawning  migration  into  age  was  greater  in  the  early  changing age  composition  Fraser fish.  r e t u r n i n g i n 1982  1979,  W  their  regime  populations  during  experience  embryonic  incubation  differences i s less  Sano  The  in  (1966) and  and  exceeded t h a t o f 1981  during  than Helle  in  not  among chum vary  among  Beacham and the  earlier  reproductive  vary  does  Murray  course  arriving  (1977) a l s o found  with time o c c u r r e d  Beacham  r e t u r n may  (1984) and  changed  stocks  has  potential  generally  River.  spawning  the  at  but  Birman  at r e t u r n o f a cohort  (Helle  age  rivers  composition  were r e p o r t e d by  abundance  and  i n s i g n i f i c a n t where there i s  to  However, Beacham  observations  Mean age  related  (1975) the  different  o l d e r than the l a t e a r r i v i n g return  s t o c k s and  WB  comparisons but  their  v e r t e b r a l count  directly  stocks.  that  of  vertebral  I observed.  temperature  separated  differences in  separated  Smirnov  entering  in  and  separation.  is  to  that  difference  temporally  temperature  the  variation  incubation  d i f f e r e n c e among the  subtle of  of  of  fish  later  (1979).  i n Bush Creek i n  1982).  The  were  t h a t mean age ones.  This pattern  of  1982.  number  i n a l l p o p u l a t i o n s but  at  Similar  been r e p o r t e d to i n c r e a s e with  Starr  the  of  cohort  spawners  the mean age  of  100  1982  spawners was l e s s than  1981.  This  suggests t h a t  l e s s l i m i t i n g on age o f r e t u r n than environmental  The  importance  o f age at m a t u r i t y  reflected  i n the g e n e r a t i o n  fecundity  and egg s i z e  time  (Gall  1975).  in an organism whose r e p r o d u c t i v e and  Bossert  avoid  1970).  An e a r l i e r  rainbow  larger  trout  eggs than  rates.  (Salmo  younger  Thus, o l d e r  fish  younger spawners (Shine the  age at m a t u r i t y  given  environment  reproduction  will  of reproductive  1954) and i n c o r r e l a t e d  Earlier  age a t m a t u r i t y  p o t e n t i a l increases  i n the ocean.  fish.  slowly  effort  be  favored  with s i z e  (Gadgil  Recently,  i n rainbow t r o u t factors  fish  time and  (1974) found t h a t  fecundity  The f r y o f the o l d e r  is  responses o f  will  However, G a l l  had a h i g h e r  may produce g r e a t e r  these  f a c t o r s i n f l u e n c i n g growth.  i n terms  gairdneri)  1988).  e f f e c t s may be  reproducer can minimize the g e n e r a t i o n  further risk of mortality  older  (Cole  density  and  produced  had b e t t e r  growth  numbers o f more f i t f r y than the  G a l l et a l . (1988) demonstrated  i s highly  probably  heritable  balance  (h2  each  r  0.38).  other  take p l a c e at the age t h a t r e s u l t s i n t h e g r e a t e s t  that In a  so  that  number o f  o f f s p r i n g produced that reach r e p r o d u c t i v e age.  The  l i m i t e d information  than younger spawners.  a v a i l a b l e suggests t h a t o l d e r spawners are l a r g e r  For example,  Bakkala  (1970) r e p o r t s  fork  female chum salmon as 58.7 cm at age 0.2 and 61.4 cm at age 0.3. salmon had f o r k l e n g t h s  advantage  larger  males  in courtship. had g r e a t e r  Schroder mating  females.  (1981) observed  success  compared  Larger that,  to smaller  of  Male chum  o f 58.5 cm at age 0.2 and 59.9 cm at age 0.3.  females a r e g e n e r a l l y more fecund than s m a l l e r an  lengths  Larger  s i z e may  carry  i n chum  salmon,  males.  During  101  1981  older  spawners. at  age  spawners  However, 1982  (AB  53.84 at length  - 54.3  age  at  and  W  -  0.3,  Individuals  when flows  and  Walker  Creeks  WB  of  0.2  and  53.56 at  56.0 age  - 53.84 at age  at age  0.2  and  0.2  an  early  lower.  advantage  currents  that  run  stocks  Smaller  Smaller  in  occur  0.3, 54.41  little  and  are  55.31  often  s i z e may  fish  may  be  t o a v o i d p r e d a t o r s , such as bears or g u l l s , be  1981  in  1982  migrating later  and  younger  i n the  - 53.42 at age  at  age -  0.3).  54.31  at age  at  0.3,  i n the  smaller  length 0.2  and  Similarly, age  0.2  W - 53.16  and  at  age  year.  pattern  reverses  and  than  later  run  fish  be an advantage e a r l y i n the a b l e to more e f f e c t i v e l y i n s h a l l o w water.  maintaining  r e s u l t s concur with data gathered the  than  WB  (AB  position  Larger s i z e  stronger  a l . (1986)  found  steelhead.  by Berg (1934) and R i c k e r  (1972) but  to  that  than  may  winter  i s similar  age  year  maneuver  against  However, L e i d e r et  t h a t summer s t e e l h e a d t r o u t were l a r g e r at a g i v e n My  larger  0.3).  R i c k e r 1972,). are  were  female spawners d i f f e r r e d only s l i g h t l y  o f male spawners d i f f e r r e d  53.85 at age  (Berg 1934,  Bush  at age  0.3,  age  55.34 at age 0.2  in  found  by  Leider  et a l .  (1986).  Fry C h a r a c t e r i s t i c s  Although  the a d u l t runs from AB  runs the f r y runs i n Bush and the both  f r y reach in  the  the  estuary  timing  of  are a l l o c h r o n o u s  relative  Walker Creek are r e l a t i v e l y  i n one  night  emergence  and  I conclude the  that  subsequent  to the W or  synchronous. there  is a  migration  WB  Since  synchrony into  the  102  estuary.  According  to B u k l i s and  among the summer and Big  Barton  autumn chum s t o c k s  (1984) synchrony of f r y runs i n the  Yukon R i v e r .  occurs  In c o n t r a s t , at  Beef Creek the e a r l y s t o c k progeny emerged 25 to 30 days p r i o r to the  stock o f f s p r i n g the winter  (Koski 1975).  stock  late  However, from spawning to emergence, progeny o f  i n B i g Beef Creek gained  12 to 14 days on the autumn spawned  f i sh.  Godin within  a  migrant the  (1982)  population  that  could  the  have  degree  of  important  synchrony  effects  on  in  the  emergence predation  f r y d u r i n g t h e i r d i s p e r s a l movements from the nest s i t e .  degree  of  synchrony  r a t e o f these Gatto  argued  f r y emergence,  f r y because p r e d a t o r s w i l l  1978).  individuals  in  Hence, and  selective  population  the  the  will  will  be  greater  emerge.  This  rate  The  on  greater  relative mortality  be swamped or s a t i a t e d  pressure  synchrony  lower  timing  on  (Peterman  and  asynchronous  argument  is  easily  extended to p r o v i d e a mechanism f o r f r y m i g r a t i o n synchrony among p o p u l a t i o n s which migrate  through  a common e s t u a r i n e environment  as  must the progeny  of  most a l l o c h r o n i c chum salmon s t o c k s .  Another response Northcote  to  suggestion the  short  (1978) and  i s t h a t synchrony term  Miller  abundance o f and  Brannon  p r e d i c t a b l e p e r i o d s o f maximum secondary temperate  regions  times  fry  of  promote  migration  genetic into  the  o p p o r t u n i t i e s , growth and s u r v i v a l .  of food  f r y migrations i n the  should  estuary.  (1982) have suggested  evolve  Bams  (1969),  that seasonally  p r o d u c t i o n i n c o a s t a l marine areas  differentiation nursery Healey  habitat  for  predictable  which  (1979) and S i b e r t  in  maximize  of  optimal feeding  (1979) performed  103  cooperative migration  studies  on  the  d e n s i t y of the  which  showed  that  the  seasonal  Nanaimo River corresponded c l o s e l y  f i s h ' s p e r f e r r e d e p i b e n t h i c prey  into  the  estuary  An  optimal  maximizing  with  and  of  seasonal  on e s t u a r i n e mud  . Walters et a l . (1978) combined the p r e d a t i o n computer s i m u l a t i o n s .  pattern  chum  patterns  marine  survival  f e e d i n g hypotheses u s i n g  was  and  suggested  for  entry Fraser  River chum salmon f r y . , P r e d i c t e d o p t i m a l mean date c o i n c i d e d c l o s e l y with known peak time o f abundance of chum salmon  of  flats.  mean time o f downstream m i g r a t i o n  early  fry  f r y i n the  Fraser  River  the  estuary.  Walters et a l . ' s (1978) model suggests t h a t the lower s u r v i v a l o f f r y e n t e r i n g the  estuary  on  zooplankton side spend  of  the  d e n s i t i e s d u r i n g these  the  a  either side of  optimum  longer  grow  period  at  optimal  date  i s due  to  non-optimal p e r i o d s .  more  slowly  risk  from  becuase  of  lower  at the optimum date.  T h i s model a l s o p r e d i c t s that  variance  about  of  survival. migration o f being  i f the  entry  the  ration  and  lower  the  the  to f r y  greater  subsequent  thus  the  aggregate  narrow time window i s a v a i l a b l e f o r downstream  f r y wish to procure  adequate food  and  reduce the  probability  eaten.  salmon  selection  time  Thus, a r e l a t i v e l y  Although, coho  mean  surface  mortality relative  migrating  the  lower  I n d i v i d u a l s on e i t h e r  the  size-selective  the  Bilton  smolts  against  (1980) showed  could  greatly  affect  asynchronous w i l d  s u r v i v a l o f pink salmon f r y m i g r a t i n g f r y r e l e a s e d 33 days e a r l i e r .  that  the  timing  survival,  f r y i s scant.  of  the  release evidence  Taylor  at the peak time was  Unfortunately,  the  f r y with  of for  hatchery natural  (1980) found  that  8 times h i g h e r  than  lower s u r v i v a l were  104  also al.  considerably smaller  than  the  o t h e r s at the  (1982) found t h a t i n d i v i d u a l s u r v i v a l  time  of release.  Fresh et  i n c r e a s e d with i n c r e a s i n g numbers of  chum salmon f r y r e l e a s e d .  I n t e r p o p u l a t i o n synchrony if  the eggs are  laid  at the  o f downstream m i g r a t i o n i s not same t i m e .  allochronic  p o p u l a t i o n s suggests  operated  on  the t i m i n g o f f r y runs.  for  f r y run  how  Buklis  and  synchrony  Barton  (1984),  that  stabilizing Two  i s achieved based  on  Synchrony o f  achieved  Late  through  spawning  f r y runs  selection  among s e a s o n a l  choose  locations,  proposed  spring-fed  redd  sites  so  that  the s t o c k s c o u l d a d j u s t t h e i r  rate  to  for  thermal and  both  environments as embryos. types  of  a d a p t a t i o n may  the  from  or  has  chum  effect  of  Amur R i v e r  that  synchrony  development  is  genetic incubation  occupying  These hypotheses  salmon.  c h o i c e by the a d u l t .  Alternatively, compensate  of  the o b s e r v a t i o n t h a t Yukon and  accelerated. program  produced  operates  races  b e h a v i o u r a l a d a p t a t i o n s i n redd s i t e  adults  surprising  a d a p t i v e mechanisms are h y p o t h e s i z e d  autumn chum salmon spawn i n spring-warmed is  that  greatly  different  are not mutually e x c l u s i v e  function i n concert  to  create  the d e s i r e d  phenotype.  B u k l i s and  Barton's  (1984) h y p o t h e s i s  r e c i e v e s some support  from my  data  because Walker Creek i s warmer than Bush Creek d u r i n g the embryonic i n c u b a t i o n period.  On  the  other  i n t r a g r a v e l temperatures temperatures the  late  than  hand  I  found  and  evidence  from  my  t h a t the l a t e s t o c k s were u t i l i z i n g  the v a l u e s recorded  s t o c k s , WB  no  W,  i n the water column.  require substantially  measurements  of  s i t e s with warmer It i s c l e a r  fewer temperature  that  units  to  105  reach  emergence  genetic  than  because  variation  have been  early  when the  f o r the n o n - l i n e a r year  the  stock,  thermal u n i t  AB.  These  a factor  The  i n allowing  are p r o b a b l y  accumulations are a d j u s t e d  response o f the genotype  disappears.  differences  slightly  initial  t o account  t o temperature a l l o f the year to  warmer  regime  i n Walker  Creek  c o l o n i z a t i o n by l a t e spawners but  may this  alone cannot account f o r the p a t t e r n o f f r y run t i m i n g .  Independent stocks  have  i n f o r m a t i o n p r o v i d e d by Smoker (1982) a l s o suggests t h a t chum  the  capacity  to  make  genetic  adjustments  in  incubation  rate.  Smoker (1982) performed l a b o r a t o r y experiments comparing the time to emergence among s e v e r a l  geographically  temperature.  Emergence  s e p a r a t e d chum salmon  time  was  dependent  upon  stocks stock  reared  and  had  at the same an e s t i m a t e d  h e r i t a b i l i t y o f 0.900 (Table 3 i n Smoker 1982).  Koski early years  and  (1975) r e c o r d e d the day-degrees late  the  late  day-degrees required  spawning  to  106  stock emerge.  and  195  chum salmon always In  adjustment  between my of  1968  and  more day-degrees  results  incubation  r a c e s t o the s t a b i l i z i n g downstream m i g r a t i o n .  populations  required  The average compensation by the AB agreement  and  rate  accumulated  at B i g Beef  substantially  1969,  respectively,  Creek.  fewer  Within  accumulated stock  (C) t o emerge than d i d the l a t e  stock.  208  those o f Koski common  the  o f the  early  s t o c k was  is a  by the progeny  a d j u s t e d thermal u n i t s . (1975) suggests t h a t  a d a p t i v e response  s e l e c t i o n p r e s s u r e f o r synchronous  The  genetic  among s e a s o n a l  f r y emergence and  106  Smoker with  egg  (1982) suggested  size.  populations results size  that  I f so, then  c o u l d account  among  egg  size  rate  differences  between  incubation  the populations.  size  i s greater  increasing greater adjusted  female  i n WB  i n AB  length  than  AB  compared  t o WB.  and i n 1981  I speculate  f o r the l e n g t h  covariate an  adjustment  o f egg s i z e  among s t o c k s  optimum  average  towards  rate  o f spawners  egg s i z e  a compensatory  and egg  incubation Relative  increases  with  significantly o f the WB  response  when  by the  The p o s s i b l e  genetic  an optimum  i s supported  by the  isolation  among s t o c k s  and the  i n egg s i z e .  1983 f r y had more v e r t e b r a e  difference  late  However, my  of  was  While the p a t t e r n o f d i f f e r e n c e s among the p o p u l a t i o n s the  and  egg s i z e .  egg s i z e  egg s i z e .  between the degree o f r e p r o d u c t i v e  degree o f s i m i l a r i t y  early  differences  smaller  the s m a l l e r  represents  t o produce  rate  Since  length  that  population  correlation  among  W has a r a p i d  compared t o AB but does not show a c o r r e s p o n d i n g egg  was n e g a t i v e l y c o r r e l a t e d  f o r the d i f f e r e n c e s i n i n c u b a t i o n r a t e .  show no correspondence  differences  incubation  i n the c o n d i t i o n s  than t h e i r p a r e n t s . during  embryonic  remained the same  T h i s probably  development  of  reflects a the  adults  compared t o the f r y .  The and  W differred  progeny. the  direction  o f the v e r t e b r a l count  between  the f r y o f 1982 and the a d u l t s  Two c i r c u m s t a n c e s  estuary  d i f f e r e n c e between WB  or the ocean  T h i s does not appear l i k e l y  could could  produce truncate  as the a d u l t  this  result.  the v e r t e b r a l  and AB or WB  o f 1982 and First, count  their  selection in distribution.  v e r t e b r a l count v a r i a n c e e s t i m a t e i s  107  higher  than the  fry vertebral  count  variance estimate.  Alternatively,  the  observed phenotypes c o u l d be produced by the i n t e r p l a y between the genotype  of  the s t o c k s and the i n f l u e n c e o f year t o year v a r i a t i o n s o f temperature d u r i n g the i n c u b a t i o n p e r i o d .  T y p i c a l l y , the v e r t e b r a l number v e r s u s temperature o f  i n c u b a t i o n c u r v e i n t e l e o s t s i s "V" shaped so t h a t h i g h e r v e r t e b r a l counts are r e c o r d e d at h i g h and low t e m p e r a t u r e s o f i n c u b a t i o n w i t h the i n f l e c t i o n of  low  counts  occurring  G e n e t i c compensatory  at  some  i n t e r m e d i a t e temperature  point  (Seymour  1959).  measures t o i n c u b a t i o n temperature v a r i a t i o n among s t o c k s  p r o b a b l y t a k e t h e form o f phase s h i f t s  i n the "V" or p o s s i b l y d i f f e r e n c e s i n  t h e tangent t o each c u r v e ( F i g u r e 12). G e n e t i c adjustment o c c u r s i n response to  the  average  generations. year  climatic  incubation  temperature  Superimposed  differences  e x p e r i e n c e d among s t o c k s over  on the v a r i a t i o n w i t h i n the system  variability.  Hence,  i s h i g h e r than t h e p o i n t  during of  years  when  intersection  the  many  i s t h e year t o temperature  of  between the c u r v e s  the  r e l a t i o n s h i p between t h e s t o c k s s h o u l d be r e v e r s e d ( F i g u r e 1 2 ) .  However, s u p p o r t f o r t h i s h y p o t h e s i s i s l a c k i n g i n the a v a i l a b l e data.  Naniamo a i r p o r t  period  were  temperatures  lower during  in  r e c o r d s show t h a t 78-79  81-82.  e x p e r i e n c e d by t h e 78-79 and temperatures.  and To  temperatures d u r i n g t h e  higher  during  corroborate  the  79-80  79-80 embryos s h o u l d be  incubation  compared  hypothesis  climate  to  the  temperatures  h i g h e r than  the  81-82  However, the g r e a t e r v a r i a n c e i n the a d u l t v e r t e b r a l c o u n t s  r e f l e c t the temperature f l u c t u a t i o n s betweeen t h e 78-79 and 79-80 seasons.  may  108  • A  67  66  O  • A  -  Z) o  O  •  So -  O  A  <  •  CD 6 4 LxJ  At A  O  hUJ  >  O  ez4  t LATE  EARLY  LATE  81-82  7879-  79  78-  79  80  79-  80  INCUBATION  F i g u r e 12.  TEMPERATURE  Proposed  graphical  vertebral  count program  AB,  WB,  and  circles  = AB,  indicate count  the  W  spawners .  model  during  critical of  of  the  interaction  and temperature 1978-79,  Closed c i r c l e s  response  EARLY  81-82  1981-82.  Triangles  temperature progeny  of incubation  1979-80,  = W,  from  between  = WB.  determining "EARLY"  and  among Open Arrows  vertebral "LATE"  109  The  lack  morphology  of  f i t i n the 1982  probably  reflects  the  discriminant effect  i n c u b a t i o n temperature on body p r o p o r t i o n s (1961) the r e l a t i v e incubation.  Since  proportions  percentage  distinctness  stocks  m i s - c l a s s i f i c a t i o n s occurred  (20.7 the  %).  WB  potential  occur  in  occurring  of genetic  d i s r u p t i v e s e l e c t i o n operates there  i s relative  from  the t h r e e  in  t o Barlow  on the temperature o f  than  1982-83 i n c u b a t i o n  (24 %)  intermediate among  on the f r y morphology. i n morphology  The  fewest  and among AB  this  on these  rates and WB  between W and AB.  Given  result  traits;  could (b)  if  In s e c t i o n 4 I w i l l show  among t h e w i l d  t o sample  phenotypic  quite similar  the s t o c k s  of selection  when compared  o f the  morphology.  and WB  migration  uniformity  populations  variation  According  i s an e s t i m a t e fry  among W  i n two ways: (a) i n t h e absence  that  year  among W and AB (9.35 %) with  f r y are m o r p h o l o g i c a l l y rate  colder  t o the 1983 f r y  i n f r y morphology t o t h i s .  the  of m i s - c l a s s i f i c a t i o h  to  change depending  of misclassifications  among  year  (Barlow 1961).  1981-82 was s i g n i f i c a n t l y  season I a t t r i b u t e the s h i f t  The  will  of  function  populations  f r y samples reared  under  controlled conditions.  Bengtson  e t . a l . (1987)  recorded  influenced  the subsequent  size  menidia.  However,  and Schroder  Fresh  that  the time  o f progeny o f the A t l a n t i c (1987)  found  that  of  spawning  season  siverside,  Menidia  predators  d i d not  choose emergent chum salmon based on s i z e but t h a t p r e d a t i o n r i s k was i n v e r s l y r e l a t e d t o abundance o f f r y .  110  Studies  such  (1981) l i n k optimum life  phenotype  competition  may  Possibly  (1981)  returned  variation  not  be  the  selected  such  Leggett  morphology as  (1981) and  regimes.  for during  food,  the  the  occur  Riddell  However, a narrow  stocks  estuary.  Sea  of  early  Japan  spawning  while  late  could  a f t e r the animals  Asian  chum  spawning  the  reduce  Alternatively,  the s t o c k s occupy somewhat d i f f e r e n t o c e a n i c that  et a l .  the e s t u a r i n e phase of  among  in  on body morphology may  suggested  from  and  to s e l e c t i v e  i n body  resources,  selection  estuary.  of R i d d e l l  Variations  for  disruptive  those  morphological  history.  Birman  as  leave  the  environments.  salmon  populations  populations  occupied  a  d i f f e r e n t p a r t of the ocean.  Quinn history that  (1984)  tactic  straying  streams  and  hypothesized  to homing. should be  in  species  that  Quinn  (1984) and  relatively and  straying  could  Quinn and  populations  streams that  would on o c c a s i o n e x p e r i e n c e winter  evolved  i n response  There from  the  are  flow w i l l be  between the  to i n s t a b i l i t y  of  marked  Bush and  population  many problems i n  recovery  differently  nearby streams.  spawning  similar  observed  underestimated.  The  Tallman  in  and  in unstable  geographically  freshets.  life  (1987) p r e d i c t e d  Walker Creeks are  i n Bush  interpreting  individuals.  I f marked  recovery  alternative  simple  first  order  The high l e v e l s o f  Walker Creeks may  have  o f the spawning environment.  than unmarked i n d i v i d u a l s .  be o v e r e s t i m a t e d .  an  common i n p o p u l a t i o n s spawning  streams with  straying  be  of  indirect Marked  I f marked individuals  marked  measures of individuals  individuals stray  individuals  less  gene may  stray  behave  more gene  gene flow  does not  flow  will  necessarily  111  mean t h a t these only  a  i n d i v i d u a l s had been s u c c e s s f u l i n f i n d i n g  limited  number  i n d i v i d u a l s were spent  of  marks  were  recovered  many  a mate.  Although,  of  recovered  the  s u g g e s t i n g t h a t the f i s h had spawned with o t h e r f i s h i n  the p o p u l a t i o n .  Straying (1980  cited  rates  among  in Lister  populations  et a l . 1981) recorded  salmon f r y at Disappearance strayed  other  Creek, southeast  from the Beaver F a l l s Hatchery  was a t r a n s p l a n t ) .  Chum salmon  o f chum  salmon  no s t r a y s from Alaska.  vary.  Freitag  r e l e a s e s o f chum  Fourteen  release s i t e i n Alaska  o f 159 r e t u r n s  (note t h i s  stock  r e t u r n i n g t o Inches-Barnes Creek i n B r i t i s h  Columbia s t r a y e d t o nearby streams at a r a t e o f 1% ( L i s t e r e t a l . 1981).  Year  to year  into  variation  the North one  i n straying  rates  predictability  A high flow.  Creek, B r i t i s h  Columbia  and South A l o u e t t e R i v e r s were h i g h l y v a r i a b l e ranging  year t o 9% i n another  straying  r a t e s from Blaney  (Lister  relative  to  e t a l . 1981).  season  of  r e f e r t o Quinn and Tallman  level  Dowling  of straying  and Moore  from  46?o i n  For a d e t a i l e d d i s c u s s i o n o f  reproduction  and  environmental  (1987).  does not n e c e s s a r i l y mean  (1985) demonstrated  that  that  hybrids  there  may  i s gene  be s t r o n g l y  selected against.  My spatially are  results  and t e m p o r a l l y  separated  outcome  indicate  by both  of genetic  that  vertebral  separated  phenotype  differs  among  p o p u l a t i o n s but not among p o p u l a t i o n s  space and t i m e .  adjustment  count  among  that  I b e l i e v e t h i s p a t t e r n r e p r e s e n t s the the populations  to a t t a i n  an  optimal  112  phenotype  r a t h e r than  solely  the e f f e c t  o f i n c u b a t i o n environment  on s i m i l a r  genotypes.  Significant  d i f f e r e n c e s were found  i n s i n g l e degree o f freedom t e s t s f o r  the 1982 age d i f f e r e n c e s and the 1981 l e n g t h d i f f e r e n c e s i n comparisons among stocks  with  temporal  differences, only.  The most  between the two s t o c k s t h a t are most l i k e l y genetically, different. by  and  AB.  None  I b e l i e v e t h a t these  proposing  flourish.  W  that  stabilizing  of  isolating  by the s t o c k s factors  these  selection  comparisons  were  stocks  significantly  are best  encourages a p a r t i c u l a r  explained  phenotype t o  t o compensate f o r environment d i f f e r e n c e s  are s e l e c t e d a g a i n s t .  among  comparison i s  t o have the o p p o r t u n i t y t o d i v e r g e  s i n g l e comparison r e s u l t s  The genotypes which f a i l  experienced  interesting  are  T h i s system works best  effective  as  among  the  AB  when  and  W  populations.  In  the absence  populations among  of  requires  that  the p o p u l a t i o n s  return  o f marked  substantial.  less  (Spieth  fish  successful  than 1974).  suggests  that  trait  one i n d i v i d u a l The s p a t i a l gene  flow  differentiation per g e n e r a t i o n  and temporal  among  these  among migrate  pattern of  populations i s  In p a r t i c u l a r , t h e WB p o p u l a t i o n r e c e i v e s m i g r a n t s from both t h e  AB and W p o p u l a t i o n s . phenotypically  they  appears  the most  t o be  probability  selection  While  clearly  of survival  AB and W have have  unusual o f an  the most  not i n many o f t h e group  individual  traits. i n terms  depends  g e n e t i c program t o compensate f o r the e f f e c t  opportunity  upon  The  WB  to diverge population  o f phenotype. the a b i l i t y  The  of h i s  o f the i n c u b a t i o n environment t o  113  produce unfit  the  optimal  genotypes  so  phenotype. that  the  In  complete  mean genotype  isolation  of  a  selection will  population  will  approach  adaptive  peak. However, immigration  o f genes from other  populations  genetic  program  compensate  different  environment greatest  has  will  adapted  result  potential  in  evidence this  relative t o the  result  away  of  less  of  fry  for  from  in  model suggested  puzzling  but  predictions  may  be  temperature  and  development  I order  expectation  the  to t e s t  made  it  of with  also  egg  size  comparisons.  temperature i s simple number  and  models  exist.  and  temperature In  traits  that  The  trait  respect  f o l l o w s : (1)  (2) v e r t e b r a l number comparisons; and  optimum. from  morphology  f o r the  must  regarding  results as  the  f i t genes  the  incubation WB  other  has  the  populations  to  of  simple  and  my  ability  to  r a t e and  some  is  t h a t the  well  generate  of  my  strongest between  a  fry migration  rate  to  understood.  comparisons, age  r e l a t i o n s h i p between The  relative  relationship  is  (3) m o r p h o l o g i c a l  incubation  contrast,  I consider the  contrary  I acknowledge t h a t  considered  where  incubation  w e l l understood.  represents  system.  be  h i e r a r c h y o f importance o f v a r i a b l e s measured.  Thus,  a  where  an  size.  intermediacy  general  is  movement  in-migration  r e l a t i v e to i t s p o p u l a t i o n  The  to  remove  clear  timing;  at r e t u r n  incubation  and  r e l a t i o n s h i p between v e r t e b r a l  complex  but  r e l a t i o n s h i p between  reasonable body  predictive  morphology  and  temperature e x i s t s but p r e d i c t i v e models have not been developed.  I  believe  differences  that  i n nature  the  propensity  has  prevented  of  ecologists  to  look  for  phenotypic  i n v e s t i g a t i o n of a s i z a b l e p o r t i o n o f  the  114  genetic each  variation  other  by  among p o p u l a t i o n s .  utilizing  Breeding  particular  reproduction.  Their  different  environments, o f t e n mingle  local  progeny,  d u r i n g the n o n - r e p r o d u c t i v e eliminate  those  the  populations  for  phenotypic  Ecologists  formulate  without  those  phenotypes be  cannot  i n the embryonic uniformity  sites  gone  will  their  view  lives.  manifest  and  embryonic  i n genetic  by  the absence  o f phenotypic  of  ectotherms  environment  Thus, the p r e s s u r e  change  processes  Yet, genetic  for  development i n  among  by measurement  1977).  space  f o r the d i f f e r e n c e s among  environment.  o f the world  from  Stabilizing selection will  compensate  c o n s i d e r a t i o n o f the u n d e r l y i n g (Stearns  time  i n a common s e l e c t i v e  incubation result  in  through  phases o f t h e i r  genotypes which  often  may  having  local  groups i s o l a t e themselves  which  populations.  o f phenotypes, have  d i f f e r e n c e s among difference  generated  populations  rather  than i t s  presence.  Populations greatly  i n the thermal  Temperature phenotypic  incubation  is a  during  different  environments experienced powerful  environmental  seasons by t h e i r  influence  Many c h a r a c t e r s  will  be c o n s t r a i n e d  by s t a b i l i z i n g  i n d i v i d u a l s who can g e n e t i c a l l y compensate f o r the e f f e c t  of incubation w i l l genetically phenotype seasonal  differ progeny. on  many  c h a r a c t e r s such as time t o emergence, v e r t e b r a l number and e x t e r n a l  morphology. that  of  incubation  spawning  persist.  i n incubation f o r downstream  races  Seasonal rate  races  i n response  f r y migration  o f temperature  o f chum salmon appear t o d i v e r g e to constraints  timing.  v e r t e b r a l count and egg s i z e  s e l e c t i o n so  I  stabilizing  speculate  i s also phenotypically  that  the among  stabilized  115  by  an  underlying  races may  genetic  compensation.  have a g e n e t i c b a s i s .  These  results  suggest  that  seasonal  116  SECTION A  INNATE VERSUS ENVIRONMENTAL  CONTROL OF PHENOTYPE  AMONG SEASONAL ECOTYPES  INTRODUCTION  Reproduction periods season  in  temperate  and l o c a t i o n s r e l a t i v e for reproduction  populations  occurs  within  activities.  characterizes  each  restricted  gene  i t i s generally among  flow  accepted  populations  of selective  species, semi-species  While well  will  vast  pressures  of reproduction  i s not a that hasten  races"  literature  acting  time  place  Deviations  will  necessity  and  among  reduce or prevent  (Mayr  local  them  in fisheries  studies are s c a n t .  on the ecology  or l a c k  adaptation  of genetic  (Endler  1977).  among p o p u l a t i o n s  and the  they  may  become  separate  1983).  and v e r a c i t y o f geographic 1963)  for interpopulation  the r e d u c t i o n  upon  or r a c e s ( S a v i a a t o v a  the e x i s t e n c e  documented  "seasonal  specific  population.  Depending on t h e degree and permanence o f i s o l a t i o n nature  A  restricted  and thus a c t as a b a r r i e r t o gene flow (Mayr 1963).  Although  migration  t o other  i n the season o r l o c a t i o n  cross-mating  divergence  ectotherms  regarding This  and g e n e t i c s  races  genetic  or s u b s p e c i e s i s differences  i s surprising  among  considering the  o f salmonids and the f o l l o w i n g :  117  (a)  embryos  different  by  temperature  fixed early (c)  produced  allochronic  regimes;(b) -many  i n development  stabilizing  in  the  are l i k e l y  characteristics  through combined  selection  u n i f o r m i t y . Genotypes  populations  to experience  o f p o i k i l o t h e r m s are  temperature and g e n o t y p i c e f f e c t s ;  environment  will  encourage  phenotypic  which can compensate f o r the temperature d i f f e r e n c e s to  produce the optimum phenotype w i l l  flourish.  Hence g e n e t i c d i f f e r e n c e s s h o u l d  e v o l v e among s e a s o n a l e c o t y p e s .  The e v o l u t i o n a r y many  processes  behaviour  of  are  a  enantiostatis, experienced thermal  the  be  by embryos  to a  developing  function  must  variation  adaptation  i m p l i c a t i o n s o f a l l o c h r o n y are sweeping c o n s i d e r i n g  of  temperature.  maintained  initiated  throughout particular  average  warmer  average  Phenotypic vertebral observed  than t h a t  temperature  similarity count,  even  egg  thermal  though  regime  than  seasons  may  i s likely,  though  the embryos  length  of  function, differences  be comparable  given  to  the  to  Local  selection  to a j u v e n i l e s t a g e .  and W  populations  AB embryos i n c u b a t e d at a much o f the l a t e r  i n several  at m a t u r i t y  the b r e e d i n g environment  mitosis  o f the s p e c i e s .  t o emergence o f the WB  o f AB even  from  temperature  range  development  between AB and W size,  though  the l a t i t u d i n a l  incubation period  was much s h o r t e r  even  embryo  Conservation  in different  p r e s s u r e f o r a harmonius, e f f i c i e n t  The  poikilothermic  that  spawning  stocks.  other characters,  such as  and  age  differed.  at  maturity,  These  was  observations  suggest t h a t g e n e t i c d i v e r g e n c e i n i n c u b a t i o n r a t e and perhaps v e r t e b r a l count has e v o l v e d among s e a s o n a l l y d i s t i n c t  spawning p o p u l a t i o n s o f chum salmon.  On  118  the other hand, h i g h s t r a y i n g r a t e s among the p o p u l a t i o n s c o u l d homogenize the gene p o o l s . and  late  The d i f f e r e n t  spawning s t o c k s c o u l d s w i t c h  the same genome. the  temperatures  i n early development  To d i s t i n g u i s h between these  performance  o f the p o p u l a t i o n s  development  when  onto d i f f e r e n t  possibilities  reared  among the e a r l y  under  pathways on  one must  similar  compare  environmental  conditions.  W i t h i n a s t a n d a r d environment t h e r e are t h r e e c l a s s e s o f f a c t o r s t h a t may affect  s t o c k performance  effects  : 1) g e n o t y p i c  which may be g e n o t y p i c  environment  interactions.  d i f f e r e n c e s among s t o c k s ; 2) maternal  or e n v i r o n m e n t a l l y  Okazaki  (1981) suggested  chum salmon s t o c k s are g e n e t i c a l l y d i f f e r e n t . been suggested The  incubation  control 1985,  f o r temporally rate  through  stocks  d i f f e r e n c e s among  (Okazaki suggested  and 3) genotype -  spatially  separated  d i f f e r e n c e s have a l s o 1978, K u l i k o v a t o be under  populations  (Beacham  1971).  maternal  and Murray  Smoker 1982).  In many cases single  temperature  relative Such  separated  that  Genotypic  o f chum salmon has been  egg s i z e  induced;  the performance o f p o p u l a t i o n s regime  performances  interaction  example, Beacham  ( i . e Smoker  1982).  o f the p o p u l a t i o n s  may  obscure  (1987) found  growth o f chum salmon.  Levins  environmentally  switches  induced  g e n e t i c c o n t r o l o f morphology.  using a  T h i s can be m i s l e a d i n g  depends on the temperature  relationships significant  have been compared  among  the  regime.  populations.  genotype-environment  (1963) suggested  i f the  For  interaction i n  t h a t under c e r t a i n c o n d i t i o n s  i n development s h o u l d be favored over Recent e x p e r i m e n t a l  strict  studies indicate that  such  119  developmental  switches  p o p u l a t i o n performance (i.  may  which  environment.  is  important  a when  widespread  i s compared  e. Beacham and Murray  the n a t u r a l  be  1986).  Occasionally,  i n a range o f c o n s t a n t temperature  regimes  1986). However, c o n s t a n t thermal regimes are rare i n I t i s important t o s i m u l a t e  seasonally comparing  (Lively  varying  the  regime.  performance  of  the n a t u r a l This  stocks  is  spawning  condition especially  in  different  seasons.  The purpose o f t h i s c h a p t e r i s t o determine i f the p a t t e r n o f p h e n o t y p i c variation  observed  populations. the  i n the w i l d  To a c h i e v e t h i s  relative  importance  i s due  to d i f f e r e n c e s  I r e a r e d progeny of  i n the genomes o f the  i n the l a b o r a t o r y  genotypic,  maternal  t o determine  and  interactive  (genotype-environment) f a c t o r s i n the e x p r e s s i o n o f phenotype.  MATERIALS AND  METHODS  Experiment 1 - 1982-83  Eggs and m i l t run  were c o l l e c t e d  i n each p o p u l a t i o n .  stock, stock.  on  Nov.  24,  1982  from spawners near the peak o f the  Gametes were c o l l e c t e d from  the WB  As w e l l , eggs were c o l l e c t e d  to c r o s s with W males.  stock  and  on  Oct. 20,  on Dec.  15,  from females o f the WB  F i v e males and  1982 1982 stock  spawning  from from  the  AB  the W  i n December  5 females w i t h i n each s t o c k were mated  120  in  a l l possible  separately  to  available.  combinations  ensure  Pooling  the milt  to  widest from  produce  25  variability  many males  at 8 C. pooled  form  females and group was  simulated  test  populations.  r e a r e d under  winter  eggs  -  ( to  The  spring  of  1  the  25  t o form  lessening  spawners  of  genetic  fertilized  families  a fourth  generated  test  were  from  5  population.  WB  Each  regimes: c o n s t a n t 6 c e l s i u s , c o n s t a n t  temperature  replicated.  nearest  1.0  Embryos were r e a r e d  embryos  Dechlorinated rate  a  cause  of  f o r 2 hours, then the f a m i l i e s  progression.  were  exposed  Naniamo tapwater was to  saturation. temperatures  1.5  L/min.  Loading were  recorded  twice  n e c e s s a r y ) each week. V a r i a t i o n i n F i g u r e 13.  population  mg) on to  (Rugh 1952). was  measured  screens the  eggs per  The b l o t - d r y using  in c i r c u l a r  surrounding  a 45  weight  top-loading 1  light  fiberglass conditions.  sprayed onto the s u r f a c e o f each tank at a  Oxygen  densities  Each  A sample o f 10 water-hardened  preserved i n Stockard's s o l u t i o n  electrobalance. tanks.  number  made  a s i m u l a t e d autumn - w i n t e r - s p r i n g temperature p r o g r e s s i o n and a  female was these  the  were  1988).  well,  four temperature  temperature treatment was  of  As  5 W males were combined  10 c e l s i u s ,  Crosses  t r a n s p o r t e d t o the l a b o r a t o r y on i c e . Eggs were  The zygotes were water hardened to  with  can  v a r i a t i o n due to sperm c o m p e t i t i o n ( W i t h l e r  The spawn was  families.  c o n c e n t r a t i o n s were  averaged weekly.  about  1000  90  %  eggs/tank.  Temperatures  from the planned temperature  Mean temperatures f o r each c e l l  above  were  Water  reset  regimes  are g i v e n i n Table 28.  air  (if  i s shown  121  Dead eggs were removed from each tank and s t o r e d Dead eggs were i n s p e c t e d to determine died  in Stockard's s o l u t i o n .  the stage at development  a c c o r d i n g t o Velsen's (1980) c l a s s i f i c a t i o n .  With  substrate surface The  hatch to  with  a  was  completed  depth  the  of  water  about  the four  o f f f o r 15  alevins cm. minutes  c u m u l a t i v e numbers o f these emerged  was  no  increase.  subtracting When 50 from  the  per  the  Survival  total  from  emerged  for  later  f r y from  were  provided  with  that  remained  at  to  emergence  emerged and  a  or  were c o n s i d e r e d to have  the number  had  measurement  day.  f r y were r e c o r d e d d a i l y  hatch  cent o f the h a t c h l i n g s  tank  Fry  was  i n the  them  gravel  near  the  emerged.  until  there  calculated  by  tray  at h a t c h i n g .  50  f r y at random  in  5  I selected  preserved  they  the onset o f h a t c h i n g  I r e c o r d e d the c u m u l a t i v e number o f hatched a l e v i n s each  Once  at which  %  buffered  formalin.  Experiment 2 - 1983-84  Experiment p r o t o c o l was  2 was  basically  a replication  o f experiment  1 .  However, the  a l t e r e d i n number o f important ways:  1) Eggs and m i l t  were c o l l e c t e d  s t o c k , on December 4, 1983  from spawners on October  from the WB  19, 1983  s t o c k and on December 9,  from the AB  1983  from the  W stock. 2)  After  rather  fertilization  than water  mortality  from  eggs  hardening  vibrational  were moved for 2 shock  directly  hours. that  the  This eggs  into was  their  done  might  incubation  i n order to  have  tank reduce  experienced  the  122  previous year.  A c c o r d i n g t o Jensen  to d i s t u r b a n c e i n c r e a s e s  rapidly  and  and  Alderdice  steadily  (1983) s e n s i t i v i t y  after  fertilization.  o f eggs The  eggs  were then d i s i n f e c t e d u s i n g Erythromycin ( E v e l y n et a l . 1986). 3) The tanks were kept dark throughout the i n c u b a t i o n 4)  Pressure  reducing  v a l v e s were  installed  so  period.  that  incubation  would not f l u c t u a t e as w i d e l y as they had i n 1982-83. adjustments  by  other  experimenters  changes i n the incoming l i n e s t o my warm and  chilled  Pressure  reducing  pressure  changes up  into  lab.  the  water  supplies  valves the  Hence,  do  5) Temperatures  the  After  internal  the  had  hatched  to  the  top  bottle.  of  Thus,  considerably daily  the  count  alevins  further of  stand-pipe  the  t o be  had  to  then  a  set  at the  minimum  stable  between tank.  so  lines  that coming  i n the  r a t h e r than weekly  tanks  i n the  t o ensure t h a t  as  baskets  were  A l e v i n s were dropped  removed  and  i n t o a 4 cm  C o l l e c t i n g b o t t l e s were p l a c e d at f r y had to move from the tank  down  migrate  classified  f r y appearing  to  incubation  Emerging and  pressure  met.  o f the tank.  the end o f the tank d r a i n p i p e .  the temperature  relatively  s t a n d - p i p e s were s e t i n the t a n k s .  l a y e r o f g r a v e l at the bottom  caused  13, Table 28).  were checked and r e s e t d a i l y  embryos  line  the p r e s s u r e i n the  remained  the planned regimes were more c l o s e l y 6)  water  pressure  affect  temperatures  In 1982-83, temperature  T h i s would change the mix  hence a l t e r  not  d u r i n g 1983-84 i n c u b a t i o n s ( F i g u r e  the  tanks.  and  squeeze  line  sharing  temperatures  the  much  drain  more  emergent  collecting  into  vertically  compared  bottle  s u b j e c t i v e measure o f f r y emergence than i n Experiment  the  1.  with  bottom  collecting and  travel  1982-83.  p r o v i d e d a much  A  less  1983-84 10 CELSIUS  1982-83 10 C E L S I U S • • • AB L 16 A 15 B 14 13 T 12 E 11 M P 10 9 0  A  A  A  WB  o o oWB W  * * W  A  9  •  UJ  O  20  40  r!riiT 60  80  0  50  100  D A Y S FROM FERTILIZATION F i g u r e 13.  I n c u b a t i o n temperatures (C) of the 1982-83 and 1983-84 experiments. S o l i d l i n e s represent the planned changes i n temperature regime.  150  124  Mean w a t e r t e m p e r a t u r e s i n each c e l l f o r Table 28. experiments. (Standard Deviation i n Parentheses).  1983-84  Temperature  PopulationTemperature Treatment  1982-83 and  1982- 33  1983--84  (0.73)  6.0 (0.20)  10.8 (1.79)  10.0 (0.14)  AB - EARLY  4.8 (1.78)  4.8 (1.59)  AB - LATE  6.2  (2.24)  6.2 (2.32)  WB - 6  6.7 (1.34)  5.9 (0.14)  10.9 (2.14)  9.9 (0.17)  WB - EARLY  4.5 (1.73)  4.8 (1.62)  WB - LATE  6.1  (2.21)  6.0 (2.26)  WBxW - 6  6.0 (0.41)  AB - 6 AB - 10  WB - 10  6.1  6.1  (0.20)  10.4 (1.58)  10.0 (0.21)  WBxW - EARLY  4.6 (1.66)  4.8 (1.63)  WBxW - LATE  6.2  (2.26)  5.8 (2.19)  W -6  6.0 (0.19)  6.0 (0.19)  10.0 (3.27)  10.0 (0.14)  W - EARLY  4.8 (1.76)  4.8 (1.60)  W - LATE  5.9 (2.14)  5.6 (2.16)  WBxW - 10  W - 10  125  7) General water  system  shutdowns d i d not occur d u r i n g  three i n 1982-83 r e s u l t i n g  1983-84.  There  were  i n sharp temperature s p i k e s i n the i n c u b a t i o n  tank  temperatures.  Statistical  The not  Analysis  individual  hatch and emergence time o f embryos  be independent.  use  the mean  Thus,  hatch  and  to avoid p s e u d o r e p l i c a t i o n , emergence  times  i n each  i n the same tank may  (Hurlbert  tank  as  1984) I w i l l  the measure o f  interest.  D i f f e r e n c e s observed between y e a r s c o u l d more  likely  due t o t e c h n i c a l  chose  to  them  analyze  variance. Y  where  differences  separately  using  be due t o b i o l o g i c a l  f a c t o r s or  i n the experiments.  Therefore I  a  analysis  two  way  factorial  The model used i s as f o l l o w s : ijk  =  u  +  Ai  +  Bj  +  ABij  +  Ei jk  Y -  mean days t o hatch or emergence  u =  the p a r a m e t r i c mean o f the mean days h a t c h or emergence  A =  e f f e c t o f p o p u l a t i o n , i = 1, 4  B =  e f f e c t o f temperature regime j = 1, 4  AB r p o p u l a t i o n by temperature regime E  = e r r o r term f o r the  interaction  k ' t h o b s e r v a t i o n i n tank i j k  of  126  I used the Sum o f Squares Simultaneous Test 1964)  to  compare  populations  regimes w i t h i n p o p u l a t i o n .  within  Procedure  temperature  (Sokal and Rohlf 1981).  and  means may be t e s t e d .  of  interest  between group  were between  AB  and WB  separated  populations  comparison  between two p o p u l a t i o n s  WB  representing  and  W  regimes  and  (Gabriel  temperature  T h i s procedure i s c o n s e r v a t i v e with r e s p e c t t o the  p r o b a b i l i t y o f Type I e r r o r contrasts  (SS-STP)  within  a  representing  the  same  stream;  A l l possible The 'a p r i o r i  a comparison AB  and  W  comparisons comparisons  1  o f temporally representing  with both temporal and s p a t i a l  comparison  between  temporally  similar,  a  isolation; spatially  s e p a r a t e d p o p u l a t i o n s ; AB v e r s u s the average o f WB and W combined, a c o n t r a s t between  the early  spawning  versus the average  population  o f AB and WB,  and the l a t e  a contrast  spawning  populations;  o f the p o p u l a t i o n  W  i n one creek  a g a i n s t the p o p u l a t i o n s i n the o t h e r creek, WB v e r s u s the average o f AB and W, a contrast  between t h e p o p u l a t i o n  with s m a l l eggs and those with l a r g e  eggs;  and comparisons o f the c r o s s , WBxW, with each o f the donors s t o c k s WB and W as w e l l as t h e i r combined  Fluctations within adjusted  each  average.  i n temperature  temperature  t o account  could  regime.  f o r temperature  Mean  bias days  comparisons t o hatch  differences  between and  populations  emergence  by m u l t i p l y i n g  were  the r e c o r d e d  number o f days by the r a t i o o f the expected mean temperature time the observed mean temperature. the comparisons.  The a d j u s t e d mean days t o hatch and emergence were used i n  127  Survival  For three  the purpose o f s u r v i v a l e s t i m a t e s the dead major  intervals  fertilization  to epiboly;  hatch ( V e l s e n 1980).  I  used  of  epiboly  from  fertilization  t o eye pigment  s t a g e ; eye  t o hatch  (Sokal and  and  R o h l f 1981)to  hatch  to  emergence  determine  was  to  i f survival  dependent  on  counts  1983-84 experiment. f r y from  Also,  high  the  were  read  from  X-rays  I d e c i d e d i t was  1982-83  mortalities  experiment  in  some  counts was (size  checked range  against 50-70  X-ray cm)  because  cells  the  regime  or egg  temperature the  size.  control  samples and  their  from  replicates.  interaction  on  the  The  the  counts o f was  possibility  poor. that  a  The r e l i a b i l i t y o f the v e r t e b r a l counts o f  against  vertebral  cleared  f r y reared and  effect  vertebral  of  population,  counts  of  for several  stained  P r e l i m i n a r y t e s t s i n d i c a t e d t h a t tank e f f e c t s were minimal. combined  temperature  p r e s e r v e d f r y from  t o compare  increased  vertebral  and  of  unwise  n o n - r e p r e s e n t a t i v e sample would be o b t a i n e d .  weeks  from  Counts  Vertebral  the  stage to  also estimated.  regime, p o p u l a t i o n , season o f r e p r o d u c t i o n , l o c a t i o n o f spawning,  Vertebral  into  hatching:  pigment  S u r v i v a l from h a t c h i n g t o emergence was  the G - t e s t  fertilization  development  embryos were grouped  specimens.  Therefore, I temperature  emergent  fry  was  128  estimated  using  a two way  factorial  analysis  Ai  Bj  of variance.  The model used i s  as f o l l o w s : Y  where  ijt<  Y =  =  u  +  vertebral  +  count o f f i s h  + "  ABij  k reared  +  Ei jk  under temperature  regime j from  population i u =  the p a r a m e t r i c  mean v e r t e b r a l count  A =  e f f e c t o f p o p u l a t i o n , i = 1, 4  B =  e f f e c t o f temperature regime j = 1, 4  AB = p o p u l a t i o n by temperature regime E  I  = e r r o r term f o r the  used  regimes.  the S c h e f f e ' s  The  representing  'a p r i o r i  1  interaction  k'th o b s e r v a t i o n on f i s h i j k  Method  t o compare  comparisons  a comparison o f t e m p o r a l l y  populations  of interest separated  were  within between  populations  between two p o p u l a t i o n s  temporal  representing  temporally WB  and W combined,  late the  similar,  isolation;  spatially  population  versus  against  t h e average o f AB and W,  eggs and those with l a r g e eggs.  the populations  WB  both  between  the average o f  spawning p o p u l a t i o n  the average o f AB and WB,  and  with  a comparison  p o p u l a t i o n s ; AB versus  between the e a r l y  W versus  i n one creek  and W  separated  a contrast  spawning p o p u l a t i o n s ;  WB  AB  w i t h i n the same  stream; AB and W r e p r e s e n t i n g a comparison and s p a t i a l  temperature  and the  a contrast of  i n the other  a c o n t r a s t between the p o p u l a t i o n  creek, with  WB  small  129  External  Morphology  For the  the purpose  populations  alternately length  f i n length  and  wet  mm.  WT  arbitrarily of  following  from preserved  (PFL), (WT)  marks per  was  external  procedure  samples  length  weight  number o f p a r r 0.1  the  ( T L ) , standard  pectoral (BD),  o f comparing  eye  diameter  measured  The  used:  length (ED),  by  head  0.1  gram.  from the v e n t r a l t o d o r s a l s u r f a c e  do  not  report  external  temperature c o n t r o l was  Stepwise traits  separation. populations stratified function  a n a l y s i s was  the p o p u l a t i o n s  The e f f e c t was  the  length  (HD),  Lagler  chosen  A parr  total (SNL),  body  depth  (1958) p l u s  were to the mark was  o f the f i s h .  the  nearest defined  exceeding 40 per  As with  I used  cent this  the v e r t e b r a l counts  1982-83  experiment  because  compared  used t o determine the most important as  well  as  o f i n c u b a t i o n environment by  discriminant  by temperature regime. until  from  were  unsatisfactory.  discriminant  for separating  morphology  f r y among  I measured  depth  as any d i s c r e t e v e r t i c a l bar o f dark pigment  the d i s t a n c e  fish  snout  measurements  c r i t e r i u m t o d i s t i n g u i s h p a r r marks from s p o t s . I  25  (HL),  Hubbs and  length  t o the n e a r e s t  o f emergent  r e p l i c a t e tank.  head  as d e s c r i b e d fish.  was  o f each  (STL),  morphology  the ' m u l t i p l e  estimating  on t h e s e p a r a t i o n  analysis of  the  V a r i a b l e s were added  correlation  was  sample  degree  of  among the populations  i n t o the d i s c r i m i n a n t  coefficient,R2>  remaining v a r i a b l e s with those a l r e a d y e n t e r e d  the  of  each  g r e a t e r than  0.40.  of  the  130  RESULTS  Time t o Hatch  The  frequency histograms o f time  each temperature  regime  t o hatch  among the p o p u l a t i o n s w i t h i n  f o r the 1983-84 experiments  are shown  i n Figures  14  and 15 r e s p e c t i v e l y .  In the 1982-83 experiment regime  ( P  population therefore  < by  0.0001)  had s i g n i f i c a n t  temperature  interpretation  the other f a c t o r  Similarly, temperature interaction here a l s o ,  regime o f each  effect  interaction main  effect  ( P < 0.0001 on  time  occurred  ) and temperature  to hatch. ( P  <  However,  0.0001  in  regime  i s conditional  on the s t a t e o f  the (  P  1983-84 <  experiment  population  P  0.0001)  and  population  by  (  <  0.0001  temperature  (P < 0.0001) had s i g n i f i c a n t e f f e c t s on time t o 50 % h a t c h . interpretation  o f each main e f f e c t  (Table 3 0 ) .  Within  temperature  each  ) and  (Table 28).  the o t h e r f a c t o r  the e a r l y  both p o p u l a t i o n  spawning  treatment  i s conditional  the mean number  s t o c k , AB, and the l a t e spawning  WB,  t o reach 50 % h a t c h d i d not d i f f e r  the  winter-spring  regime  significantly  i n t h e 1982-83 experiment  ),  regime Thus,  on the s t a t e o f  o f days  required f o r  s t o c k o f the same c r e e k , except  at 6 C and under  (Tables  29, 30, and 3 1 ) .  However, i n both o f the s i g n i f i c a n t r e s u l t s the AB s t o c k r e q u i r e d more days t o  131  T I M E T O H A T C H AT 6 C E L S I U S FREQUENCE . 300 -, 700 600 500 -  T I M E T O H A T C H A T 10 C E L S I U S FREQUENCY 800 -, , 700 600 500 -  1982-83, BENCH SIDE  F i g u r e 14.  Time  t o hatch  under  6°C,  10°C, s i m u l a t e d  autumn  spawning  regime, s i m u l a t e d w i n t e r spawning regime f o r AB, WB, W x WB  i n the 1982-83 experiment. .  W, and  132  T I M E TO H A T C H AT SIMULATED WINTER SPAWNED  REGIME  FREQUENCY 300 -,  _96.  100_..J04  108  112  116  120  •124  l  128  l  132  136  .  T I M E TO H A T C H A T S I M U L A T E D A U T U M N S P A W N E D R E G I M E FREQUENCY 800 700 -  70  75  80  85  90  95 DAY  P 0 P  • • •  ' 1982-83,  gure  14  continued  100  105  110  Ml 115  MIDPOINT  2  [XXXI 3  BENCH  SIDE  (777] 4  120  125  133  T I M E TO H A T C H AT 6  CELSIUS  FREQUENCY 800  68  72  76  80  84  92  T I M E T O H A T C H A T 10  96  100  104  108  CELSIUS  FREQUENCY 800  DAY MIDPOINT  POP  2  CXXXl 3  1982-83, WALL SIDE  Figure 14 continued  17771  4  134  TIME TO HATCH AT SIMULATED WINTER SPAWNED REGIME FREQUENCY 800 -i  700 600 J  TIME TO H A T C H AT S I M U L A T E D A U T U M N SPAWNED REGIME FREQUENCY 800 -I • 700 600 500 A  5  0  5  0  5  0  5  6  5  6  5  °  6 DAY MIDPOINT  POP  WmfM ,  2  1982-83, WALL SIDE  F i g u r e 14 c o n t i n u e d  3  CZZ2 4  135  T I M E TO H A T C H AT 6 C E L S I U S FREQUENCY 800 700 600 500 400  VI* 78  80  82  84  86  90  T I M E T O H A T C H A T 10  92  94  96  98  100  7  7 5  CELSIUS  FREQUENCY 800 700 -  6 7  5  0  5  7  0  2  0  DAY MIDPOINT POP  '  O Q 2  EXS2  f777] 4  1983-84, BENCH SIDE  Figure  15.  Time  t o hatch  under  6°C, 10°C, s i m u l a t e d  regime, s i m u l a t e d winter W x WB  autumn  spawning regime f o r AB, WB,  i n the 1983-84 experiment .  spawning W, and  136  TIME TO H A T C H AT S I M U L A T E D WINTER SPAWNED  REGIME  FREQUENCY 800 -, 700 -  T I M E T O H A T C H A T SIMULATED A U T U M N SPAWNED  REGIME  FREQUENCY 800 -i 700 -  68  72  76  80  84  88  92  96  100  104  DAY MIDPOINT  POP'  •  1  CZXZ2 2  SSS 3  1983-84, BENCH SIDE  F i g u r e 15 c o n t i n u e d  r7771 4  108 112  137  T I M E TO H A T C H AT 6 C E L S I U S FREQUENCY 800 -, 700 600 500 -  T I M E T O H A T C H A T 10  CELSIUS  FREQUENCY 800 -,  48  51  54  57  60  63  66  69  72  75  DAY MIDPOINT p  mm  1  c m  2  ESS  1983-84, WALL SIDE  gure 15  continued  3  LZZZI 4  78  138  TIME TO H A T C H AT S I M U L A T E D WINTER SPAWNED FREQUENCY 300  REGIME  -i  TIME TO H A T C H AT SIMULATED A U T U M N SPAWNED REGIME FREQUENCY 800 - i 700 600 -  7  2  75  78  81  84  87  90  93  96  99  DAY MIDPOINT P 0 P  mm  1  2  reXXI  1983-84. WALL SIDE  F i g u r e 15 c o n t i n u e d  3  r7771 4  102  105  139  Table 29. Mean h a t c h t i m e f o r p o p u l a t i o n by temperature regime t r e a t m e n t s i n 1982-83 e x p e r i m e n t . ( S t a n d a r d d e v i a t i o n s a r e i n p a r e n t h e s e s ) . Temperature Regime Population AB  6 101.7  (0.01)  10  EARLY  LATE  56.0 (0.95).  84.4 (0.72)  128.1  (0.22) (1.40)  WB  78.4 (1.31)  57.3  (1.74)  86.9  (2.15)  114.3  WBxW  88.7 (3.50)  59.4 (4.00)  95.9  (5.27)  113.2 (2.00)  W  84.1  53.7 (0.74)  84.2 (1.46)  (0.72)  104.5  (1.34)  T a b l e 30. Mean h a t c h t i m e f o r p o p u l a t i o n by t e m p e r a t u r e regime t r e a t m e n t s i n 1983-84 e x p e r i m e n t . ( S t a n d a r d d e v i a t i o n s a r e i n p a r e n t h e s e s ) . Temperature Regime Population  6  10  EARLY  LATE  AB  96.2 (3.07)  54.4 (0.52)  94.4 (1.23)  130.7 (0.69)  WB  87.8 (1.72)  64.4 (0.66)  86.0 (1.00)  125.2 (1.07)  WBxW  89.1 (6.47)  74.0 (0.83)  100.5 (5.90)  113.5 (0.09)  W  83.7 (0.84)  58.7 (0.93)  80.4 (0.06)  107.6 (0.37)  140  Table 31. R e s u l t s o f comparisons and c o n t r a s t s o f mean t i m e t o 50 % h a t c h among t h e t e s t p o p u l a t i o n s r e a r e d w i t h i n each temperature regime. Mean t i m e t o h a t c h used i n comparisons was a d j u s t e d f o r temperature v a r i a t i o n . A p l u s (+) i n d i c a t e s t h a t t h e p o p u l a t i o n t o t h e l e f t o f t h e minus s i g n took more t i m e r e a c h 50 55 h a t c h t h a n t h e p o p u l a t i o n o r average o f two p o p u l a t i o n s t o t h e r i g h t . (An a s t e r i s k (*) i n d i c a t e s t h a t P < 0.05. Two a s t e r i s k s (**) i n d i c a t e t h a t P < 0.01). TEMPERATURE 6  REGIME  10  EARLY  LATE  Comparsion  1982  1983  1982  1983  1982  1983  1982  1983  AB - WB  + *  N.S.  N.S.  N.S.  N.S.  N.S.  + *  N.S.  AB - W  +  + *  N.S.  N.S.  N.S.  + *  WB - W  N.S.  N.S.  N.S.  N.S.  N.S.  N.S.  + *  N.S.  N.S.  N.S.  AB - (WB + W) 2  +  **  **  +  **  + *  +  **  + *  + *  +  **  W - (AB + WB) 2  N.S.  N.S.  N.S.  N.S.  N.S.  _ *  _ •**  _ *  WB - (AB + W) 2  N.S.  N.S.  N.S.  N.S.  N.S.  N.S.  N.S.  N.S.  (WBxW) - WB  N.S.  N.S.  ' N.S.  N.S.  + *  + *  N.S.  + *  (WBxW) - W  N.S.  N.S.  N.S.  + *  N.S.  +  **  N.S.  N.S.  (WBxW) - (WB + W) N.S. 2  N.S.  N.S.  + *  + *  +  **  N.S.  N.S.  141  reach  50 %  hatch.  As  well,  the e a r l y  spawning  stock required  more days t o reach 50 % hatch than the W s t o c k and the combined late  spawning  s t o c k s under  autumn-winter-spring suggests t h a t  a l l temperature  temperature  the e a r l y spawning  regime  treatments  of  the  s t o c k s at l e a s t  temperatures d u r i n g the e a r l y s t a g e s o f embryonic  In  experiments  temperature  regime  at  6  t h e r e was  C, no  10  C,  and  significant  to 50 % h a t c h between the two  l a t e spawning  stock  more  required  significantly  s t o c k when reared under W stock required  and  to  under  the  difference  slower  s t o c k s , WB  regime  rapid  i n c u b a t i o n r a t e t o hatch o f the Walker  Creek  s t o c k s under  the  winter-spring  incubation  50  autumn-winter-spring  %  However, the  emergence  regime.  than  regime  WB  the W  Similarly,  the  average  i n the 1983-84  i n both experiments.  The more  Creek s t o c k compared t o the Bush  regime  i n c u b a t i n g at c o l d temperatures d u r i n g e a r l y  This  c o n d i t i o n s of c o o l  and W.  the w i n t e r - s p r i n g temperature  the w i n t e r - s p r i n g  the  i n the number o f days  s t o c k s under the autumn-winter-spring  under  and  development.  under  reach  C  fewer days t o reach 50 % emergence than the combined  o f the Bush Creek experiment  days  10  experiment.  s t o c k has an i n t r i n s i c a l l y  r a t e to hatch than the l a t e spawning  average o f the  except  1982-83  significantly  may  reflect  an  adaptation for  development.  Time t o Emergence  The within  frequency  each  histograms  temperature  shown i n F i g u r e  16  and  regime 17.  of  time  f o r the  In the  to  emergence  1982-83  and  among  the  populations  1983-84 experiments  1982-83 experiment  both p o p u l a t i o n  are  ( P <  142  TIME TO E M E R G E N C E  A T (i  CELSIUS  FREQUENCY 300 -j 700 600 500 -  T I M E T O E M E R G E N C E A T 10  CELSIUS  FREQUENCY 800 700 600 -  1982-83, 8ENCH SIDE  F i g u r e 16.  Time t o emergence under 6°C, 10°C, s i m u l a t e d autumn spawning regime, s i m u l a t e d winter spawning regime f o r AB, WB, W, and W x WB i n the 1982-83 experiment .'  143  TIME TO E M E R G E N C E AT SIMULATED WINTER SPAWNED  REGIME  FREQUENCY 300 -, 700 • 600 • 500 -  TIME TO E M E R G E N C E AT SIMULATED A U T U M N SPAWNED REGIME FREQUENCY 800 -, 700 600 500 -  140  144  148  152  156  160  164  168  172  176  DAY MIDPOINT .  POP  • • •  1  CXJ2  .  ESS 3  1982-83, BENCH SIDE  F i g u r e 16 c o n t i n u e d  17771 4  180  184  144  TIME TO E M E R G E N C E  AT 6  CELSIUS  FREQUENCY 800 -, 700 600 500 -  120  124  128  132  136  140  DAY  POP  • • •  1 1982-83,  144  148  152  156  MIDPOINT  2  CSS 3  WALL  SIDE  LZZZJ 4  700 600 500 -  7 6 8  8  7  0  4  8 0  8 6  1  8 2  3  8 8  DAY POP  mmm  1  8  4  4  8 8  8 9  9  0  6  2  1  MIDPOINT  2 1982-33, WALL  gure 16 c o n t i n u e d  6  cvsxi SIDE  3  rzzzj  4  145  TIME TO E M E R G E N C E AT SIMULATED WINTER SPAWNED REGIME FREQUENCY 800  HO  144  148  152  156  160  164  168  172  176  130  TIME TO E M E R G E N C E AT SIMULATED AUTUMN SPAWNED REGIME FREQUENCY 800 700 -  600 500  400  1  300  200 -  100 -  d i l l  JZZL  0 136  140  144  148  152  156  If-*-*  160  164  168  172  DAY MIDPOINT  POP  mm  i  a a 1982-83.  F i g u r e 16 c o n t i n u e d  2 WALL  'ESS SIDE  3  r z z a 4  176  180  146  T I M E TO E M E R G E N C E AT (3 C E L S I U S FREQ'iENC •  T I M E T O E M E R G E N C E A T 10 C E L S I U S FREQUENCY  1983-34,  Figure  17.  BENCH  SIDE  Time t o emergence  under 6°C, 10°C, s i m u a l t e d  regime, s i m u l a t e d  winter  W x WB  spawning  i n the 1983-84 experiment .  autumn spawning  regime f o r AB,  WB,  W  and  147  IMK TO E M E R G E N C E AT S I M U L A T E D WINTER S P A W N E D R E G I M E FREQUEHC <:  _144  147  I50  153  156  159  162  165  168  ...171  174  TIME TO E M E R G E N C E A TSIMULATED A U T U M N SPAWNED  177  REGIME  FREQUENCY 800 700 -  600 500  1  2  8  1  3  2  '36  140  144  148 DAY  POP  • • • 1  F i g u r e 17 c o n t i n u e d  156  160  164  MIDPOINT  Q K 3 2 ' 1933-84,  152  BENCH  CV^Cl 3 SIDE  [7771 4  168  172  148  TIME TO E M E R G E N C E AT 0  CELSIUS  FREQUENCY 300 -,  TIME TO E M E R G E N C E AT 10 CELSIUS FREQUENCY 800 T  106  108  110  112  114  116 DAY  p  H  i  OQ 1983-84,  F i g u r e 17 c o n t i n u e d  118  120  122  124  MIDPOINT  2 WALL  3 SIDE  LZZZJ 4  126  128  149  TIME TO E M E R G E N C E AT .-SIMULATED WINTER SPAWNED REGIME r REO'JENC'.' aoc -, 700 -  riME TO E M E R G E N C E AT SIMULATED A U T U M N SPAWNED REGIME FREQUENCY  1983-84,  F i g u r e 17 c o n t i n u e d  WALL  SIDE  150  0.0001) and temperature regime emergence.  However, p o p u l a t i o n by temperature regime  < 0.0001) and  therefore  interpretation  the s t a t e o f the o t h e r f a c t o r  Similarly, population effect  on  by  population  time  to  50  interaction  emergence  interaction  emergence  o f each main e f f e c t  early  stock,  AB,  the  late  than  i n the  1982  in  (P <  the  i s conditional  on  (P < 0.0001) and  0.001) had  1983-84  i s conditional  required  on  significantly  stock,  experiment  emergence d i d not d i f f e r e a r l y s t o c k needed  a  significant  experiment.  the  state  Thus,  o f the other  WB,  of  more  the  days  same  treatment  significantly  i n the  stream  among AB  and  32, 33 and 34). WB  i n the  under  50  %  the  The mean time to 50 %  10 C t r e a t m e n t .  Also,  the  Creek, W,  under a l l temperature treatments except the  1982-83 experiment.  Similarly,  the e a r l y  stock  took  average o f the  a l l temperature treatments except the 10 C treatment i n the  1982-83 experiment. the  reach  regime and the 6 C  l o n g e r t o reach 50 % emergence than the combined  l a t e s t o c k s under  temperatures,  (Tables  to  s i g n i f i c a n t l y more days t o reach 50 % emergence compared to  the l a t e s t o c k o f Walker C  (P  regime  autumn-winter-spring temperature regime, the w i n t e r - s p r i n g  10  occurred  (Table 3 3 ) .  The  regime  on time to  (Table 32).  regime %  effect  o f each main e f f e c t  (P < 0.0001), temperature  temperature  interpretation factor  (P < 0.0001) had s i g n i f i c a n t  In g e n e r a l , early  emergence than the l a t e  spawning stocks.  when both s t o c k s stock  required  are r e a r e d  under  more  to  days  the same  reach  50  %  151  T a b l e 32. Mean emergence t i m e f o r p o p u l a t i o n by temperature regime t r e a t m e n t s i n 1982-83 e x p e r i m e n t . ( S t a n d a r d d e v i a t i o n s a r e i n p a r e n t h e s e s ) . Temperature Regime 10  Population  EARLY  LATE  AB  152.4 (2.44)  88.7 (0.71)  168.5  (0.56)  173.2 (0.03)  WB  126.8 (2.29)  86.4 (0.03)  169.0  (1.98)  155.7  (0.77)  WBxW  146.7 (2.09)  87.9  170.7  (3.53)  163.0  (2.26)  W  135.3 (0.41)  83.0 (1.74)  (2.53)  149.2 (0.19)  147.2 (0.86)  T a b l e 33. Mean emergence t i m e f o r p o p u l a t i o n by t e m p e r a t u r e regime t r e a t m e n t s i n 1983-84 e x p e r i m e n t . ( S t a n d a r d d e v i a t i o n s a r e i n p a r e n t h e s e s ) . . Temperature Regime Population  6  10  EARLY  LATE  AB  156.5 (3.02)  121.4 (1.35)  166.7 (0.27)  173.4 (0.20)  WB  149.6 (3.89)  122.7 (1.06)  149.7 (4.08)  159.7 (1.08)  WBxW  136.4 (1.99)  109.9 (0.15)  149.6 (4.13)  152.5 (2.29)  W  133.8 (3.42)  110.6 (0.11)  150.7 (1.55)  146.3 (0.02)  152  Table 34. R e s u l t s o f comparisons and c o n t r a s t s o f mean t i m e t o 50 % emergence among t h e t e s t p o p u l a t i o n s r e a r e d w i t h i n each temperature regime. Mean t i m e t o emergence used i n comparisons was a d j u s t e d f o r temperature v a r i a t i o n . A p l u s (+) i n d i c a t e s t h a t t h e p o p u l a t i o n t o t h e l e f t o f t h e minus s i g n took more t i m e reach 50 % emergence t h a n t h e p o p u l a t i o n o r average o f two p o p u l a t i o n s t o t h e r i g h t . (An a s t e r i s k (*) i n d i c a t e s t h a t P < 0.05. Two a s t e r i s k s (**) i n d i c a t e t h a t P < 0.01). TEMPERATURE  6  REGIME  10  EARLY  LATE  Comparsion  1982  1983  1982  1983  1982  1983  AB - WB  + *  N.S.  N.S.  N.S.  + *  +  **  +  **  *•*  N.S.  + *  +  +  **  +  **  N.S.  + *  N.S.  + *  + *  AB - W  +  + *  WB - W  + *  AB - (WB + W) 2  **  N.S. +  1982  1983  + *  + *  + *  **  W - (AB + WB) 2  N.S.  _ *  N.S.  _ *  _ *  N.S.  _  _  WB - (AB + W)  N.S.  N.S.  N.S.  N.S.  N.S.  _ *  N.S.  N.S.  (WBxW) - WB  N.S.  _*  N.S.  _ *  + *  N.S.  + *  N.S.  (WBxW) - W  + *  N.S.  N.S.  N.S.  + *  N.S.  N.S.  N.S.  (WBxW) - (WB + W) + * 2  N.S.  N.S.  N.S.  2  N.S.  N.S.  153  WB the  required  other  late  treatment the  significantly s t o c k , W,  days  required  under  t o reach  by  the  The  to reach 50 % emergence compared to  a l l temperature  i n the 1982-83 experiment  1983-84 experiment.  fewer  more days  treatments  in  Walker  Bush  Creek  stock also  Creek,  WB  and  AB  progression  i n both experiments, under  6 and  and  the  temperature  under  experiment. intrinsically differences stocks.  autumn-winter-spring  This  suggests t h a t  different corresponds  to  the  The l a t e s t s t o c k , W,  10  C  rates.  required average  under  number of  the  regime  days  winter-spring  in  in  in different  However,  differences  significantly  10 C i n the 1983-84 experiment,  s t o c k s spawning  incubation  the  and the autumn-winter-spring treatment i n  50 % emergence than the combined  stocks  except  time  the of  the  1982-83  locations  direction spawning  have  of  the  among  the  r e q u i r e s the fewest number o f days to reach 50 %  emergence.  O v e r a l l , the most c o n s i s t e n t d i f f e r e n c e o c c u r r e d between p o p u l a t i o n s t h a t were s p a t i a l l y  and  temporally i s o l a t e d  or  spawned  at d i f f e r e n t  times  (Table  35).  S u r v i v a l , 1982-83  Survival and  from  temperature  embryos  fertilization  regimes.  surviving  under  t o h a t c h i n g was  Survival the  "Late  rates  varied  Spawned"  embryos s u r v i v i n g under the 6 C e l s i u s regime.  variable from  regime  to  a  f o r the p o p u l a t i o n s low  a  of  high  2-49 of  % of 99%  of  WB W  M o r t a l i t i e s o c c u r r e d throughout  154  T a b l e 35. Summary o f t h e number o f s i g n i f i c a n t c o m p a r i s o n s o u t o f s i x t e e n f o r t i m e t o h a t c h and t i m e t o emergence i n t h e 1982-83 and 1983-84 e x p e r i m e n t s . Comparison  B i o l o g i c a l Meaning  S i g n i f i c a n t Comparisons  AB - WB  Temporal I s o l a t i o n i n Same Stream  AB - W  Temporal and S p a t i a l  WB  Spatial  Isolation  Similar  Timing  - W  Direction  7  +  12  +  8  +  WB - C  1 Parent vs Cross  6  0  W - C  1 Parent vs Cross  4  0  12  +  1 AB - - (WB + W) 2 1 W - - (AB + WB) 2  WB  1 - - (W + AB)  1 WBxW - - (W + WB) 2  Early  vs Late Spawning  Walker vs Bush Creek  8  Small Eggs vs Large Eggs  1  Cross vs Average o f Parents  6  155  the  progression  from  fertilization  to epiboly,  epiboly  t o eye pigment  stage  and eye pigment stage t o hatch (Table 36, F i g u r e 18).  At  6 C most o f the egg m o r t a l i t y  i n the AB and WBxW p o p u l a t i o n s o c c u r r e d  from the eye pigment s t a g e t o hatch (77 % and 70 %, r e s p e c t i v e l y ) . was  fairly  constant  from  fertilization  Survival  t o hatch i n the WB and W p o p u l a t i o n s  ranging from 91.5-95 % i n the former and 99.5-100 % i n the l a t t e r .  At  10 C, under  the "early  spawned" regime and under the " l a t e  regime most o f the egg m o r t a l i t y eye pigment to  stage t o h a t c h .  i n the WB and WBxW p o p u l a t i o n s o c c u r r e d  Survival  was f a i r l y  hatch i n the AB and W p o p u l a t i o n s  regime.  Survival  was a l s o  spawned"  fairly  constant  at 10 C and under  constant  f o r W under  from  from  fertilization  the " e a r l y  spawned"  the " l a t e  spawned"  regime but was lowest from eye pigment stage t o hatch f o r AB.  For pigment  fertilization stage  temperature dependent  to epiboly,  t o hatch  survival  o f incubation  survival  fertilization  depended  to epiboly  location  t o hatch  regime.  o f spawning  survival  (P < 0.01)  t o eye pigment  upon  o f spawning  on  the was  (P < 0.01). except  for  O v e r a l l , from  temperature  and egg s i z e  under  eye  s t a g e under t h e  stage t o hatch at 10 C.  was dependent  and  temperature  and egg s i z e  l o c a t i o n o f spawning  was independent o f season  stage  was dependent  a t each  o f spawning  a t 10 C, e p i b o l y  p o p u l a t i o n , season o f spawning, Survival  Survival  on season  " e a r l y spawned" regime and eye pigment fertilization  t o eye pigment  i n a l l populations  (P < 0.01).  on t h e p o p u l a t i o n ,  Generally,  epiboly  the early  regime,  (P < 0.01). temperature  156  Table 36. S u r v i v a l o f chum salmon f o r each p o p u l a t i o n , temperature r e g i m e , tank and y e a r d u r i n g d i f f e r e n t segments o f embryonic development from f e r t i l i z a t i o n t o emergence. (1)  s  P  R  YR  1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2  1 1 2 2 3 3 4 4 1 1 2 2 3 3 4 4 1 1 2 2 3 3 4 4 1 1 2 2 3 3 4 4 1 1 2 2 3 3 4 4 1 1 2 2 3 3  1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 1 1 1 1 1 1 1 1 2 2 2 2 2 2  82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 82 83 83 83 83 83 83 83 83 83 83 83 83 83 83  N 759 522 934 814 495 337 1006 1019 657 768 543 397 410 548 1018 1039 559 857 566 542 349 429 1007 1020 814 946 624 502 403 777 991 996 1050 1068 1054 1046 472 622 1010 1016 1029 1057 947 1058 542 563  f-ep  N2  0.86 0.93 0.96 0.87 0.99 0.98 0.99 1.00 0.95 0.97 0.93 0.90 0.95 0.80 0.98 1.00 0.96 0.94 0.97 0.88 0.86 0.78 1.00 0.99 0.88 0.61 0.50 0.81 0.96 0.90 0.94 0.80 0.98 0.99 0.98 0.99 0.84 0.57 1.00 1.00 0.99 0.98 0.98 0.98 0.83 0.77  653 486 896 708 490 330 996 1019 624 745 505 357 389 439 998 1039 537 806 549 477 300 335 1007 1010 716 577 312 407 387 700 932 797 1029 1057 1033 1036 397 354 1010 1016 1018 1036 928 1037 450 434  ep-ey 0.80 0.91 0.97 0.86 0.89 0.87 1.00 0.99 0.94 0.91 0.99 1.00 0.97 0.94 1.00 0.99 0.97 0.95 0.96 0.90 1.00 0.83 0.99 1.00 1.00 1.00 1.00 0.06 0.52 0.52 0.93 0.81 0.99 1.00 1.00 0.99 0.98 0.58 1.00 0.98 0.99 1.00 1.00 0.99 0.99 0.75  N3  ey-h  f-h  N4  522 442 870 609 436 287 996 1009 586 678 500 357 378 412 998 1029 521 765 527 429 300 278 997 1010 716 577 312 24 201 364 866 645 1018 1057 1033 1025 389 206 1010 996 1008 1036 928 1026 446 325  0.77 0.77 0.92 0.98 0.70 0.70 1.00 1.00 0.95 0.97 0.81 1.00 0.54 0.98 1.00 1.00 0.98 0.98 0.77 0.93 0.58 0.80 0.99 1.00 0.57 0.70 0.98 0.41 0.76 0.85 0.92 1.00 1.00 1.00 0.98 0.99 0.36 0.76 0.99 1.00 0.99 0.98 1.00 0.99 0.66 0.29  0.53 0.65 0.86 0.73 0.62 0.60 0.99 0.99 0.85 0.86 0.75 0.90 0.50 0.74 0.98 0.99 0.91 0.88 0.72 0.74 0.50 0.52 0.98 0.99 0.50 0.43 0.49 0.02 0.37 0.40 0.80 0.65 0.97 0.99 0.96 0.97 0.30 0.25 0.99 0.98 0.97 0.96 0.98 0.96 0.54 0.17  402 340 800 597 305 201 996 1009 557 658 405 357 204 404 998 1029 510 750 406 399 174 222 987 1010 408 404 306 10 153 309 797 645 1018 1057 1012 1015 140 156 1000 996 998 1015 928 1016 294 94  h-e 0.98 0.97 0.96 0.62 1.00 1.00 1.00 1.00 0.98 0.95 1.00 1.00 1.00 0.99 1.00 1.00 0.98 1.00 1.00 1.00 0.92 0.90 1.00 1.00 0.98 0.99 1.00 1.00 0.98 0.97 1.00 0.95 0.98 0.96 1.00 1.00 0.40 0.32 1.00 1.00 1.00 1.00 0.97 0.99 0.17 0.53  N5 394 330 768 370 305 201 996 1009 546 625 405 357 204 400 998 1029 500 750 406 399 160 200 987 1010 400 400 306 10 150 300 797 613 998 1015 1012 1015 56 50 1000 996 998 1015 900 1006 50 50  157  Table 36. S u r v i v a l o f chum salmon f o r each p o p u l a t i o n , temperature r e g i m e , tank and year d u r i n g d i f f e r e n t segments o f embryonic development from f e r t i l i z a t i o n t o emergence. (1) C o n t i n u e d S  P  R  YR  1 2 1 2 2 1 2 1 2 1 2 1 2  4 4 1 1 4 1 1 2 2 3 3 4 4  2 2 3 3 3 4 4 4 4 4 4 4 4  83 83 83 83 83 83 83 83 83 83 83 83 83  (1)  N 1021 1047 1030 1045 1022 1048 1030 1026 1056 667 583 1023 1038  f-ep  N2  1.00 1.00 0.99 0.99 1.00 0.97 0.98 0.99 0.98 0.50 0.50 0.98 0.99  1021 1047 1020 1035 1022 1016 1009 1015 1035 333 292 1003 1028  ep-ey 1.00 1.00 1.00 1.00 0.99 0.98 1.00 1.00 1.00 0.50 0.40 1.00 1.00  N3  ey-h  f-h  1021 1047 1020 1035 1012 996 1009 1015 1035 167 117 1003 1028  0.98 0.98 1.00 0.99 0.98 1.00 1.00 1.00 1.00 0.48 0.50 1.00 1.00  0.98 0.98 0.99 0.98 0.97 0.95 0.98 0.99 0.98 0.12 0.10 0.98 0.99  N4  h-e  N5  1001 1026 1020 1024 992 996 1009 1015 1035 80 58 1003 1028  1.00 1.00 0.97 0.98 1.00 1.00 0.99 0.98 0.99 0.25 0.60 1.00 0.98  1001 1026 989 1004 992 996 999 995 1025 20 35 1003 1007  (S = Tank) (P r P o p u l a t i o n : 1 = AB; 2 = WB; 3 = WBxW; 4 = W) (R r Temperature Regime: 1 = 6 C ; 2 = 10 C ; 3 = ' E a r l y ' ; 4 r 'Late') (Stages: f-ep = f e r t i l i z a t i o n to e p i b o l y ; ep-ey = e p i b o l y to eye pigment s t a g e ; ey-h = eye pigment stage t o hatch; f-h = f e r t i l i z a t i o n t o hatch; h-e = hatch to emergence)  S U R V I V A L IN L A B O R A T O R Y  FROM FERTILIZATION TO EPIBOLY  Figure  18.  under  EXPERIMENTS 1982-83  Survival 6°C, 10°C, s i m u l a t e d autumn spawning regime, s i m u l a t e d w i n t e r spawning regime for AB WB W, W x WB i n the 1982-83 experiment from to e p i b o l y , e p i b o l y t o eyed and eyed to  and  hatch.fertilLati  S U R V I V A L IN L A B O R A T O R Y FROM EPIBOLY TO EYED,  F i g u r e 18 c o n t i n u e d  EXPERIMENTS  1982-83  S U R V I V A L IN L A B O R A T O R Y FROM EYED TO HATCH,  F i g u r e 18 c o n t i n u e d  EXPERIMENTS  1982-83  161  Survival fertilization populations  100%  hatching  to hatch.  t o emergence  Survival  and temperature  fertilization to  from  t o hatching.  was g e n e r a l l y  of alevins  rates varied  less  than  from  was v a r i a b l e f o r variable  than  from  from 62-96 % f o r WB at 6 C  f o r WBxW and W a t 6 C, WB and W a t 10 C, W under the " e a r l y spawned"  regime and WB under the " l a t e spawned" regime  Survival  from  upon temperature each  t o emergence  regime but was g e n e r a l l y Survival  higher  temperature  hatching  regime  t o emergence  (P < 0.01).  regime  ( F i g u r e 20)  for a l l populations  Survival  was dependent  upon  from  hatching  population,  was dependent  t o emergence a t  season  (except under the " l a t e spawned" regime), l o c a t i o n o f spawning  o f spawning  and egg s i z e (P  < 0.01).  S u r v i v a l , 1983-84  S u r v i v a l from f e r t i l i z a t i o n population population). at  matings  (groups  Survival  ranged  6 C and t h e AB p o p u l a t i o n  compared  t o a maximum o f 98.5  t o hatch r e l a t i v e l y c o n s t a n t among the w i t h i n  where  sires  and dams  were  from  t h e same  from a minimum o f 96.5 % f o r the WB p o p u l a t i o n at 10 C and under  the " l a t e  % shared by W a t 6 C and the  spawned" "late  regime  spawned"  regime and WB under the " l a t e  spawned" regime.  The WBxW c r o s s s u f f e r e d  higher  ranged  % under  mortalities.  Survival  from  10-12  regime t o 50 % under the " e a r l y spawned" regime  the " l a t e  ( F i g u r e 19).  much  spawned"  S U R V I V A L IN L A B O R A T O R Y FROM FERTILIZATION  PERCENT  TO EPIBOLY  EXPERIMENTS 1983-84  SURVIVAL 1 .OOQ  0.67  ON 1X3  0.33  WINTER AUTUMN TEMPERATURE REGIME  0.00  POPULATION  Figure  19.  S u r v i v a l under 6°C, 10°C, s i m u l a t e d autumn spawning regime, s i m u l a t e d w i n t e r spawning regime f o r AB, WB, W, and W x WB i n the 1983-84 experiment from f e r t i l i z a t i o n to e p i b o l y , e p i b o l y t o eyed, eyed to h a t c h .  S U R V I V A L IN L A B O R A T O R Y FROM EPIBOLY  PERCENT  TO EYED,  EXPERIMENTS  1983-84  SURVIVAL  1.00  0.67 •  0.33  WINTER AUTUMN TEMPERATURE REGIME  0.00 WBxW WB POPULATION  Figure  19  continued  S U R V I V A L IN L A B O R A T O R Y FROM EYED TO HATCH,  PERCENT  EXPERIMENTS  1983-84  SURVIVAL  0.67  0.33 -  WI NTER AUTUMN TEMPERATURE REGIME  0.00 WBxW WB POPULAT. I ON  Figure  19 c o n t i n u e d  S U R V I V A L IN L A B O R A T O R Y E X P E R I M E N T S FROM FERTILIZATION TO HATCH,  Figure  20.  1982-83  S u r v i v a l under 6°C, 10°C, s i m u l a t e d autumn spawning regime, s i m u l a t e d w i n t e r spawning regime f o r AB, WB, W, and W x WB i n the 1982-83 experiment from f e r t i l i z a t i o n to h a t c h , h a t c h to emergence, and f e r t i l i z a t i o n to emergence.  S U R V I V A L IN L A B O R A T O R Y FROM HATCH TO EMERGENCE,  PERCENT SURV  gure 20 c o n t i n u e d  EXPERIMENTS  1982-83  S U R V I V A L IN L A B O R A T O R Y FROM FERTILIZATION  F i g u r e 20 c o n t i n u e d  EXPERIMENTS  TO EMERGENCE,  1932-83  168  Mortality to  epiboly,  the  within  i n AB,  epiboly  and W was  t o eye pigment  population  fertilization  WB,  matings.  to epiboly,  relatively stage and  Survival  between  99  and  constant through eye pigment  stage to hatch f o r  varied  between 97.5  and  100  from  to eye  %  epiboly  stage and between 98 and 100 per cent from the eye pigment  Although combined pigment  survival  s t a g e , eye pigment  from f e r t i l i z a t i o n  stage t o hatch depend  p o p u l a t i o n , season o f spawning,  expect  with  e p i b o l y was  high  stable  survival  under  regime; egg  the  regime  and  pigment  'late  spawned'  under  the  stage was  independent  (2) l o c a t i o n o f r e p r o d u c t i o n of  spawned  epiboly  and egg s i z e  and under the ' l a t e spawned under  the  'late  1  Survival  size  fertilization  at 6 C, 10 C, under the  at 6 C,  regime.  from  (2) l o c a t i o n o f under  Survival  the  'early  from  1  (3) egg  size  under  the  spawned' to  eye  10  regime;  Survival  independent o f : (1) season o f spawning  regime; (2) l o c a t i o n o f spawning  spawning  at 6 and  ' e a r l y spawned  to  'early  epiboly  o f : (1) season o f r e p r o d u c t i o n  spawned' regime;  regime,  might  at 6 C and under the  stage t o h a t c h was  to eye  than f o r 1982-83 s u r v i v a l s as one  egg s i z e at 6 and 10 C and under the ' e a r l y spawned' regime.  eye pigment  pigment  upon the temperature  ' l a t e spawned' regime;  'late'  from  0.01)  independent o f : (1) season spawning the  %  ( P <  rates.  spawned' regime and under  100  stage to h a t c h i n g .  to epiboly,  l o c a t i o n o f spawning  t h e r e were more cases o f independence  fertilization  C; (3)  from  at 10 C  at 6 C, 10 C and  'early  spawned'  and  ' l a t e spawned' regime.  S u r v i v a l from f e r t i l i z a t i o n population,  season  o f spawning,  t o hatch was dependent location  o f spawning  on temperature but  there  were  regime, several  169  non-significant 6  and  10 C;  tests.  S u r v i v a l was  (2) l o c a t i o n  independent o f : (1) season o f spawning at  o f spawning  under  the  'early  spawned' and  spawned' regimes; (3) egg s i z e at 10 C, under the ' e a r l y spawned  and  1  'late 'late'  spawned regimes.  Survival survival  from  from  hatching  fertilization  to  emergence  to hatch.  was  Survival  i n most  cases  of alevins  higher  from  than  the, w i t h i n  p o p u l a t i o n matings ranged from 97 % o f AB at 6 C t o 100 % f o r W at 6 C, 10 C and  under  survival  the " e a r l y of  the  spawned" regime, WB  WBxW c r o s s  ranged  from  a t 6 C and 10-18  %  AB  under  at the  10  C.  Alevin  "early  regime"  compared t o 25-60 % under the " l a t e regime" ( F i g u r e 2 1 ) .  Survival temperature  from h a t c h regime  temperature was spawning  (P  t o emergence <  0.01).  a l s o dependent  f o r a l l p o p u l a t i o n s was  Hatch  to  emergence  dependent  survival  at  on each  on p o p u l a t i o n , season o f spawning, l o c a t i o n o f  (except under the " l a t e spawned" regime) and egg s i z e  (except  under  the " e a r l y spawned" regime.  V e r t e b r a l Counts (1983-84 e x p e r i m e n t )  Both p o p u l a t i o n significant regime  ( P < 0.002 ) and  e f f e c t on v e r t e b r a l  i n t e r a c t i o n occurred  temperature regime  number.  ( P < 0.0001  ( P < 0.0001  However, p o p u l a t i o n ) and  therefore  by  had  temperature  interpretation  each main e f f e c t i s c o n d i t i o n a l on the s t a t e o f the o t h e r f a c t o r  (Table 37).  of  S U R V I V A L IN L A B O R A T O R Y E X P E R I M E N T S FROM FERTILIZATION TO HATCH,  PERCENT SURVIVAL  1983-84  O  O .00  1  0.67  -  0.33  WINTER AUTUMN TEMPERATURE REGIME  0.00 WBxW WB POPULATION F i g u r e 21.  S u r v i v a l under 6*C, 10°C, s i m u l a t e d autumn spawning regime, s i m u l a t e d w i n t e r spawning regime f o r AB, WB, W, W x WB i n the 1983-84 experiment from f e r t i l i z a t i o n t o h a t c h , h a t c h to emergence, and f e r t i l i z a t i o n to emergence.  S U R V I V A L IN L A B O R A T O R Y  FROM HATCH TO EMERGENCE,  EXPERIMENTS  1983-84  PERCENT SURVIVAL  1.00O  0.67  n  .33  WINTER A I I T I 11  \  Figure  21 c o n t i n u e d  Ik  1  S U R V I V A L IN L A B O R A T O R Y E X P E R I M E N T S FROM  gure  21  continued  FERTILIZATION  TO  EMERGENCE,  1983-84  173  6 Celsius  Emergent significantly the  fry fewer  same creek  population  and  also  had  spawning p o p u l a t i o n s eggs had  of  the  early  vertebrae from W  than  those  the  (P  <  vertebrae  ( P < 0.05  more v e r t e b r a e  population  than  creek  fewer  spawning  ).  those  of  0.05) than  The  late  (Table  the  Bush  spawning 37).  combined  f r y from  in  The  early  average  with  had  population  the p o p u l a t i o n  from the p o p u l a t i o n s  Creek  of  in  spawning the  with  late  smaller  l a r g e r eggs (P <  0.05).  10 C e l s i u s  There  were  no  significant  comparisons  from a l l t h r e e s t o c k s were s i m i l a r  (Table  or  contrasts.  Vertebral  counts  37).  Autumn-Winter-Spring Regime  Emergent  fry  of  the  early  spawning  population  in  Bush  Creek  had  s i g n i f i c a n t l y more v e r t e b r a e than those o f the l a t e spawning p o p u l a t i o n i n the same creek  (P  vertebrae  than  0.05  The  than  ). those  <  0.05)  the  (Table  combined  f r y from  the  37).  average  The of  population  from the p o p u l a t i o n s with  e a r l y spawning the  with  late  spawning  smaller  population  had  populations  eggs had  l a r g e r eggs (P < 0.05).  fewer  more ( P  <  vertebrae  174  Table 37. Mean v e r t e b r a l c o u n t s f o r p o p u l a t i o n by temperature regime t r e a t m e n t s i n 1983-84 e x p e r i m e n t . ( S t a n d a r d d e v i a t i o n s a r e i n p a r e n t h e s e s , N = 50). Temperature Regime Population  6  10  EARLY  LATE  AB  65.40 (0.871)  65.25 (0.840)  65.80 (0.687)  66.55 (0.876)  WB  66.10 (1.194)  65.25 (0.954)  65.20 (0.758)  67.50 (0.934)  W  66.05 (1.085)  65.50 (0.679)  65.50 (0.816)  65.60 (1.033)  175  Winter-Spring  Regime  Emergent  fry  significantly  of  fewer  the  early  vertebrae  than  spawning  population  those  the  the same creek  and more v e r t e b r a e than  fry  vertebrae  had  fewer  than  from the p o p u l a t i o n with p o p u l a t i o n s with  most  having  similar.  was  the  be  the  least  under  the  vertebral  most  10  from W  o f WB  spawning  (P < 0.05)  and  AB  Creek  in  (Table 37).  W  (P < 0.05).  fewer v e r t e b r a e  than  had  population  those  were the l e a s t s i m i l a r p o p u l a t i o n s w h i l e WB  There, was  labile  The  fry  from  the  no  Celsius but  distinct The  trend  with  one  and W were  population  responses tended to f l i p  back and  always forth.  i n response to temperature regime while W appeared  responsive.  counts  average  s m a l l e r eggs had  higher v e r t e b r a l counts.  WB  those  late  Bush  l a r g e r eggs (P < 0.05).  O v e r a l l , AB and WB the  the  of  in  and  Higher Early  there  was  temperature  i n the  early  Spawning Regime) appeared a  great  deal  of  to  development ( i . e . to  result  population  by  i n lower  temperature  regime i n t e r a c t i o n .  E x t e r n a l Morphology  Stepwise treatments those  of  0.001) but the  two  discriminant  pooled WB  (1983-84 experiment)  and  analysis  r e v e a l e d t h a t AB W.  the  spawning s t o c k s  populations  with  a l l temperature  progeny were m o r p h o l o g i c a l l y  A l l paired population  a marked s e p a r a t i o n  late  of  comparisons  appeared between the  (Tables  38,  39).  distinct  were s i g n i f i c a n t  early  spawning s t o c k  Symptomatic of the  from (P and  relatively  176  Table 38. Approximate transformation F statistic centroids with a l l temperatures pooled. AB WB  78.00  W  119.45  Table 39. Mahalanobis temperatures pooled. AB WB  10.63  W  16.38  to compare population  WB  17.32  distance  between  WB  2.36  population  centroids with a l l  177  greater  morphological  misclassification 40).  The  overlap  among these  between  WB  and  W  was  the  much  higher  two groups by the d i s c r i m i n a n t f u n c t i o n s  d i s c r i m i n a t o r s were  i n order  of value:  ED,  SNL,  PM,  (Table  PFL, HL,  HD,  STL.  The  percentage  misclassifications  f u n c t i o n s were c a l c u l a t e d 41,  42,  early  43,  44).  using  47,  48,  a marked  (Tables  45,  46,  changed  with  the temperature o f  50,  51,  BD, HL, PM, WT  HD,  SNL,  celsius;  regime; and HL, PM,  ED,  eyes,  long  snouts,  stock  deep  heads,  shallow  were i n t e r m e d i a t e  bodies,  WT,  deep  stocks.  52)  occurred  .  The The  important  HD,  PFL, BD  under  between  short  long  discriminantors  heads,  heads, a moderate  of  HL, PFL, SNL,  BD,  spawned"  spawned" regime.  few  parr  had  large  marks  progeny had s m a l l eyes, s h o r t  and  snouts,  number o f p a r r marks and  t o the other s t o c k s .  s h a l l o w heads, shallow b o d i e s ,  the  populations  the "autumn  TL under the "winter  bodies,  (Tables  d i s c r i m i n a t o r s i n order  at 6 c e l s i u s ; ED, PM,  WB  i n weight compared  eyes, s h o r t snouts,  discriminant  r e a r e d at 6 c e l s i u s c h a r a c t e r i s t i c a l l y  heads,  were h e a v i e r than the other deep  HL,  PFL, STL, ED, HD,  Progeny o f the AB  the  o f the l a t e spawning  incubation.  value were ED, SNL, HD, at 10  discontinuity  progeny and those 49,  when  f r y reared under a s i n g l e temperature  In g e n e r a l ,  spawning p o p u l a t i o n s  decreased  W progeny had s m a l l  s h o r t heads, a l a r g e number  o f parr marks and weighed the l e a s t o f a l l the s t o c k s  (Table 53, F i g u r e 22).  Progeny o f the AB s t o c k r e a r e d at 10 c e l s i u s c h a r a c t e r i s t i c a l l y had l a r g e eyes,  many  parr  marks,  intermediate  length  heads,  long  pectoral  fins,  long  178  Table 40. C l a s s i f i c a t i o n m a t r i x f o r 1983 f r y samples u s i n g t h e d i s c r i m i n a n t f u n c t i o n a l l temperatures pooled. GROUP  PERCENT CORRECT  CASES CLASSIFIED INTO GROUP  AB  WB  W  AB  87.0  87  13  0  WB  72.0  6  72  22  W  75.0  1  24  75  TOTAL  78.0  94  109  97  Table 41. C l a s s i f i c a t i o n matrix discriminant function at 6 celsius. GROUP  PERCENT CORRECT  f o r laboratory  fry  samples  CASES CLASSIFIED INTO GROUP  AB  WB  W  AB  92.0  23  1  1  WB  88.0  0  22  3  W  88.0  0  3  22  TOTAL  89.3  23  26  26  using t h e  179 Table 42. C l a s s i f i c a t i o n matrix f o r laboratory d i s c r i m i n a n t f u n c t i o n a t 10 C e l s i u s . GROUP  PERCENT  CASES  CLASSIFIED  INTO  f r y samples  using  the  using  the  GROUP  CORRECT W  AB  WB  25  0  0  AB  100.0  WB  80.0  0  20  5  W  84.0  0  4  21  TOTAL  88.0  25  24  26  T a b l e 43. C l a s s i f i c a t i o n matrix for d i s c r i m i n a n t f u n c t i o n a t E a r l y Regime. GROUP  PERCENT  CASES  CLASSIFIED  laboratory  INTO  fry  samples  GROUP  CORRECT AB  WB  W  AB  100.0  25  0  0  WB  96.0  1  24  0  W  100.00  0  0  25  TOTAL  98.7  26  24  25  180  Table 44. C l a s s i f i c a t i o n matrix f o r laboratory d i s c r i m i n a n t f u n c t i o n a t L a t e Regime. GROUP  f r y samples  CASES CLASSIFIED INTO GROUP  PERCENT CORRECT  AB  WB  W  AB  100.0  25  0  0  WB  92.0  1  23  1  W  84.0  0  4  21  TOTAL  92.0  26  27  22  Approximate Table 45. centroids at 6 C e l s i u s . AB WB  54.46  W  63.97  T a b l e 46.  using the  transformation  F statistic  t o compare  population  WB  10.75  M a h a l a n o b i s d i s t a n c e between p o p u l a t i o n c e n t r o i d s a t 6 C e l s i u s . AB  WB  27.45  W  32.24  Table 47. Approximate c e n t r o i d s a t 10 C e l s i u s . AB WB  67.97  W  71.67  WB  5.42  transformation  WB  6.64  F  statistic  t o compare  population  181  Table 48. M a h a l a n o b i s d i s t a n c e between p o p u l a t i o n c e n t r o i d s a t 10 C e l s i u s . AB WB  34.26  W  36.12  WB  3.35  T a b l e 49. Approximate t r a n s f o r m a t i o n c e n t r o i d s a t E a r l y Regime. AB WB W  F  statistic  t o compare  population  WB  38.25 119.24  51.54  T a b l e 50. M a h a l a n o b i s d i s t a n c e between p o p u l a t i o n c e n t r o i d s a t E a r l y Regime. AB WB W  WB  19.28 60.10  25.97  Table 51. Approximate t r a n s f o r m a t i o n c e n t r o i d s a t L a t e Regime. AB WB  47.49  W  48.37  F  statistic  t o compare  population  ' WB  10.06  Table 52. Mahalanobis distance between population c e n t r o i d s a t Late Regime. AB WB  23.94  W  24.39  WB  5.07  182  T a b l e 53. Means and s t a n d a r d d e v i a t i o n s o f m o r p h o l o g i c a l c h a r a c t e r i s t i c s o f emergent f r y r e a r e d a t 6 c e l s i u s d u r i n g 1983-84 (S.M. Mean s t a n d a r d i z e d t o a common l e n g t h among t h e s a m p l e s ) . POPULATION AB  WB  CHARACTERISTIC  MEAN S.M.  Head Length  83.32 82.28  2. 61  79.40 79.37  1. 83  78. 44 79. 45  2.02  Snout  Length  13.32 13.10  1. 10  10.76 10.76  0. 66  10. 08 10. 21  0.90  Pectoral F i n  42.72  2. 42  39.44  1. 83  38. 64  2.47  Length  42.25  Eye  Diameter  30.28 30.02  1. 13  27.24 27.22  0. 52  27. 24 27. 20  0.96  Depth  45.84 45.06  1. 99  45.12 45.09  1. 52  42. 64 43. 20  1.37  Body Depth  53.28 51.87  4. 31  48.52 48.45  1. 85  47. 68 47. 56  1.45  Head  Weight (mgs)  S.D.  MEAN S.M.  W S.D.  39.34  438.32 64. 96 413.38  MEAN S.M.  S.D.  39. 02  388.60 25. 98 387.55  360. 60 17.03 369. 81  9.60 9.61  1. 18  10.84 10.84  0. 89  11. 80 11. 32  1.40  243.64 239.11  9. 26  242.64 242.03  6. 71  236. 76 241. 95  4.47  46.88 46.43  3. 51  44.72 44.75  3. 10  43. 96 44. 87  3.16  WT/TL  1.17 1.12  0. 14  1.06 1.06  0. 06  1. 00 1.01  0.04  KD (Bams 1976)  2.03  0. 52  1.99  0. 39  1. 97  0.34  Parr Marks  Trunk  Length  Caudal F i n Length  F i g u r e 22.  Schematic drawings t o show the body form of progeny from 6°C treatment of the 1983-84 experiment.  from AB, WB, and W r e a r i n g s  184  snouts,  shallow  intermediate s h o r t snouts, W stock short  bodies  sized  and  eyes,  deep  heads.  few p a r r  marks,  Progeny long  of  heads,  the WB  short  deep bodies and heads o f i n t e r m e d i a t e depth.  had s m a l l  eyes,  pectoral fins,  an i n t e r m e d i a t e  short  snouts,  deep  stock  pectoral  had fins,  The progeny o f the  number  of parr  marks,  bodies  and s h a l l o w  short  heads  heads,  (Table 54,  Figure 23).  When  reared  under  the ' e a r l y '  regime  AB progeny  snouts,  long heads, s h a l l o w heads, long p e c t o r a l f i n s ,  lighter  i n weight.  intermediate  length  The WB progeny had i n t e r m e d i a t e heads,  deep  heads,  had l a r g e  shallow  sized  intermediate  bodies  eyes,  length  W progeny had s m a l l  eyes,  s h o r t p e c t o r a l f i n s , deep bodies  short  snouts,  short  short  snouts, fins,  t o the other  heads, shallow  and were h e a v i e r compared  long  and were  pectoral  bodies o f moderate depth and were o f i n t e r m e d i a t e weight compared stocks.  eyes,  t o t h e other  heads, stocks  (Table 55, F i g u r e 2 4 ) .  Under  the ' l a t e '  long p e c t o r a l f i n s , intermediate  regime the AB progeny  l a r g e eyes,  and deep heads.  l e n g t h , few p a r r marks,  eyes and shallow  heads.  had long heads,  marks,  The WB progeny had heads o f length p e c t o r a l f i n s ,  small  The W progeny had s h o r t heads, many p a r r marks,  short  p e c t o r a l f i n s , s m a l l eyes,  intermediate  few p a r r  and s h a l l o w heads (Table 56, F i g u r e 2 5 ) .  185  T a b l e 5A. Means and s t a n d a r d d e v i a t i o n s o f m o r p h o l o g i c a l c h a r a c t e r i s t i c s o f emergent f r y r e a r e d a t 10 c e l s i u s d u r i n g 1983-84 (S.M. Mean s t a n d a r d i z e d t o a common l e n g t h among t h e s a m p l e s ) . POPULATION AB CHARACTERISTIC  MEAN  WB S.D.  MEAN  W S.D.  MEAN  S.D.  S.M.  S.M.  S.M.  Head Length  82.52 3.58 82.83  84.04 2.82 83.26  81.80 2.77 82.65  Snout  Length  12.96 1.38 13.03  11.60 1.17 11.30  10.76 1.15 10.91  Pectoral F i n  47.40 3.53  40.36 2.56  39.28 2.10  Length  47.61  40.16  39.54  Eye  31.24 0.87 31.30  29.12 1.11 28.90  27.88 1.15 28.10  Depth  47.76 2.14 47.88  46.16 2.62 45.35  44.48 1.94 44.84  Body Depth  45.56 2.35 45.69  47.52 2.84 46.60  45.76 2.46 46.62  340.44 40.61 343.66  361.92 49.41 342.32  339.80 36.47 353.64  Diameter  Head  Weight (mgs)  Parr  Marks  Trunk Length  Caudal F i n Length WT/TL  KD (Bams 1976)  12.08 1.14 12.07  9.32 0.79 9.33  10.40 0.98 10.43  231.48 10.56 232.53  236.68 10.28 232.10  229.56 7.27 232.70  49.12 3.53 49.12  49.44 3.88 49.24  49.12 4.65 49.74  0.93 0.07  0.97 0.10  0.94 0.07  0.94  0.94  0.97  1.91 0.41  1.91 0.46  1.93 0.41  F i g u r e 23.  Schematic drawings to show the body form of progeny from 1 0 ° C treatment of the 1983-84 experiment.  187  T a b l e 55. Means and s t a n d a r d d e v i a t i o n s o f m o r p h o l o g i c a l c h a r a c t e r i s t i c s o f emergent f r y reared under the Early Regime d u r i n g 1983-84 (S.M. Mean s t a n d a r d i z e d t o a common l e n g t h among t h e s a m p l e s ) . POPULATION AB  WB  CHARACTERISTIC  MEAN S.M.  Head Length  89.38 86.84  3.33  83.08 83.47  2.54  75.96 77.58  2.09  Snout  Length  14.84 14.44  1.13  10.88 10.98  1.08  10.52 10.10  0.86  Pectoral F i n  46.56  2.46  40.28  3.12  34.56  2.56  Length  45.39  Eye  Diameter  31.72 31.41  0.78  29.44 29.43  0.91  27.24 27.14  0.52  Depth  48.26 46.54  2.13  45.80 46.03  1.35  41.68 41.28  1.07  51.28  4.14  49.20  1.83  51.08  1.89  Head  Body Depth  S.D.  t  Parr Marks  Trunk  Length  Caudal F i n Length  1.45  243.80 9.23 235.46 51.04 49.07  5.93  MEAN S.M.  S.D.  34.34  51.92  49.46  439.60 70.57 380.95 9.92 9.57  S.D.  40.49  48.02 Weight (mgs)  MEAN S.M.  W  369.40 22.72 37 3.77  374.00 17.02 388.14  9.60 9.66  1.34  11.60 11.91  1.51  236.88 238.84  6.75  237.92 244.73  4.12  47.84 47.77  3.83  43.24 46.17  3.42  WT/TL  1.14 1.03  0.14  1.00 1.01  0.05  1.05 1.05  0.05  KD (Bams 1976)  1.97  0.52  1.94  0.37  2.02  0.37  AB  W CD CO  WB  Figure  24.  Schematic drawings to show the body form of progeny from A B , WB, and W r e a r i n g s from s i m u l a t e d autumn spawning treatment of the 1983-84 experiment.  189  T a b l e 56. Means and s t a n d a r d d e v i a t i o n s o f m o r p h o l o g i c a l c h a r a c t e r i s t i c s o f emergent f r y r e a r e d under L a t e Regime d u r i n g 1983-84 (S.M. Mean s t a n d a r d i z e d t o a common l e n g t h among t h e s a m p l e s ) . POPULATION AB  WB  CHARACTERISTIC  MEAN S.M.  Head Length  88.96 88.41  3.16  81.88 81.60  2.62  81.44 81.77  1.21  Snout  Length  12.92 12.70  1.59  10.12 10.04  1.67  10.68 10.85  0.68  Pectoral F i n  44.56  3.16  37.88  1.99  38.72  1.65  Length  44.03  Eye  Diameter  32.24 32.05  2.20  29.60 29.54  1.03  28.88 28.92  0.66  Depth  51.04 50.54  2.90  47.20 47.06  1.07  45.96 46.07  1.58  Body Depth  51.56  3.80  52.00  1.59  50.36 50.10  1.80  Head  S.D.  Parr  391.08 25.16 386.31  377.64 18.76 383.10  8.84 8.78  1.27  11.00 10.67  1.07  240.72 13.70 236.71  245.32 243.52  6.97  237.04 243.35  5.77  54.60 54.10  5.36  46.60 46.47  4.68  48.52 48.98  3.86  WT/TL  1.08 1.04  0.15  1.05 1.04  0.05  1.03 1.03  0.05  KD (Bams 1976)  1.93  0.53  1.96  0.37  1.97  0.37  Length  Caudal F i n Length  9.48 9.42  S.D.  39.55  51.85  417.04 77.88 395.91  MEAN S.M.  1.62  Trunk  Marks  S.D.  37.67  50.64 Weight (mgs)  MEAN S.M.  W  191  DISCUSSION  To summarize the r e s u l t s :  S u r v i v a l t o hatch  and t o emergence i n the 1982-83 experiment was poor and  h i g h l y v a r i a b l e compared t o t h a t o f the 1983-83 experiment and r e s u l t s o f the other t e s t s must be c o n s i d e r e d with t h i s i n mind.  No s t r o n g l y d e f i n e d p a t t e r n  with  respect  season  size  emerged  t o temperature i n the  regime,  1982-83  p o p u l a t i o n t o t h r i v e stands  populations,  experiment.  hatch  and  populations  regime e x e r t e d  emergence  autumn spawning p o p u l a t i o n interaction  reversed  1982-83  less except  the order  population.  counts  varied  effect  and  the  along  cross-mated  with  hatch  at 10 c e l s i u s  the h i g h  on  The  winter  rates to spawning  and emergence than  where a genotype  isolated  the  the  environment  D i f f e r e n c e s were g r e a t e s t  and s p a t i a l l y  depending  on the i n c u b a t i o n  1983-84.  t o reach  of hatching.  p o p u l a t i o n s t h a t were t e m p o r a l l y  Vertebral  time  of  and egg  and W p o p u l a t i o n s under a l l regimes.  a powerful  i n both  g e n e r a l l y took  failure  out i n the 1983-84 experiment  (96.5% - 98.5%) s u r v i v a l o f the AB, WB,  Temperature  The  o f spawning  among  i n the w i l d .  temperature  regime  or  the  O v e r a l l WB and AB were t h e l e a s t s i m i l a r p o p u l a t i o n s w h i l e WB and  W were the most s i m i l a r but t h e r e was no c l e a r temperature i n the v e r t e b r a l c o u n t s .  linear  t r e n d by p o p u l a t i o n or  192  Discriminant between  a n a l y s i s o f e x t e r n a l morphology  the progeny  diameter,  head  discriminating  o f the autumn  length,  parr  traits.  and longheads compared  The e x p r e s s i o n  marks  For example  stock  showed a s t r i k i n g  and the two  and snout  length  the AB progeny  winter were  separation  stocks.  the most  generally  Eye useful  had l a r g e  eyes  was a l s o dependent  upon  t o t o the W progeny.  o f the t r a i t s w i t h i n  a population  temperature o f i n c u b a t i o n .  S u r v i v a l o f eggs and a l e v i n s among the 1982-83 t r e a t m e n t s d i d not conform to  my  expectations.  F o r example,  I expected t h a t  s t o c k s would s u r v i v e b e t t e r a t 6 C compared  t o 10 C.  eggs i n t h e 1982-83 experiment ranged between t o 90 % at 10 C.  winter  progression  respectively)  spawning  However, s u r v i v a l o f WB  A l e v i n s u r v i v a l was much l e s s at 6 C (62 t o 96 %) Both t h e W and WB eggs had h i g h e r  spring  of late  73 t o 86 % at 6 C compared  to 10 C (100 % ) . -  progeny  than  under  80 %, r e s p e c t i v e l y ) .  o f temperatures  a winter  The g e n e r a l  - spring pattern  t o 75  compared  s u r v i v a l under an autumn -  (72 t o  progression  74  and  98  (2 t o 49  f o r a l l populations  to  99  %,  and 65 t o  i n the 1982-83  experiment was t h a t eggs s u r v i v e d b e t t e r at'10 C and under the ' e a r l y spawned' temperature regime compared  In  general,  among the s t o c k s and  t o 6 C and the ' l a t e spawned' temperature regime.  i n t h e 1982-83 experiment, W eggs compared  w i t h i n temperatures.  had the h i g h e s t  survival  At 10 C, and under the ' e a r l y '  ' l a t e spawned' regimes WB eggs had the lowest s u r v i v a l .  193  Mortalities  could  be  due  embryos when they were added gravel  (Smirnov 1955,  noted t h a t  visible.  After  disturbance. this  cause  (1986a,  not  the  the  would  'eyed'  occur  suggest  survival  other  from  any  The  incubation  eyes  period  in  of  epiboly.  influenced  the  Experiment  are  Beacham  I  The  much  1983-84 1  reared  at  after  Mortalities Deaths lower  experiment  were  Murray  observed  survival.  to  due t o  and  embryos  of  clearly  insensitive  to h a t c h i n g .  development.  into  (1983)  mortality  that  the  the onset  embryo  relatively  mortalities  to  from  the g r e a t e s t  fertilization  of  the  f o r chum salmon  have  compared  conditions  of  were  to  the case  from  shock  Jensen and A l d e r d i c e with time  expect t h a t  might  i n 1982-83 experiment  the  the  additional  factors  one  1983).  fertilization  t o be  vibrational  or when they were t r a n s f e r r e d  stage the embryos might  or  increased  where  throughout development to  eggs  stage  T h e r e f o r e , one  confined  that  to  temperatures.  occurred  t o the t r a y s  o f salmon  1987b) found t h i s  constant epiboly  up  mechanical  Jensen and A l d e r d i c e  sensitivity  fertilization  to  were  overall suggests  sub-optimal.  The  m o r t a l i t i e s a f t e r e p i b o l y c o u l d be due t o the exposure o f the embryos t o l i g h t or  due t o the e f f e c t o f r e a r i n g upon s c r e e n s .  It survival  is  perhaps  by  stocks  embryonic  not and  development  surprising temperature  has  been  that  there  regime.  shown  to  be  is  no  correlation  Heritability less  than  between  of s u r v i v a l  0.05  in  during  Oncorhynchus  ( W i t h l e r et a l . 1987).  The that  relatively  there  is a  poor  survival  fertility  barrier  i n the WBxW c r o s s between  the W  and  i n both WB  years suggests  populations.  This  194  represents  an  unusual  generally  viable  Incompatibility groups. rapid  finding.  even  Intraspecific  when  among  might be r e l a t e d  Although  these  hybrids  different  of  forms  salmonids  (Bakkala  are  1970).  t o the d i f f e r e n c e s i n egg s i z e among the two  populations  tend  t o spawn l a t e  and have  relatively  i n c u b a t i o n r a t e s compared t o t h e AB p o p u l a t i o n they may not be a c h i e v i n g  t h i s through the same means. Beacham and Murray inversely  related  t o the time t o reach  l a t e spawners.  AB c o u l d have developed  for  development  more  rapid  differences results  i n the g e n e t i c  through  different  while  (1986) found  emergence o f the progeny o f e a r l y and s m a l l e r eggs  i n W the change  material means  i n response t o the need may  be more a r e s u l t  i n the n u c l e u s .  the  that egg s i z e was  populations  By  may  achieving  not  be  of  similar  genetically  compatible.  The  presence  of population  by temperature  hatch and emergence time suggests  intrinsically  progeny relative  of  the  the autumn  i n their  spawning  t o the o f f s p r i n g  temperature gap  different  i n the ANOVAs o f  t h a t the s t o c k s are responding  ways t o the v a r i e t y o f i n c u b a t i o n regimes. are  interaction  incubation  stock  o f the l a t e  as opposed t o t h e r e s t  T h i s suggests  appear spawning  t h a t the p o p u l a t i o n s  r a t e program. t o develop stocks  o f the temperature  in different  more  For example, efficiently  at the h i g h regimes.  constant  The g r e a t e s t  between the p o p u l a t i o n s o c c u r r e d under the w i n t e r - s p r i n g p r o g r e s s i o n where late  stock.  season  stocks  developed  much  faster  relative  t o the e a r l y  season  195  The stocks  r e s u l t s show t h a t time to hatch and  t h a t normally spawn d u r i n g  populations  d i f f e r e n t seasons i n the w i l d .  which are both s p a t i a l l y  and  divergence o v e r a l l i n time t o hatch and the of  temporally  temperature  for  that  are  out  The time  stock  then  is significant  temporally  of 12  each  time to emergence.  and  11  the  out  spatially  comparison  of  12  mechanisms  probably  c o n t r o l l i n g these  has  some  in quantitative  traits  that only  a few  genes are  that only  3 loci  regulatory  determined the  insect species.  rainbow  trout  (Salmo  single  regulatory  gene.  Danzmann et  more r a p i d l y . loci  locus  and two  late stocks  is significant  12  could  are  not  involve  involved.  However,  certain.  many  loci  Tauber and  but  gairdneri)  was  c o n t r o l l i n g the  a l . (1986) found that  influenced expression  that  linkage  for i n t r a s p e c i f i c  by of  heterozygous  a the  genetic  Natural  genetic  i t i s possible  Tauber  mutant  (1977) found seasonally  allele  rate at  a  phosphoglucomutase  i n d i v i d u a l s developed  d i s e q u i l i b r i u m between accelerate  and  the  development r a t e d i f f e r e n c e s among  d o m i n a n t - a c t i n g genes t h a t  r a t e are r e s p o n s i b l e  basis.  i n time to hatch  A l l e n d o r f et a l . (1983) found t h a t development  They proposed and  genetic  differences  variation  specific  early  range  times.  emergence  isolated  greatest  the n a t u r a l  comparison  the  eliminates  between the  observed p a t t e r n o f d i f f e r e n c e s among the s t o c k s  to  As w e l l ,  I f one  between  times and  i s o l a t e d the  between  i s o l a t e d show the  10 c e l s i u s treatment on the grounds t h a t t h i s i s o u t s i d e  spawning s t o c k s  in  time t o emergence d i f f e r  or  alleles  at  r e t a r d development  v a r i a t i o n i n incubation  rate.  196  Allendorf  et  al.  confer a competitive  (1983)  advantage  rainbow t r o u t that hatched maturity  sooner  environment hence  than  earlier  growth.  increased  hatch  spring. when  the  the  As  can  well, late  because p r e d a t o r s chum  salmon  fish's  as  a  head  that  their  temperatures  in  I  start  cover  of  aggregated and Finally,  food  on  hatchery  in  rise The  the  and late  is  experience during  the  progressively mortality rate  as a r e s u l t the  a  time a v a i l a b l e  have a h i g h e r  on  sexual  feeding  might  darkness  resources  that  from e x p e r i e n c i n g  stream  experienced  the  observed  n i g h t s become s h o r t e r . the  reached  In  migrants the  could  They showed  progeny  downstream  m i g r a n t s would probably  migrations.  life.  brethren.  allow  to prevent  under  would be  development  time became l a r g e r and  developing  Tardy  migrate  accelerated  r a p i d development  evolved  stress  the  probably  the season p r o g r e s s e s fry  reduced.  slower  disadvantage.  As  throughout  would  However,  thermal  that  at an e a r l i e r  their  spawning s t o c k s p r o b a b l y competitive  suggested  of  estuary  previous could  be  rate  was  d e p l e t e d by e a r l i e r a r r i v i n g f r y .  Adjustment  of emergence t i m i n g through  r e p o r t e d by Beacham and Murray  a change  i n development  (1986a) and Murray and Beacham (1987) f o r e a r l y  and  l a t e spawning s t o c k s o f chum salmon o f the F r a s e r R i v e r .  and  Murray  12  celsius  (1986) a l s o r e p o r t e d between the  no  d i f f e r e n c e i n time t o hatch  progeny o f e a r l y and  C h e h a l i s R i v e r s o f the F r a s e r R i v e r system. spawning hatch  to  post-hatch  populations  differ  emergence. development  In  in  the  genes  c o n t r a s t , my rate  can  However, Beacham  late  T h i s suggests controlling  results  differ  spawners o f  show  among  at 4, the  early  and  Vedder  and  t h a t e a r l y and  development  that  8 ,  both and  rate  pre-hatch late  late from and  spawning  197  populations. Vancouver  Beacham  Island  et  a l . (1985)  were g e n e t i c a l l y  indicated  distinct  that  from  chum  those  salmon  stocks  o f the Fraser  on  River.  Long term i s o l a t i o n o f these major d i v i s i o n s i n the North American Chum salmon p o p u l a t i o n c o u l d e x p l a i n why hatch  time  variability.  The F r a s e r River s t o c k s may not have e v o l v e d the  S e l e c t i o n can o n l y  degree o f i n t r a - p o p u l a t i o n v a r i a b i l i t y environment  remains  stable  and  stabilizing  selection  (Wright  1987).  be e f f e c t i v e  in a trait  predictable  (Falconer  organisms  Thus, g e n e t i c  In g e n e r a l , the m o b i l i t y p r o v i d e d by the a l e v i n stage have  survival  value  areas  when w i n t e r  out.  Where  relatively moderated Island.  i n preventing  f r e s h e t s occur  the stream  free  embryos  from  or when c e r t a i n  pressure.  i n terms o f w i n t e r  will  experience  will  caught  any d i f f e r e n c e w i t h i n  overall  lost.  areas o f the stream the w i n t e r ,  hatch  bed d r y time i s  r i v e r s may be more  the c o a s t a l streams  on  Vancouver  I f the g r a v e l bases are more s t a b l e i n the Vedder and C h e h a l i s R i v e r s  1983-84 experiment, with  show  be  in unsuitable  e a r l y hatch time might not be s e l e c t e d i n the l a t e spawning s t o c k s . the  I f the  i n salmon i s thought t o  The flow o f these  f r e s h e t s than  i s some  1981).  variation  being  bed i s s t a b l e throughout  of selection  i f there  more p r e c i s e c o n t r o l the same  comparison between e a r l y  system  o f temperatures,  f o r time  t o hatch  However, f a i l e d to  although  and l a t e spawners was s i g n i f i c a n t  the  5 out o f 8  times.  A c c o r d i n g t o F. V e l s e n in  incubation  found the  rate  ( p e r s . comm.) t h e r e i s a g r e a t amount o f v a r i a t i o n  t o hatch  among  chum  salmon  stocks.  Smoker  (1982)  also  t h a t time t o hatch d i f f e r r e d among t h r e e chum salmon s t o c k s r e a r e d under  same  conditions.  My  results  support  this  hypothesis  that  hatch  time  198  v a r i e s depending  upon the s t o c k and  Beacham and Murray  (1986a) t h a t  rather  than the h y p o t h e s i s put forward by  incubation  rate  to hatch does not  vary among  chum salmon p o p u l a t i o n s .  My  results  regarding early  differences  and  late  environment celsius well,  generally  the  interaction  stocks. than  showed  differences  temperatures  with  those  of  Beacham  i n time t o emergence under  spawning  treatment  agree  in their  little  in  However,  or no  time  to  are much g r e a t e r than  controlled  I observed  experiments. difference  emergence those  In  I  Murray  (1986)  conditions  among  much more  genotype  particular,  among the  that  that  and  -  the  ten  populations.  As  observed  at  o c c u r r e d among the  the  other  vedder  and  Chehalis River populations.  The observed d i f f e r e n c e s between experiment hatch  and  emerge may  be  the ten c e l s i u s regime. the  high  temperature  accounted Only about  1 and experiment  f o r by temperature  2 i n time t o  o f i n c u b a t i o n except i n  30 per cent o f the d i f f e r e n c e observed at  appears  to  be  can  greatly  directly  a  result  of  mean  temperature  differences.  Emergence  timing  c o n d i t i o n s (Bams 1969,  be  Bams and Simpson 1977).  (1974 i n Bams and Simpson 1977) Simpson 1977)  r e c o r d e d premature  compared to the w i l d s t o c k s . emergence  substantially  altered  the  norm  in  unpublished  d u r i n g development  data).  Mead  Taylor  (1975 i n Bams and  emergence o f p i n k salmon f r y by to l i g h t  suboptimal  For example, B a i l e y and  and B a i l e y , P e l l a and T a y l o r  Exposure  (Bams,  from  and  2 t o 6 weeks may  Woodall  advance (1968)  199  found  that  produced  f r y produced  i n g r a v e l beds.  enter t h e i r two  weeks  1982,  on  lacustrine earlier  pers  Bailey  life  than  emerged 14  to  17  influenced  by  surrounding  found  that  larval  s u r f a c e were l e s s photonegative  and  supported  1986).  sooner  by  than  wild  gravel  fry.  individuals.  periods  were  For  much  and  Finally, example,  shorter  T h i s might  r e s u l t s and those o f Beacham and Murray  Beacham and Murray  (1973) i n d i c a t e t h a t  a  in  account  fry w i l l  emerge one bottom  period  P l y t y e z et  to  (Bams  can  fry be  a l . (1984)  temporaria  reared  f o r d i f f e r e n c e between  (1986).  (1986) r e a r e d embryos i n groups  o f o t h e r s t o c k s (on the same heath  those  unsupported  larval  Rana  than  such  solid  Bams (1982) r e p o r t e d t h a t  i n d i v i d u a l l y r a t h e r than i n groups. my  Heard  p r e m a t u r e l y . A l e v i n s on s c r e e n s may  those  comm. Nortvedt days  a flat  t r a y ) while  o f 10  i n the presence  I r e a r e d the embryos  in large  i n t e r p o p u l a t i o n a l groupings i n s e p a r a t e t a n k s .  The year t o year v a r i a t i o n i n emergence t i m i n g can be p a r t i a l l y e x p l a i n e d by  the d i f f e r e n c e s  i n mean temperature  o f i n c u b a t i o n o f the  first  year  from  the planned v a l u e s .  The e a r l y emergence o f f r y i n c u b a t e d at 10 C e l s i u s d u r i n g  1982-83 c o u l d be due  a synergistic effect  with  the  incubation  temperature warming  and  on  fluctuations. cooling  that  screens  with  from the exposure  minimal  gravel  F l u c t u a t i n g h i g h temperatures would  occur  n a t u r a l emergence p e r i o d f o r these f r y .  during  the  for  to l i g h t , support  combined and  the  c o u l d mimic the d a i l y  spring  months  during  Thus, f r y c o u l d emerge e a r l y .  the  200  The  presence o f s u b s t a n t i a l temperature by p o p u l a t i o n  analysis  of  the  populations  unique g e n e t i c program f o r v e r t e b r a l development.  Populations  different  vertebral  seasons  number  i n the  suggests  same r i v e r  that  interaction  system  v e r t e b r a l counts at v a r i o u s temperatures. between the  early stock  l a t e spawners do not to be a c o n n e c t i o n egg  the  late  stocks  always have h i g h e r  Arnason  meristic character  differentiation,  Model').  and  upon  differentiation  genetic of  the  and  late rays,  chum salmon  Murray  and  Lindsey  et  al.  embryo,  rainbow t r o u t c o u l d  although  response.  the  number  of  influences  the  elements probably (The  on  relative  in  that  emphasize the  " p a r a d o x i c a l " r e a c t i o n i n the  a  growth  'Atroposic may  growth  magnitude  of  be and the  among v a r i o u s c h a r a c t e r s .  a population  f i n rays  found  so  So,  (1986b) found d i f f e r e n c e s among progeny o f e a r l y  pelvic  (1984)  different  v e r t e b r a l number.  independent p r o c e s s e s ,  environmental  spawners w i t h i n  p e c t o r a l and  that  the  their  contrasts  number o f elements i n a m e r i s t i c c h a r a c t e r  environmental component can d i f f e r  Beacham and  in  There a l s o appeared  t h e i r i n t e r a c t i o n s d u r i n g development  V a r i a t i o n i n the  dependent  divergent  v e r t e b r a l counts.  (1981) suggested  i s determined by two  most  a  spawning d u r i n g  were s i g n i f i c a n t l y  between the s i z e of the egg  and  the  possess  However, o n l y h a l f of the  s i z e r a t h e r than genotype c o u l d c o n t r o l the  Lindsey  and  and  are  each  i n the  and  gill  temperature expected  i n dorsal  rakers  but  f i n rays, not  changes d u r i n g  pattern  development program.  among  anal  fin  vertebrae.  development  o f development  and  of  or cause a  T h i s e f f e c t might  account  201  for  the  large  amount  of  genotype-environment  interaction  observed  in  my  i n salmonids has been d i s c u s s e d  by  results.  The Leary  inheritance of meristic  et  a l . (1985)  heritabilities that  and  variation  Lindsey  for meristic  traits  much p h e n o t y p i c v a r i a t i o n  heterozygosity Swain  Leary  i n rainbow  in meristic  argued  that  measured a g a i n s t  variability  heterozygosity  because  complex  for  The  any  incubation  description  spring wild  counts  regime  incubation  caught  incubation suggests  o f AB  except  by  that  the  genome o f  the  vertebral  count  the  degree  characters could  idea e m p i r i c a l l y  of  not  be  traits.  with chum  developmental s t a b i l i t y  regime  a  quantitative  (1981) (Lindsey  f r y reared  were s i m i l a r  under  t o counts o f W  the  count  differed  and  such  from  o f WB  f r y reared  the  f r y reared other  i n the w i l d  -  winter  under  under  distribution.  It further  suggests  of  -  spring  the winter  -  i n the  the w i n t e r -  spring  -  67.50).  incubation  to e x p l a i n that  the  As  p o p u l a t i o n s (X  is sufficient  as  1988).  autumn  i n t e r a c t i o n .between the temperature  population  model  (X = 65.80 and X - 65.60, r e s p e c t i v e l y ) .  fry, vertebral regime  from  idea  response o f the genome t o environmental change seems too  " A t r o p o s i c Model" o f L i n d s e y and Arnason  Vertebral  high  invoked the  these were t h r e s h o l d  between m e r i s t i c  heterozygosity.  stems  i n meristic  salmon  relationship  They  found  T h i s view has been c h a l l e n g e d by  (1987) t e s t e d t h i s  found no  a l . (1985)  trout.  Furthermore, Beacham and W i t h l e r and  et  traits  and developmental s t a b i l i t y .  (1987) who  properly  (1988).  the AB  This and  the  the  observed  and  W stocks  202  are adapted t o compensate e f f e c t i v e l y w i l d so as t o produce  Judged  from  the same  the  percentage  between  wild  when  a l l temperatures  within  lab populations  variation  were  environmental  variance contributes  temperature  regime  separation  was  contributes  to genetic  greatest and  that  cover  a  much  a  range  with  the  divergence  single  of  The  range  four  hypothesis  between  because  Yet the d i r e c t i o n  that  had the g r e a t e s t  the  regimes.  variability  temporal  the p o p u l a t i o n s .  between s t o c k s i n the w i l d which  phenotypic  temperature  environmental  of  between the  of  temperature  i n the w i l d .  among  degree  the m i s c l a s s i f i c a t i o n  more with  i s g r e a t e r than  consistent  was g r e a t e r than  pooled.  with  the  in of  isolation  Separation  was  s e p a r a t i o n i n time  space.  The the  pattern o f morphological d i f f e r e n c e s  alteration  1979,  Gould  o f the t i m i n g  1982).  Slatkin  and environmental v a r i a t i o n of  than  temperatures  fish  (and hence  was  pooled  misclassifications,  reared  populations)  The  of  the l a b o r a t o r y  greater  o f i n c u b a t i o n i n the  phenotype.  separation even  f o r the temperature  ontogenetic  developmental traits.  developmental  Selection events.  i n development  a model t h a t  links  (Balon genetic  t o both the r a t e s o f t i s s u e growth and the t i m i n g The  governs  can t h e r e f o r e Heterochrony  model  shows  variation  S e l e c t i o n on the phenotype  parameters.  or p r o c e s s e s  (1987) has developed  transitions.  parameters  o f events  among the s t o c k s may be due t o  and  how  genetic  covariation  variation in  in  phenotypic  a l t e r s the d i s t r i b u t i o n s o f developmental lead  t o changes  i n the average  i s most e v i d e n t i n comparisons  times o f  between AB  203  progeny  and  W  progeny.  At  a l l temperatures  l a r g e r eyes, l o n g e r snouts and p e c t o r a l f i n s . and  deeper  heads than  the W progeny.  of  incubation  the  AB  f r y had  They a l s o tended to have l o n g e r  In o t h e r c h a r a c t e r i s t i c s ,  such as  the  number o f p a r r marks, weight and body depth, whose e x p r e s s i o n depended l e s s on skeletal  development,  consistent. deeper  bodies  lighter the  At 6 C  and  than  had  direction  the AB the  W  progeny  progeny.  of were  interstock  differences  h e a v i e r with  Under  the  fewer  parr  less  marks  progeny  and  regime  AB  The  timing  o f emergence  a c c e l e r a t e d r e l a t i v e t o the r a t e o f development  f i n s and  was  early  s h a l l o w e r b o d i e s compared t o W.  W progeny was  snout, p e c t o r a l  the  were of  o f the eyes,  head.  The evidence p r e s e n t e d here I b e l i e v e demonstrates c o n c l u s i v e l y t h a t when reared  under  the  same  environmental  reproduce d u r i n g d i f f e r e n t is  most  striking  morphology. problems,  for  d u r i n g the embryonic strong Also, of  in  the  incubation  that  duration the  period.  that,  has  effects  of  1982-83  there  post-emergent,  i t i s clear  temperature of  the  populations that  seasons are g e n e t i c a l l y d i f f e r e n t .  Discounting i t appears  conditions  the  incubation  experiment,  is little  period  by  difference  and of  external technical  temperature  regime  Rather the r e s u l t s suggest t h a t s e l e c t i o n may migrant  phase  f o r a l l the q u a n t i t a t i v e  traits  a profound  This  because  selection  naturally  downstream  effect  on  phenotype.  of  the  studied,  In s p i t e  of  life  be  cycle.  temperature this,  when  are removed, the p o p u l a t i o n s show a p p r o p r i a t e a d a p t a t i o n  t h e i r q u a n t i t a t i v e t r a i t s t o season o f r e p r o d u c t i o n .  204  EVIDENCE FOR SELECTION ON INCUBATION RATE  INTRODUCTION  According be  t o e v o l u t i o n a r y theory  partitioned into  (Falconer  1981).  evolution  under  genetic The  and  reason  natural  be s e l e c t i v e l y  selection  or non  distinction  depends  According  maintained  variance  environmental  for this  c e r t a i n components o f v a r i a n c e . may  phenotypic  on  the  to B u l l  i n a population  of a population heritable  i s that relative  components  the r a t e  of  magnitudes o f  (1987) phenotypic  according  may  variation  t o i t s components:  s e l e c t i o n may favor the maintenance o f o n l y t h e environmental components, o n l y the g e n e t i c components, or be i n d i f f e r e n t  t o the composition  Even when s e l e c t i o n i s shown t o f a v o r phenotypic components, the p o s s i b i l i t y  variation  o f the v a r i a n c e . regardless of i t s  e x i s t s t h a t environmental v a r i a n c e  d i s p l a c e g e n e t i c components or v i c e v e r s a .  will  Environmental and g e n e t i c f a c t o r s  may thus compete t o produce a g i v e n s e l e c t e d l e v e l o f phenotypic  I time  have  has  distinct fitness  hypothesized  caused  incubation  related  traits  to  Therefore,  i f the r a t e  natural  a  fixed  natural rate  spawning p o p u l a t i o n s  selection  through  that  generally optimum  one  would  to  evolve  According  the  additive  o f each p o p u l a t i o n expect  the  among  emergence seasonally  to Falconer  low h e r i t a b i l i t i e s  removes  of incubation  selection  salmon.  have  variance.  s e l e c t i o n f o r synchronized  differences  o f chum  evolve t o  because  (1981) constant  genetic  variance.  has been  determined  heritability  to  be  low.  205  However, related  relatively traits  high  have  estimates  been  recently  of additive recorded  genetic  variance  i n aquatic  in  organisms  fitness (Gjedrem  1983).  MATERIALS AND METHODS  To e s t i m a t e the c o n t r i b u t i o n o f maternal time  to  hatch  and  f a m i l i e s produced  emergence  within  The s i r e ,  dam and s i r e  for  to  and  (Falconer  hatch  of  factorial  method d e s c r i b e d by Becker  similar  estimates  by  the  25  at 8 C d u r i n g  at 8 C were  correlation  between  estimated relatives  were  from i n d i v i d u a l f a m i l y r e a r i n g s by  (1975).  generated  The lower by  t o t h a t o f Rodda e t a l . (1977).  e n t e r e d when I gathered  the d a t a  the e s t i m a t e s o f hatch time normally  t o emergence  from  individually  heritabilies  e s t i m a t e s were c a l c u l a t e d  the h e r i t a b i l i t y  technique  time  p l u s dam  reared  samples  1981).  Heritability the  populations  per p o p u l a t i o n were a l s o  1983-84. time  the  and a d d i t i v e g e n e t i c v a r i a n c e t o  distributed.  emergence  time  offspring  generated  f o r hatch  per  Carlo  simulation  I assumed t h a t  and emergence t i m e .  limit  the e r r o r  The e r r o r i n  and emergence time o f each f a m i l y I assumed to be  200 h e r i t a b i l i t y  o f each  a Monte  confidence  sub-population family.  The  e s t i m a t e s were computed f o r hatch and from  simulated  tenth  e s t i m a t e was taken as the lower c o n f i d e n c e  lowest  limit.  random  samples  simulated  o f 100  heritability  206  RESULTS  F a m i l i e s where m o r t a l i t y exceeded 10 per cent heritability the  f o r time t o hatch and time t o emergence.  possibility  ontogeny cells  and  suggested  by  mortality could  i n the a n a l y s i s  maintain  a factorial  of AB was reduced  I  Estimated  design.  t o 4x4; WB,  f o r WB  heritability -  W).  than  sire  Allendorf be  chose  was 4x4 f o r AB; 2x5 f o r WB;  0.35  were not used  linked. to  drop  The s i r e  dam h e r i t a b i l i t y .  rows  than  and  that  developmental  contend  columns  (SxD) d e s i g n  as  with  missing  necessary  f o r time  to  t o hatch  The SxD d e s i g n f o r time to emerge  3x4 f o r W.  f o r W.  f o r time t o hatch  In a l l cases,  Rather  4x3;, W, 3x4.  I d i d t h i s to eliminate  a l . (1983)  by dam  p l u s dam h e r i t a b i l i t y  and 0.47  et  t o estimate  except  f o r time  Heritability  f o r time  i n a l l populations emergence o f AB,  The lower  to hatch  t o emerge  0.27  f o r AB,  exceeded the  (0.50 - AB, 0.40 - WB,  sire  confidence l i m i t s  were g r e a t e r than zero i n a l l cases  was  heritability estimated  was  0.54  greater  v i a simulations  ( T a b l e s 57 and 5 8 ) .  DISCUSSION  Heritability 1981). to  estimates  Thus, a p p l i c a t i o n  discussions of genetic  with c a u t i o n .  may  vary  depending  of h e r i t a b i l i t y variation  on  estimates  the from  environment  (Hartl  laboratory rearings  i n natural populations  must  be t r e a t e d  207  T a b l e 57. H e r i t a b i l i t i e s and l o w e r c o n f i d e n c e l i m i t t i m e t o 50 % h a t c h a t 8 C.  ( L C L ) (P =  0.05) f o r  Heritability Sire Population  Dam  S i r e Plus Dam  Mean  LCL  Mean  LCL  * Mean  LCL  AB  0.38  0.250  0.16  0.066  0.27  0.203  WB  0.71  0.524  0.14  0.025  0.35  0.214  W  0.77  0.629  0.64  0.115  0.47  0.388  T a b l e 58. H e r i t a b i l i t i e s and l o w e r c o n f i d e n c e l i m i t (LCL) (P = 0.05) f o r t i m e t o 50 % emergence a t 8 C. Heritability Sire Population  Dam  S i r e Plus Dam  Mean  LCL  Mean  LCL  Mean  LCL  AB  0.44  0.330  0.56  0.452  0.50  0.431  WB  0.73  0.684  0.10  0.047  0.40  0.377  W  0.93  0.807  0.52  0.101  0.54  0.474  208  Maternal differences  e f f e c t s appear t o be r e l a t i v e l y unimportant to w i t h i n i n time  to hatch  and time  t o emergence.  This  population  suggests  that  i n c u b a t i o n r a t e i s c o n t r o l l e d d i r e c t l y by the genome.  The  relatively  individual predict = fast  high  variation  heritabilities  i n incubation  suggest  from a r i g i d model o f e a r l y stock  mixing  selection.  o f genes  for fast  within population genetic  The  relatively  slight  shifts  high  Gene  flow  = slow i n c u b a t i o n  and slow  between  greater  than one might  rate  : late  stock  genetic  variation  i n the optimum  time  higher  s u r v i v a l while  genetic  recombination  years  thereby  could  even when cause the  increasing the  slightly  variation  s i n c e each year  (1975) suggested  a population  o f downstream faster  the s i t u a t i o n  o f the p o p u l a t i o n  additive genetic  rates  within  would  incubation  not come years  result In some  r a t e s have  may be r e v e r s e d .  The l a c k  means t h a t t h e  to e q u i l i b r i u m .  would l i k e l y  The  be a f a i r l y  s e v e r a l ages o f chum salmon spawn t o g e t h e r .  an a l t e r n a t i v e e x p l a n a t i o n  variance  could  emergence.  i n the environment  between animals born i n d i f f e r e n t  common occurrence  Lande  i n other  due t o annual  composition  remain high  variability.  t h e progeny o f i n d i v i d u a l s with  of p r e d i c t a b i l i t y  could  the p o p u l a t i o n s  incubation  years,  high  i s much  incubation rate.  strong  from  there  r a t e w i t h i n each p o p u l a t i o n  There a r e s e v e r a l ways whereby h e r i t a b i l i t y under  that  i n selected t r a i t s .  f o r the presence o f  He demonstrated t h a t the  209  high  spontaneous  hundred  mutation  gametes) c o u l d  strong s e l e c t i o n . thousands o f could  be  maintain  young per  fish  quantitative  heritable  For  example,  characters  variation  even  chum salmon with the  a substantial from a  female with  a  i n c r e a s e i n the  return  the  variation  Essentially,  fitness  related  Disruptive incubation are  variation. traits  so  equally  on  that  an  one  genetic  characteristics  selection rate  so  favored.  could  that  at  might  genetically interact  equilibrium  be  each of  of  to produce generation 2000 eggs trait.  quantitative  may  If  trait  a l s o prevent  genes may  fitness  in  and  maintained  the  range o f  one  for  two  trait  is  Thus,  disruptive  incubation  stabilizing and  the  i s constrained.  through  with  hatch  code  vice versa.  in either t r a i t  correlated  with a  in  other t r a i t  genetic variation  variability  gene or  increase  a decrease i n f i t n e s s i n the  e f f e c t s o f s e l e c t i o n on  Finally,  one  population.  genetic  accompanied by  per  presence  potential  i n the  of  selection  one  the  fecundity  among f i t n e s s r e l a t e d t r a i t s  the  in  number o f o f f s p r i n g  Antagonistic plieotropy loss  (  f r y should have a mutation f o r a p a r t i c u l a r q u a n t i t a t i v e  these mutants mate t o g e t h e r on will  of  In a s p e c i e s l i k e  mutants.  roughly 20  rate  rate.  selection emergence  on  times  210  An E l e c t r o p h o r e t i c A n a l y s i s o f Genetic V a r i a t i o n among S e a s o n a l l y Separated  Populations  211  INTRODUCTION  A  considerable  physiological, factors  portion  behavioural  (Falconer  on  1981).  analyses  1981).  In  some  genetic  control  cases of  Recently experiments  in  the  for  the  and  experiments  1981, of  refer  relative,  and  classical  techniques  than  to  distinct  interpreting  the  to  i s determined by  evolutionary  characteristics  have  been  traits  literature  and,  estimation  made  that  are  as  by  nongenetic  relationships  (Ryman  and  or  based Stahl,  over-emphasizing  also  described  environmental  characters  Naevdal e t a l . 1978,  workers  particular  absolute, of  of  important  Smoker 1982).  estimates  morphological,  influenced  by  the the  S t a h l 1981).  other  not  phenotypic  conclusions  Gjedrem 1978,  Leggett,  of  of  d i s t r i b u t i o n o f g e n e t i c v a r i a t i o n cannot be  of  components o f e c o l o g i c a l l y Gunnes and  variability  Assessment  phenotypic  environment (Ryman and  the  or m e r i s t i c c h a r a c t e r s  e s t i m a t i o n o f the amount and exclusively  of  results  and  to  a  at of  particular  and  4,  detailed  genetic  variance  R e f s t i e and  S t i e n 1978,  extent  conditions  in and  section they  1976,  Riddell  emphasized, however, t h a t  experimental  breeding  section  have been made (Gjedrem  lesser  measure o f the  animal  allelles  I t must be  in  i n the 4  such  constitute  amount of g e n e t i c v a r i a t i o n .  refer loci.  quantitative  to  "statistical" One  genetic  must  genes  The  rather  consider  this  when  information  for  the  d i s c r i m i n a t i o n o f s t o c k s or assessment o f e v o l u t i o n a r y r e l a t i o n s h i p s .  212  Electrophoretic specific at  genetic  single loci  techniques  can  relationships.  confirmed the  in s e v e r a l s p e c i e s eg.  allow  Early  existence  A t l a n t i c cod  a  detailed  electrophoretic  recently  demonstrated Atlantic  the  detailed  herring  (Anderson et  trout  (Allendorf  et  spp.)  (Vuorinen et a l . 1981).  Electrophoresis populations.  has  Firstly,  many it  f o r the  Pacific  B.C.,  personal  clear  quantitative  unbiased  Ryman  is  (Roughgarden 1979, point  answers. of  the  because,  at  best,  large  a l . 1979),  The  easy  to  number of  and  a  Hubby 1966,  for  genetic  perform  miss even some of  these.  such  as  (Coregonus  analysis  and  (CC.  most  of  of the  Wood, D.F.O., Nanaimo,  of  they Harris  isozymes are  is  neutral  1966).  detects  generally  only  be  gives  considered to  an  selection  However, t h i s  last  underestimated  those  s u b s t i t u i o n s t h a t r e s u l t i n charge d i f f e r e n c e s i n a p r o t e i n , and may  have  1981), brown  Whitefish  amount of polymorphism may  electrophoresis  loci  species  (Stahl  electrophoresis  sample  because  of  a r e g u l a r p a r t o f the management  fisheries  Secondly,  Third,  Lewontin and  routine  a  of populations  I t i s now  salmon  genome  i s open t o q u e s t i o n .  et  relatively  Coast  of v a r i a t i o n  A r t i e char (Nyman 1972).  attractive properties  communication).  sample  on  structure  t e c h n i q u e s have been s t a n d a r d i z e d . strategy  based  and  a l . 1981), A t l a n t i c salmon  a l . 1977;  intra  (Gadus morhua) (Frydenberg e t . a l . 1965),  studies  complex g e n e t i c  analyses  of  of g e n e t i c a l l y d i f f e r e n t i a t e d s u b u n i t s  A t l a n t i c salmon (Salmo s a l a r ) (Payne et a l . 1971)  More  examination  amino  the  acid  procedure  213  For in  the  example, a change  number  Drosophila  of  also  identified  pseudo  heterozygosity  are  fluids.  Such  obscura  from 0.44  over-estimate  surveyed  i n technique  those  the  an  0.73  (Singh  are  often  transformation.  enzymes, a l s o , they  The  total  and  electrophoretic  studies  populations  an  Within reviews (1979). Group  II  of  the the  and  may  II  locus  of  37 in  average  Electrophoresis could the  concentration  enzymes  typically  i n t i s s u e s or  body  II enzymes to d i s t i n g u i s h them  enzymes  do  i n processes  not  include  such  as  regulatory  by  have suggested  decoupled  give  some  of of  a l l enzymes may  that molecular  (Clayton  insight  mutation, phenotypic  into  be l e s s than  1981). the  genetic  drift,  variation  evolution  Thus,  genetic and  provides  1%  while  history  of  migration, information  f o r c e s as w e l l .  usage  one,  are  analysis  Salmonidae,  I assayed  estimate  I enzymes i n v o l v e d  Group  environment  genetic  regarding s e l e c t i v e  the  because  Group  from 6 to  dehydrogenase  a l . 1976).  high  called  some authors  evolution  in  in  increase  are not an adequate sample o f the genome.  Finally,  organismal  quantitative  et  sample o f genes r e p r e s e n t e d  o f the genome.  xanthine  polymorphism  Group  Since  the  increase  in r e l a t i v e l y  from more s u b s t r a t e - s p e c i f i c energy  at  and  amount o f  found  enzymes  to  alleles  r e s u l t e d . i n an  refer  e l e c t r o p h o r e s i s has to W i t h l e r  a wide a r r a y PGM-1, which  ( A l l e n d o r f e t a l . 1983).  et  been  used  a l . (1982) and  extensively. A l l e n d o r f and  o f enzymes, some o f which are has  been  suggested  as  a  Group  regulatory  For Utter  I, some enzyme  214  However,  I do not imply  sample  f o r that  chapter  I will  would  among  differentation direction and  the l o c i  perfect  compare h e t e r o z y g o s i t y  t e s t whether the l o c i migration  require  that  here  are a  representative  knowledge o f a l l systems. at each  population;  a r e i n Hardy-Wienberg e q u i l i b r i u m ; e s t i m a t e  the g e n e t i c  populations;  among the p o p u l a t i o n s ; migration  locus  determine  within  In t h i s  each  the  of genetic  used  the  amount  of  determine e f f e c t i v e p o p u l a t i o n  among  the populations;  genetic  genetic s i z e ; the  similarities;  c o n s t r u c t a Wagner Tree o f r e l a t e d n e s s among the p o p u l a t i o n s .  MATERIALS AND METHODS  Samples from  spawning a d u l t s  transported was  o f hypaxial  done  i n the winter  procedure  The  (Table  of  and eye t i s s u e  were  1 ) . F i f t e e n o f these  "100".  Tissue  Other  samples  electrophoresed  by A l l e n d o r f and U t t e r  most common a l l e l e  travelled  1983-84.  The supernatants  described  designated  liver  were  t h e 1981, 1982, and 1983 seasons.  r e s u l t s from t h e remaining  The  they  during  heart,  t o the l a b o r a t o r y on i c e and s t o r e d a t - 20 C u n t i l  centrifuged.  screened  muscle,  using  (1979).  A total  were  collected  Tissues  were  the a n a l y s i s ground  and  the starch g e l o f 39 l o c i  were monomorphic or d i d not s t a i n  were well.  24 enzymes were used f o r computations.  (see s t u d i e s by Beacham  alleles  were  i n the g e l r e l a t i v e  designated  i n L i t e r a t u r e c i t e d ) was  according  t o the d i s t a n c e  to the distance  travelled  by t h e most  215  T a b l e 59. electrophoretic  Enzymes w i t h i n analysis.  tissues  and b u f f e r  BUFFER  systems  used  in  USED IN ANALYSIS  TISSUE  ENZYME  Muscle Muscle Muscle Muscle Muscle Muscle Muscle Muscle Muscle Muscle Muscle Muscle Muscle  IDH-1,2 ME-1 LDH-1,2 LDH-3,4 LGG-1 AGP-1 MDH-3,4 6-PG PGI-1 PGI-2 PGI-3 PGM-1 GL-1  AC AC RW RW RW AC AC AC RW RW RW RW RW  YES YES YES YES YES NO NO NO NO NO YES NO NO  Heart Heart Heart Heart Heart Heart Heart  IDH-2 AAT-1,2 MDH-1,2 MDH-3,4 PMI AGP-1,2 ACON-1,2  AC AC AC AC AC AC AC  YES YES NO YES YES YES NO  Heart Heart Heart Heart Heart  ACON-3,4 LDH-3 PGM-1 GL-1 LGG-1  AC MF AC MF MF  NO YES NO YES YES  Liver Liver Liver Liver Liver Liver  IDH-3,4 MDH-1,2 PGM-1 LDH-4 PMI SDH  AC AC AC RW AC RW  YES YES YES YES NO YES  Eye Eye Eye Eye Eye Eye Eye Eye  IDH-3,4 AAT-3 MDH-1,2 MDH-3,4 GAP LDH-5 GL-2 LGG-1  AC AC AC AC AC MF MF MF  YES YES NO YES NO NO YES YES  the  216  common  allele.  F o r example,  travelled  by  travelled  twice  designated  as "200".  Average within sampled  the most  the d i s t a n c e  heterozygosity  each  population  that  Hardy-Weinberg system  common  are  i f an allele  the  i t was  designated  as  "50".  If i t  common  allele  i t was  by  actually  ways:  the most  (for2 allele  (2)  (Nei 1978).  test  the  hypothesis  (3) the unbiased  that  each  e q u i l i b r i u m at each l o c u s a c h i - s q u a r e observed  equilibrium. frequencies  2pq, f o r a 4  genotype The  frequencies  chi-square  on  allele  allele  Pooling  in  Hardy-Weinberg  and those  test  expected  i s suspect Therefore,  in  under cases  using  Hardy-Weinberg where  when more than  expected  two a l l e l e s  u s i n g t h e genotypes pooled  into  i s accomplished by c o n s i d e r i n g a l l a l l e l e s except t h e  as a s i n g l e  allele.  Three  homozygotes f o r the most common a l l e l e ; and one o f t h e other  r e s u l t i n g chi-square  is  o f H based on  g o o d n e s s - o f - f i t t e s t was employed  o f some c l a s s e s a r e low.  three c l a s s e s .  estimate  population  were observed a t a l o c u s , t h e t e s t i s repeated  allele  =  based  H = 2pq + 2pr + 2ps + 2qr -•- 2qs + 2 r s where p, q, r , and s a r e t h e  conditional expectations  common  H  loci  of individuals  heterozygosity  system  distance  o f the polymorphic  (1) t h e p r o p o r t i o n  heterozygous;  alleles);  the  half  was c a l c u l a t e d f o r each  frequencies o f d i f f e r e n t  To  travelled  travelled  i n three  expectations  allele  value  alleles;  classes  o f genotype  (2) h e t e r o z y g o t e s and  result:  (1 )  f o r the most common  (3) a l l o t h e r  genotypes.  i s used with one degree o f freedom.  The  217  The Rate o f M i g r a t i o n a t E q u i l i b r i u m  Assuming the p o p u l a t i o n s are at e q u i l i b r i u m with r e s p e c t t o m i g r a t i o n and that s e l e c t i o n drawn a l l e l e the  and mutation are n e g l i g i b l e  the p r o b a b i l i t y ,  m, t h a t a randomly  i s from a migrant depends on the degree o f d i f f e r e n t i a t i o n  populations,  F  s t >  a n c  j  the e f f e c t i v e  population  size,  N,  among  i s as f o l l o w s :  2 F  =  (1/2N - (1 - 1/2N) x F  ST  ) (1 - m)  ST  Thus m can be e s t i m a t e d a s : F m  0.5  1 1/2N + (1 - 1/2N) x F  Calculation  of Effective  Population Size  I used t h r e e d i f f e r e n t  measures  was simply t h e mean p o p u l a t i o n s i z e collected  (1981-1983).  of effective  population s i z e .  from the t h r e e years  The f i r s t  i n which samples were  218  N  81  +  N82 +  N83  Ne  As a more r e l i a b l e e s t i m a t e sizes size  recorded from year  from  I c a l c u l a t e d the harmonic mean o f the p o p u l a t i o n  1981-1985.  t o year  I assumed  during  this  that  the f l u c t u a t i o n  i n population  p e r i o d would approximate the f l u c t u a t i o n s  from g e n e r a t i o n t o g e n e r a t i o n .  1  1  N  For  the f i n a l  generations  1  5  e  estimate  to be 3 years  N81  I  1  1  1  1  N82  N83  N84  N85  assumed  that  the average  and c a l c u l a t e d the e f f e c t i v e p o p u l a t i o n s i z e  harmonic mean o f t h e p o p u l a t i o n s i z e s o f 1981 and 1984.  1  N  1  e  interval  1  2  1  N81  N84  The sex r a t i o was assumed t o be 1:1 i n the p o p u l a t i o n .  between as the  219  DIRECTION OF MIGRATION  The  pattern  individual the to  loci  stocks. W,  may  the  be  populations of  used  to i n f e r  monomorphism  the most l i k e l y  Six pathways e x i s t : Gene flow may  W t o AB,  analysis  among  I  WB  t o W and W t o WB  assume t h a t  be  contributions  from o t h e r s t o c k s are n e g l i g i b l e .  of  exchange  migratory  exchange  (  that  v a r i o u s degrees locus  is  from  of p a r t i a l in  'B' w i l l  population  result  in  remain 'A .  f i x e d i n WB  fixed  in  or  three  migration  complete 'A'  polymorphic  'A'  becoming  in  polymorphic i n both AB and WB  in  AB,  other  ranging  WB  to AB,  AB  of  this  s t o c k s or  that  in  from  population  reverse d i r e c t i o n  example,  polymorphic  in  and  'B'  then  eventually if  straying  t h a t are  polymorphic  W  If a  o f migrants  will  t h e r e s h o u l d not be l o c i i n AB,  through  populations.  even with the i n t r o d u c t i o n  For  complete  directions)  o f the  polymorphic  and polymorphic i n W or f i x e d  polymorphic  from  a l l six  polymorphic.  t o W and W t o WB  at  There are 64 p o s s i b l e models  isolation  and  to WB,  For the purpose  populations  M i g r a t i o n i n the  1  o c c u r r e d o n l y from WB i n AB,  and  population  population  W  these  i s , significant  fixed  population  among  from AB  isolated  polymorphism  m i g r a t i o n paths between  (See F i g u r e 25).  these s t o c k s are  and  fixed  fixed  i n WB in  WB  and or  and f i x e d i n W.  GENETIC DISTANCE  Nei data  (1971) developed  for estimating  time between c l o s e l y  the  a statistical  method  number o f codon  related  species.  for u t i l i z i n g  differences  per  electrophoretic  gene and  T h i s method i s u s e f u l  divergence  f o r the study o f  Migration Paths B e t w e e n Bush a n d W a l k e r C r e e k s  Figure 26.  Pathways for gene flow among AB, WB,  and W.  221  gene d i f f e r e n c e s between races species  (Nei 1972).  populations  to  Nei  take  (1971)  into  populations.  This  differences  per l o c u s ,  or c l o s e l y defined  account  statistic which  related was  related local  now  the to  populations  the normalized effect the  called  of  identity  between  polymorphism  accumulated  genetic  within a  number  distance  within of  (D).  gene D has  several useful properties:  (1)  I t i s r e l a t e d t o M a l e c o t ' s c o e f f i c i e n t o f k i n s h i p i n a simple  (2)  I t measures the accumulated number o f gene s u b s t i t u t i o n s per l o c u s ;  (3)  I f the r a t e o f gene s u b s t i t u a t i o n s per year related to evolutionary  (4)  In some m i g r a t i o n or  i s constant  simplest  distance  time;  models i t i s l i n e a r l y  r e l a t e d to geographical  (Wright  measure  of distance  1978) which  i s half  for a the sum  single  This takes  locus  distance  (D •= 0.5  the value o f 1.0 i n t h e case o f two p o p u l a t i o n s  are f i x e d .  f o r the s e p a r a t e  The loci  index  of multiple  (Wright  1978).  i s the P r e v o s t i  o f the a b s o l u t e  between t h e a l l e l i c f r e q u e n c i e s o f the two p o p u l a t i o n s ,  these  i t is linearly  area.  The  allelles  way;  loci  differences Qx - qy .  i n which  different  i s the a r i t h m e t i c mean o f  222  The  concept  means o f  genetic  distance  q u a n t i t a t i v e l y varying  requires  that  a l l of  hyperspace with populations their  of  an  axis  i s the  by  (1926)  generalized  characters.  root  of the  extended  co-efficient took  using o b l i q u e l y i n c l i n e d  of  account  = [0.5 £ k  X  for  distance  multiple loci  D  2D2]£.  with  loci =  This  gives  f r e q u e n c i e s are  differs  frequencies  o f the  The  of  distances  in a Euclidian  distance  between  two  squared d i f f e r e n c e s between  Pythagorean racial  of  theorem.  likeness.  An  example  Mahalanobis  c o r r e l a t i o n s among  the  is  (1936)  characters  by  y  to  a  locus,  and  defined  a r i t h m e t i c average o f the Wright less  (1978) suggests  weight  from  and  to  loci  distance  co-efficients a  modification  i n which  the  with  respect  f o r the of  Dt  difference in  Edwards (1967) proposed a measure of g e n e t i c  Roger's  D  in  >v/q (i) a n d - \ / q y ( i )  the p o p u l a t i o n  l o c a t e d at p o i n t s  variable.  sum  set  the  to  separate =  C/L) allelic  small.  Cavalli-Sforza which  consistant  with  formula:  x  £D.  (£)  A  i n connection  (q (i) - q (i))2]0.5  respect  as the  used  axes.  Rogers (1972) proposed the  D( y)  be  f o r each chosen  the  distance  first  subpopulations  square  coordinates  Pearson's  the  was  x  i n s t e a d o f the  taking  the  square  as the c o o r d i n a t e s  frequencies  roots  of  o f the p o i n t s  themselves.  the  distance allelic  representing  223  Any distance,  two  populations  0  , apart.  which  have  no  alleles  i n common  The s c a l e o f are d i s t a n c e s  gene f r e q u e n c i e s by the angular  are at the same  i s transformed  t o that o f  transformation:  D = O/7J- cos-1 (1-2q)  and  thus  is  symmetrically  stretched  near the m i d d l e .  CD r [ 2 / v / ( 2 ) / y  Q  i n which cos  Nei developed  symmetrically  *  (1978) m o d i f i e d by Nei  the  extremes  but  Another measure used i s the c h o r d a l  c  o  s  —K-^/CqxC i )  =  near  condensed distance:  )  • qy(i))'  the measures o f g e n e t i c i d e n t i t y  (1972) t o remove the b i a s e s  resulting  and g e n e t i c from  samples  distance from  a  s m a l l number o f i n d i v i d u a l s .  D i s t a n c e Wagner Procedure:  Farris procedure  (1970, to  1972) developed  construct  a  evolutionary  heterogeneities i n rates o f divergence.  procedure trees  called  with  the D i s t a n c e  minimal  Wagner  sensitivity  to  224  A Wagner Tree f o r a c o l l e c t i o n i s a t r e e with the  set  of  defined  the  is  nodes o f less  s a t i s f y i n g c o n d i t i o n W1  The of  the  tree  phenetic  (A,B)  equal  length  i s defined tree.  according  A  the  the to  c o l l e c t i o n S i s a subset  length  the  of  length  the  Wagner t r e e ,  of  any  other  of as  tree  1972).  described  f o r each element  =  W1,  t r e e ; W2,  or  (Farris  i s assumed to be  between the two  the  than  d i f f e r e n c e between any  The  tree  the  l e n g t h o f a t r e e i s d e f i n e d by  s t a t e , x ( i , A),  D  of OTU's ( o p e r a t i o n a l taxonomic u n i t s )  following properties:  a l l the  below,  S,  two  of  Farris by  (1972) as f o l l o w s .  a well-defined  a set  Each node A  value,  of characters  or  character  indexed by  such nodes i s d e f i n e d to  i .  The  be:  | ( i , A ) - x(i,B) | x  of  a branch o f  a tree  nodes forming the end to be  tree  the  is said  sum  i s defined  as  be  t o the measure d e f i n e d  phenetic  p o i n t s o f the branch.  o f the branch l e n g t h s  to  the  most parsimonius i n the equation  The  length of  over a l l the i f i t has  difference  branches  minimum  the of  length  above.  RESULTS  Allele shown  in  frequencies  Table  60  at  the  (a,b,c,d).  polymorphic Frequencies  loci of  the  within  each  most  common  population allele  are  varied  Table 60a.  Sample s i z e s , and a l l o z y m e f r e q u e n c i e s o f p o l y m o r p h i c l o c i used i n t h e a n a l y s i s .  MUSCLE  IDH-1,2  ME-1  allele  LDH-1,2*  allele  LDH-3,4  allele  LGG-1  allele  PGI-3*  allele  allele Ln  STOCK  N  100  64  N  100  120  N  100 136  N  100  136  N  100  75  N  100  80  AB  158 0.968 0.032  153 0.601 0.399  157 0.5 0.5  158 0.513 0.487  153 0.889 0.111  128 1.000 0.000  WB  81 0.907 0.093  81 0.648 0.352  81 0.5 0.5  81 0.500 0.500  81 0.821 0.179  50 1.000 0.000  W  92 0.995 0.005  90 0.572 0.428  92 0.5 0.5  92 0.500 0.500  85 0.847 0.153  58 0.991 0.009  Table. 60b.  Sample s i z e s , and a l l o z y m e f r e q u e n c i e s o f polymorphic l o c i used i n t h e a n a l y s i s .  HEART  STOCK  N  IDH-1,2  AAT-1,2  allele  allele  100  110  N  100  115  MDH-3,4  PMI  allele  N  100  120  AGP-1,2  allele  N  100  LDH-3  allele  92  N  100  allele  93  N  100  136  AB  148 0.970 0.030  138 0.819 0.181  137 0.007 0.993  127 0.807 0.193  41 0.976 0.024  156 0.997 0.000  WB  76 0.941 0.059  7.6 0.757 0.243  80 0.000 1.000  72 0.840 0.160  5 1.000 0.000  81 0.994 0.006  W  88 0.966 0.034  79 0.823 0.177  89 0.000 1.000  72 0.889 0.111  45 0.856 0.144  90 1.000 0.000  Table 60c.  STOCK  AB .  N  Sample sizes, and allozyme frequencies of polymorphic loci used in the analysis.  100  80  N  100  75  N  100  27  40  83  N  100  200  N  100  110  N  100  136  120 0.983 0.017  153 0.886 0.114  85 0.682 0.035 0.176 0.106  153 0.931 0.069  1 1.000 0.000  103 0.927 0.073  WB  73 1.000 0.000  810.9010.099  48 0.563 0.063 0.135 0.240  80 0.8810.119  6 1.000 0.000  80 0.994 0.006  W  87 1.000 0.000  89 0.876 0.124  56 0.393.0.036 0.429 0.143  91 0.775 0.225  21 0.905 0.095  91 0.956 0.044  Table 60d.  Sample s i z e s , and aHozyme frequencies o f polymorphic l o c i used i n the analysis.  LIVER  EVE  SDH*  allele  IDH-3,4  AAT-3  ICH-3,4  GL-2*  allele  allele  allele  allele  LGC-1  allele ho  00 STOCK N  AB  100  90  80  22 0.500 0.500 0.00  N  100  27  40  83  N  100  115  N  100  120  N  100  80  N  100  75  123 0.402 0.020 0.492 0.085  120 0.837 0.162  1 0.000 1.000  152 0.987 0.013  1 20 0.946 0.054  WB  3 0.500 0.500 0.000  63 0.452 0.032 0.397 0.119  74 0.932 0.068  20 0.000 1.000  77 1.000 0.000  62 0.903 0.097  W  11 0.500 0.455 0.045  74 0.324 0.014 0.595 0.068  80 0.781 0.219  38 0.000 1.000  89 1.000 0.000  69 0.957 0.043  229  from  fixation  t o 0.429  i n the m u l t i - a l l e l i c  IDH-3,4 l o c u s expressed  in liver  t i s s u e of Walker Creek spawners.  The percentage o f polymorphic l o c i had  the h i g h e s t  percentage  (43.59 ?o ) and W ( 48.72 % ) .  was s i m i l a r among the p o p u l a t i o n s .  o f polymorphic  populations  were s e v e r a l  expressed  liver  were  GL-2 in  i n the muscle  polymorphic  i n the W  i n the other  expressed  for this  60a-d  and  stock  but  i n one  ).  locus.  allele  not  i n heart  locus  o f the  the PGI-3  expressed  i n the WB  i n the h e a r t  tissue  or two  For example,  the PGM-1  expressed  or  i n the  AB  stocks.  tissue,  and the  and W but polymorphic  was  monomorphic  i n W and  two s t o c k s . The AGP-1,2 l o c u s was monomorphic i n WB  and polymorphic i n the o t h e r two s t o c k s . scored  WB  o f W samples.  polymorphism  ( Table  loci  o f the most common  i n the eye were monomorphic i n WB  The LDH-3 l o c u s  polymorphic  showed  tissue  the MDH-3,4 and GL-1  l o c u s expressed  AB.  that  and not the remainder  locus  Similarly,  loci  ) compared to  o f WB samples compared t o 35.89 % o f  o f AB samples and 35.90 % o f the l o c i  There  ( 53.85 %  However, the frequency  was 0.95 or l e s s at 38.46 % o f the l o c i the l o c i  loci  AB  Polymorphism  However, only  might  five  be d e t e c t e d  fish  as more  from WB were individuals  were sampled.  The occur  patterns  i f there  occurred  from  was  o f polymorphism no  the WB  and  interbreeding stock  into  i n the other p o s s i b l e d i r e c t i o n s .  fixation  among  t h e AB  among  the p o p u l a t i o n s  the p o p u l a t i o n s  stock  while  there  or was  could  i f migration no  migration  230  Among 0.30. (  the polymorphic  the average  Mean h e t e r o z y g o s i t y was lowest  For AB, H  standard mean  loci ,  r 0.206 with  ( S.E.  estimates  heterozygosity = 0.046  error  obtained  estimates  ) f o r WB,  from d i r e c t  o f 0.041; For WB, standard  were 0.208  and 0.234  ( S.E. =  ( S.E. = 0.072  less  than  frequencies  H = 0.213  with  e r r o r o f 0.043).  The  ( S.E. = 0.042) f o r AB,  count o f h e t e r o z y g o t e s  ( S.E. = 0.069) f o r AB, 0.277  was  when c a l c u l a t e d from a l l e l e  e r r o r o f 0.044; For W, H = 0.231 with  unbiased  0.218  standard  heterozygosity  0.044  ) f o r W.  The  were h i g h e s t with  0.257  ) f o r WB  and 0.289  ( S.E. -  0.069) f o r W.  Heterozygosity  v a r i e d g r e a t l y from l o c u s to l o c u s  loci  H was very  loci  H might be 1.000 by a d i r e c t  Several  low or near  loci  and LDH-3,4  conform  t o Hardy-Weinberg  i n muscle  population  d i d not conform  GL-1  i n heart  tissue.  ( e.g. LGG-1  count  tissue  SDH  ME-1,  d i d not  i n any o f the p o p u l a t i o n s .  The AB  in liver  i n eye  61).  tissue  t o Hardy-Weinberg  tissue,  At some  whereas i n other  e q u i l i b r i u m (Table  and IDH-3,4  equilibrium  i n eye  61).  ( e.g. LDH i n muscle) (Table 6 1 ) .  were not i n Hardy-Weinberg  LDH-1,2  loci  fixation  ( Table  e q u i l i b r i u m at the MDH-3,4 and  tissue  and GL-2 and AAT-3 i n eye  The W p o p u l a t i o n d i d not conform t o Hardy-Weinberg e q u i l i b r i u m at t h e  IDH-3,4, MDH-1,2, LDH-4 and SDH l o c i  i n the l i v e r  tissue  and the AAT-3 l o c u s  i n the eye.  Loci categories.  that  were Those  not with  in a  Hardy-Weinberg deficiency  of  equilibrium  fell  heterozygotes  into relative  three to  231 Table 61. Heterozygosity and t e s t o f conformance t o Hardy-Weinberg e q u i l i b r i u m o f polymorphic l o c i w i t h i n each population. ( H = Heterzygpsity c a l c u l a t e d uaing Hardy-Weinbecg expectations* HUB = Unbiased Heterozygosity Estimate (Nei 1978); HDC = Proportion o f Heterozygotes; P = P value f o r Chi-Square Test ). POPULATION WB  AB LOCUS  H  HUB  HDC  H  HUB  HDC  H  HUB  HDC  0.061 0.061 0.063 0.681 0.479 0.481 0.078 0.000 0.500 0.502 1.000 0.000 0.500 0.501 0.975 0.000 0.198 0.198 0.209 0.467 0.000 0.000 0.000 1.000  0.168 0.456 0.500 0.500 0.294 0.000  0.169 0.459 0.503 0.503 0.296 0.000  0.185 0.037 1.000 1.000 0.333 0.000  0.358 0.000 0.000 0.000 0.228 1.000  0.011 0.011 0.011 0.958 0.490 0.492 0.011 0.000 0.500 0.503 1.000 0.000 0.500 0.503 1.000 0.000 0.259 0.261 0.282 0.408 0.017 0.017 0.017 0.947  0.059 0.059 0.061 0.297 0.298 0.275 0.014 0.015 0.000 0.311 0.313 0.339 0.048 0.048 0.049 0.006 0.006 0.006 0.033 0.033 0.000 0.203 0.203 0.229  0.111 0.368 0.000 0.268 0.000 0.012 0.000 0.178  0.112 0.371 0.000 0.270 0.000 0.012 0.000 0.179  0.118 0.382 0.000 0.292 0.000 0.012 0.000 0.198  0.583 0.754 1.000 0.462 1.000 0.955 1.000 0.324  0.066 0.292 0.000 0.198 0.247 0.000 0.000 0.217  MUSCLE IDH-1,2 ME-1 LDH-1,2* LDH-3,4 LGG-1 PGI-3* HEART IDH-1,2 AAT-1,2 MDH-3,4 PMI AGP-1,2 LDH-3 GL-1* LGG-1  0.703 0.399 0.000 0.325 0.873 0.968 0.000 0.110  0.066 0.068 0.293 0. 304 0.000 0.000 0.199 0. 194 0.250 0. 289 0.000 0. 000 0.000 0.000 0.218 0. 247  0.741 0.711 1.000 0.895 0.257 1.000 1.000 0.183  LIVER IDH-3,4 MDH-1,2 PGM-1 LDH-4 SDH*  0.491 0.128 0.000 0.135  0.494 0.128 0.000 0.136  1 0.435 0.102 0.111 0.106 0.000 1.000 0.126 0.508  1 0.667 0.720 0.237 0.228 0.000 1.000 0.013 0.955  0.640 0.349 0.172 0.084  0.646 0.351 0.177 0.085  1 0.625 0.018 0.4510.006 0.1900.630 0.022 0.000 2 0.500 0.512 1.000 0.000 0.500 0.600 1.000 0.083 0.541 0.567 1.000 0.012  0.588 0.272 0.000 0.026 0.102  0.591 0.273 0.000 0.026 0.103  0.789 0.000 0.623 0.628 0.841 0.000 0.325 0.034 0.126 0.127 0.135 0.533 0.000 1.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 1.000 0.092 0.248 0.175 0.176 0.194 0.399  0.537 0.342 0.000 0.000 0.083  0.540 0.344 0.000 0.000 0.084  0.604 0.209 0.000 0.012  0.610 0.211 0.000 0.013  EYE IDH-3,4 AAT-3 MDH-3,4 GL-2* LGG-1  0.689 0.030 0.438 0.012 0.000 1.000 0.000 1.000 0.087 0.706  1 Chi-Square Test with Pooling, P = 0.087 for AB, P = 0.486 for WB, P - 0.043 for W. 2 Chi-Square Test with Pooling, P r 0.001 3 Chi-Square Test with Pooling, P = 0.0000 f o r AB, P = 0.003 for WB, P = 0.003 for W.  232 Hardy-Weinberg e x p e c t a t i o n s , those w i t h an excess o f h e t e r o z y g o t e s r e l a t i v e t o Hardy-Weinberg e x p e c t a t i o n s and t h o s e latter that  case  t h e expected  the  deficiency  chi-square  frequency  value  of heterozygotes.  t h a t were n e a r l y monomorphic.  In t h e  o f t h e l e s s common homozygote was so low  was u n u s u a l l y  high.  ME-1  i n muscle  had a  I n c o n t r a s t , LDH-1,2 and LDH-3,4 from muscle,  IDH-3,4 from t h e eye i n a l l p o p u l a t i o n s and SDH from the l i v e r , AAT-3 from t h e eye  i n AB and W, and MDH-12 from l i v e r  heterozygotes. the  heart  t i s s u e from W samples had an excess o f  L o c i c l o s e t o f i x a t i o n i n c l u d e d the MDH-3,4 and GL-1 l o c i  tissue,  t h e GL-2 from t h e eye t i s s u e  from  from t h e samples o f t h e AB  p o p u l a t i o n as w e l l as the LDH-4 from l i v e r t i s s u e from t h e W samples.  O v e r a l l , t h e m a j o r i t y o f the p o l y m o r p h i c heterozygotes 21 polymorphic  than  found  excess o f h e t e r o z y g o t e s  heterozygotes.  i n each p o p u l a t i o n had more  p r e d i c t e d under Hardy-Weinberg c o n d i t i o n s .  loci  o f 17 polymorphic  loci  loci  Twelve o u t o f  i n t h e t i s s u e s sampled from t h e AB spawners had an  r e l a t i v e t o Hardy-Weinberg e x p e c t a t i o n s . found  Sixteen out  i n t i s s u e s from t h e WB spawners had an excess o f  F i f t e e n o u t o f 19 l o c i  showed an excess o f h e t e r o z y g o t e s  in W  samples.  The amount o f g e n e t i c d i f f e r e n t i a t i o n among the p o p u l a t i o n s r e l a t i v e t o a hypothetical overall 62).  group  frequency Three l o c i ,  o f subpopulations,  each homozygous, but h a v i n g  as t h e r e a l p o p u l a t i o n s v a r i e d from l o c u s t o l o c u s h e a r t AGP-1,2, l i v e r  IDH-3,4 and PGM-1, had F ( s t )  t h a t i n d i c a t e d moderate d i f f e r e n t i a t i o n ( Wright F(st)  t h e same  v a l u e s were l e s s than 0.05.  1978,  H a r t l 1980).  (Table values  The o t h e r  The o v e r a l l mean o f 0.016 suggested  that  233  T a b l e 62. Summary o f F - S t a t i s t i c s a t a l l l o c i . TISSUE  LOCUS  F(IS)  F(IT)  F(ST)  MUSCLE MUSCLE MUSCLE MUSCLE MUSCLE MUSCLE  IDH12 ME LDH12 LDH34 LGG-1 PGI-3  -0.080 0.911 -1.000 -0.984 -0.099 -0.009  -0.045 0.912 -1.000 -0.983 -0.092 -0.003  0.032 0.004 0.000 0.000 0.006 0.006  HEART HEART HEART HEART HEART HEART HEART HEART  IDH12 AAT12 MDH34 PMI AGP12 LDH-3 GL LGG-1  -0.047 -0.004 1.000 -0.061 -0.146 -0.005 1.000 -0.128  -0.043 0.001 1.000 -0.052 -0.060 -0.003 1.000 -0.126  0.004 0.006 0.005 0.009 0.075 0.002 0.011 0.001  LIVER LIVER LIVER LIVER LIVER  IDH34 MDH12 PGM-1 LDH-4 SDH  0.005 -0.165 -0.105 0.306 -0.946  0.060 -0.123 -0.033 0.319 -0.943  0.056 0.036 0.066 0.019 0.002  EYE EYE EYE EYE  IDH34 AAT-3 GL-2 LGG  -0.327 -0.213 1.000 -0.032  -0.305 -0.176 1.000 -0.023  0.017 0.031 0.009 0.009  MEAN  -0.265  -0.244  0.016  234  only  a  limited  amount  e l e c t r o p h o r e s i s had  Significant  of  genetic  occurred  differentiation  among the  differences  in  in  loci  eye AAT-3 (Table  allele  frequency  among  within  effective  Table  64)  The  w h i l e the e s t i m a t e s the  method.  the AB.  The  of the  AB  lowest  population  about 6 times  The  migrant was population (Table  for W  was  probability  about  to  using  to 22  the  three  % o f the  methods v a r i e d  combined  average (  varied  least  3.1  %)  were by  the  and  modified  10  the times  a l g e b r a i c mean method harmonic  l a r g e r than  the WB  for  WB,  mean method  for  population  and  the W p o p u l a t i o n .  that  h i g h e s t i n the WB (1.9  estimated  e f f e c t i v e p o p u l a t i o n s i z e o f WB  estimates  l a r g e r than  mean  IDH-3,4, MDH-1,2 and  of W e f f e c t i v e p o p u l a t i o n s i z e were the most depedent upon  harmonic mean method The  sizes  from p l u s or minus 7 %  estimates  populations  MIGRATION RATES  population  populations  the  63).  EFFECTIVE POPULATION SIZES AND  The  by  populations.  o c c u r r e d at 6 l o c i , muscle IDH-1,2, heart AGP-1,2, l i v e r LDH-4 and  detectable  an  allele  population  and  lowest  drawn  (4.1  i n the  at  t o 4.5 AB  random  ? o ) , next  population  will  be  highest (0.38  from  a  i n the W  to 0.45  %)  65).  All unbiased  measures o f g e n e t i c d i s t a n c e or g e n e t i c minimum d i s t a n c e show t h a t AB  and  WB  identity  except  are the c l o s e s t  Nei's  (1978)  in their  enzyme  235  Table 63. Contingency chi-square a n a l y s i s at a l l l o c i . C h i Square probability values a r e f o r the hypothesis that t h e samples drawn from t h e same p o p u l a t i o n .  and were  TISSUE  LOCUS  NO. OF ALLELES  MUSCLE MUSCLE MUSCLE MUSCLE MUSCLE MUSCLE  IDH12 ME-M LDH12 LDH34 LGG-1 PGI-3  2 2 2 2 2 2  18.277 2.089 0.000 0.106 4.417 3.076  2 2 2 2 2 2  0.00011 0.35193. 1.00000 0.94844 0.10985 0.21486  HEART HEART HEART HEART HEART HEART HEART HEART  IDH12 AAT12 MDH34 PMI-H AGP 12 LDH-3 . GL-H LGG-1  2 2 2 2 2 2 2 2  2.380 2.906 2.475 4.532 9.128 1.070 5.372 0.533  2 2 2 2 2 2 2 2  0.30425 0.23391 0.29007 0.10374 0.01042 0.58570 0.06816 0.76618  LIVER LIVER LIVER LIVER LIVER  IDH34 MDH12 PGM-1 LDH-4 SDH-L  4 2 2 2 3  42.329 25.679 1.436 9.529 2.338  6 2 2 2 4  0.00000 0.00000 0.48775 0.00853 0.67392  EYE EYE EYE EYE  IDH34 AAT-3 GL-2LGG-E  4 2 2 2  11.522 13.819 4.396 3.659  6 2 2 2  0.07353 0.00100 0.11102 0.16052  171.065  56  0.00000  (TOTALS)  CHI-SQUARE  D.F.  P  236  Table 64. Estimates of effective population using the algebraic mean, harmonic mean methods d e s c r i b e d i n t h e t e x t .  Population  AB  METHOD 1 A l g e b r a i c Mean  3800  population size f o r each harmonic mean and m o d i f i e d  METHOD 2 Harmonic Mean  METHOD 3 M o d i f i e d Harmonic  4078.14  3416.77  WB  318.33  325.30  355.56  W  775.33  478.36  593.55  237  T a b l e 65. P r o b a b i l i t y t h a t a randomly chosen a l l e l e w i l l be from a m i g r a n t i n d i v i d u a l assuming random m a t i n g , no s e l e c t i o n , o r m u l t a t i o n . (See t e x t f o r d e t a i l s o f c a l c u l a t i o n o f m from F and N ) . EFFECTIVE POPULATION  LOCUS  AB  METHOD 1 WB  W  AB  SIZE CALCULATED BY  METHOD 2 WB  W  AB  METHOD 3 WB  W  Muscle IH-1,2 ME LDH-1,2 LDH-3,4 LGG-1 PGI-3  0.00198 0.01599 1.00000 1.00000 0.01072 0.01072  0.02294 0.15215 1.00000 1.00000 0.10920 0.10920  0.00961 0.07175 1.00000 1.00000 0.04949 0.04949  0.00185 0.01492 1.00000 1.00000 0.01000 0.01000  0.02247 0.14958 1.00000 1.00000 0.10723 0.10723  0.01544 0.10922 1.00000 1.00000 0.07675 0.07675  0.00221 0.01774 1.00000 1.00000 0.01191 0.01191  0.02061 0.13939 1.00000 1.00000 0.09942 0.09942  0.01250 0.09082 1.00000 1.00000 0.06323 0.06323  0.01599 0.01072 0.01284 0.00717 0.00081 0.03130 0.00586  0.15215 0.10920 0.12715 0.07666 0.00955 0.25126 0.06391  0.07175 0.04949 0.05858 0.03372 0.00395 0.13020 0.02779  0.01492 0.01000 0.01198 0.00668 0.00076 0.02925 0.00547  0.14958 0.10723 0.12492 0.07520 0.00935 0.24771 0.06267  0.10922 0.07675 0.09016 0.05301 0.00638 0.18931 0.04392  0.01774 0.01191 0.01425 0.00796 0.00090 0.03463 0.00651  0.13939 0.09942 0.11606 0.06945 0.00856 0.23342 0.05779  0.09082 0.06323 0.07456 0.04338 0.00515 0.16092 0.03585  0.05988 0.00111 0.00176 0.00093 0.00338 0.03130  0.37611 0.01298 0.02039 0.01093 0.03824 0.25126  0.22014 0.00539 0.00852 0.00453 0.01624 0.13020  0.05613 0.00103 0.00164 0.00087 0.00315 0.02925  0.37199 0.01271 0.01997 0.01070 0.03746 0.24771  0.30058 0.00870 0.01371 0.00731 0.02594 0.18931  0.06595, 0.00123 0.00195 0.00103 0.00376 0.03463  0.35515 0.01165 0.01831 0.00980 0.03444 0.23342  0.26310 0.00703 0.01109 0.00591 0.02106 0.16092  0.00378 0.00205 0.00717 0.00717  0.04254 0.02368 0.07666 0.07666  0.01814 0.00993 0.03372 0.03372  0.00353 0.00191 0.00668 0.00668  0.04168 0.02319 0.07520 0.07520  0.02892 0.01595 0.05301 0.05301  0.00420 0.00228 0.00796 0.00796  0.03833 0.02128 0.06945 0.06945  0.02350 0.01291 0.04338 0.04338  Heart IDH-1,2 AAT-1,2 MDH-3,4 PMI AGP-1,2 LDH-3 GL Liver LGG-1 IDH-3,4 MDH-1,2 PGM-1 LDH-4 SDH Eye IDH-3,4 AAT-3 GL LGG  MEAN  0.00402 0.04506 0.01926 0.00375 0.04416 0.03067 0.00447 0.04062 0.02494  238  patterns.  WB  and  (1978) unbiased bias  from  most  similar  Figure  W,  the  l a t e spawning s t o c k s ,  minimum d i s t a n c e , which i s the  sampling  a small  number  of  AB  W  the  while  and  l o c u s comparison using  shows a wide v a r i e t y  AB  shows that  similar  LGG.  AB  and  WB  Heart AGP  were l e a s t  and W were l e a s t s i m i l a r  Figure suggests  28  shows  that  the  Nei's  AB  Nei's for  the  WB  are  (Table  66,  and  populations  (1978) unbiased  of possible r e l a t i o n s h i p s .  u s i n g Muscle IDH-1, 2, ME, 3,  similar.  only measure c o r r e c t e d  individuals, least  least  27).  A l o c u s by  -  are  are the  a  - 1, 2, L i v e r  similar  populations  Walker Creek b e f o r e s p l i t t i n g  Tree in  and  Prevosti  Creek  i n t o an e a r l y  split  identity  W were l e a s t  Eye  and; L i v e r MDH  using  Bush  and  IDH  u s i n g Muscle LGG  using Heart PMI  Wagner  WB  genetic  - 3, 4, Eye  and  Liver  -1,2  CDH  (Table  distance. from  similar  the  AAT -  4,  67).  The  figure  population  and  l a t e spawning  not  conform to the e x p e c t a t i o n s  in  stock.  DISCUSSION  There are s e v e r a l reasons why  l o c i may  Hardy-Weinberg e q u i l i b r i u m .  It i s p o s s i b l e t h a t non-random mating takes  with  in  respect  frequency viability.  at  to a  the locus.  locus  Progeny  question. that  The  differ  sexes in  may  genotype  differ may  in  have  of  place allele  unequal  239  Figure 27. Similairity.  Genetic  similarity  using  Nei's  (1978)  SIMILARITY  6.96  0.95 --H  1  H  0.97 H  +  0.98 H  H  0.99 H  +  1.00 H  +  * AB ****** * *  * WB  ****** ^  +  + 0.95  +  + 0.96  +  + 0.97  +  + 0.98  +  + 0.99  +  + 1.00  Unbiased  Genet  240  T a b l e 66.  G e n e t i c d i s t a n c e and g e n e t i c i d e n t i t y o v e r a l l l o c i , BELOW DIAGONAL: ABOVE DIAGONAL: POPULATION  T a b l e 67.  ROGERS "D" (WRIGHT 1978) NEI (1972) GENETIC IDENTITY 1  2  AB  ******  0.9969  0.9922  WB  0.0497  ******  0.9902  W  0.0785  0.0876  ******  Genetic d i s t a n c e over a l l l o c i . BELOW DIAGONAL: PREVOSTI DISTANCE (WRIGHT,1978) ABOVE DIAGONAL: NEI (1972) GENETIC DISTANCE POPULATION  T a b l e 68.  1  AB  ******  0.0031  0.0078  WB  0.0376  ******  0.0098  W  0.0484  0.0622  ******  Genetic d i s t a n c e over a l l l o c i . BELOW DIAGONAL: CAVALLI-SFORZA & EDWARDS (1967) CHORD DISTANCE ABOVE DIAGONAL: NEI (1978) UNBIASED MINIMUM DISTANCE POPULATION  1  2  3  1  AB  ******  0.0000  0.0043  2  WB  0.0623  ******  0.0036  3  W  0.0871  0.1045  ******  241  Table 69.  Genetic d i s t a n c e over a l l BELOW D I A G O N A L : ABOVE D I A G O N A L : POPULATION  loci.  C A V A L L I - S F O R Z A & EDWARDS ( 1 9 6 7 ) NEI ( 1 9 7 2 ) MINIMUM DISTANCE 1  2  ARC  DISTANCE  3  1  AB  ******  0.0025  0.0062  2  WB  0.0622  ******  0.0077  3  W  0.0869  0.1042  ******  T a b l e 70.  Genetic d i s t a n c e over a l l  BELOW D I A G O N A L :  EDWARDS  POPULATION  loci.  (1971,1974) 1  1  AB  2  WB  0.0676  3  W  0.0940  "E"  DISTANCE 2  3  ****** ****** 0.1125  ******  242  Table 7 1 . IDENTITY).  SINGLE-LOCUS  GENETIC  SIMILARITY  (NEI 1978  UNBIASED  GENET!  COMPARISON LOCUS  TISSUE  AB-WB  WB-W  AB-W  IDH12  Muscle  0.9983  0.9998  0.9960  ME  Muscle  1.0000  1.0000  1.0000  IDH12  Heart  1.0000  1.0000  1.0000  AAT12  Heart  0.9983  1.0000  0.9983  MDH34  Heart  1.0000  1.0000  1.0000  PMI  Heart  1.0000  0.9957  1.0000  AGP12  Heart  1.0000  0.9920  0.9879  LDH-3  Heart  1.0000  1.0000  .1.0000  GL-1  Heart  0.9999  0.9999  1.0000  LGG-1  Heart  1.0000  1.0000  1.0000  IDH34  Liver  0.9800  0.8506  0.8495  F i g u r e 28. WAGNER TREE PRODUCED BY ROOTING AT MIDPOINT OF LONGEST PATH (Base measure used P r e v o s t i D i s t a n c e (Wright 1978)) ****************************************** DISTANCE FROM ROOT 0.00  0.00  0.01  0.01  0.01  0.02  0.02  0.02  0.02  0.03  0.03  *************************************** ****************** *  ************************************************************************************  \tfQ  * ***************************************************************************************************** ^  0.00  0.00  0.01  TOTAL LENGTH OF TREE =  0.01  0.074  0.01  0.02  0.02  0.02  0.02  0.03  0.03  244  Assortative situations  with  mating  and  non-random  there w i l l be an excess  generation.  with  respect  time  an  to  for  be  positive  in  others has  not  ability  by  other  occurs  to  identify  (Hartl  as  similar  examples genotypes  1976).  an  late  i n the  a s s o r t a t i v e mating  occurs  although  l e n g t h o f the  spp.  by  ( H a s l e r 1954).  I.Q.  Ehrman  proclivaty  breeding In  score.  as p r i m r o s e s ,  phenomenon (1970),  overall  season humans, Negative  where  there  a single  locus  of  "rare  Parsons  male  (1977)  and  Mate c h o i c e based on enzyme d i f f e r e n c e s fishes  great  P a c i f i c salmon have f r e q u e n t l y been  noted  between  might  be  their  et a l . 1986,  d i f f e r e n c e s i n metabolic  a s t r a y from another  a similar  i n the  of  the e a r l y p a r t  coded f o r by  the  length  individuals.  and  Rarely are t r a i t s  example.  to d i s t i n g u i s h  late  i n p l a n t s , such  mating  I f the  flower d u r i n g  height  mate  I f negative  might  1980).  blooming  of  occur  t o the  flower  for  waters by d i f f e r e n c e s i n odor (Groot Slight  positive  relative  been demonstrated i n f i s h e s but  their  1986).  of  plants that  in Drosophila  prowess i n o l f a c t i o n for  those  assortative  might q u a l i f y  are  of h e t e r o z y g o t e s  in plants  i s demonstrated  advantage" observed  with  be p o l l e n a t e d by p l a n t s with  mainly  i s h e t e r o s t y l y (Stebbins involved  example  i s limited  a s s o r t a t i v e mating  a s s o r t a t i v e mating  I f parents  excess  season  season w i l l  pollenated  relatives  p l a n t s which p r e f e r e n t i a l l y  e a r l y f l o w e r i n g and  will  an  classical  flowers  season then  the b r e e d i n g  mating.  then  flowering  individual  breeding of  A  between  o f homozygous i n d i v i d u a l s i n the progeny.  a s s o r t a t i v e mating o c c u r s next  mating  p o s s i b l e given  natal tributary Quinn and  enzymes might  population.  and  Tolson  allow  confleunt  1986,  a returning  Olsen fish  245  I f males and opposing  alleles  i n the next more than  females have d i f f e r e n t then  an excess  generation.  one  generation  unless  accompanied by  1974).  The  coding  normal  type  homozygote r e s u l t s  in s i c k l e - c e l l  and  malaria.  resistant  to  may  of  for  result for  different  be r e s p o n s i b l e f o r the  Overdominance has  is sensitive  anemia.  The  Heterozygote  to  inferiority  for  (Cavalli-Sforza  malaria  heterozygote  excess  been noted  c h a i n o f human hemoglobin  homozygote  fixed  l i k e l y to l a s t  unequal v i a b i l i t y  o f genotypes may  f o r the Beta  are  individual.  d e f i c i e n c y o f heterozygous i n d i v i d u a l s . alleles  or  from the expected  T h i s s i t u a t i o n does not seem to be  F i n a l l y , unequal v i a b i l i t y  the two  frequencies  of h e t e r o z y g o t e s  genotypes dependent on the sex o f the  or  allele  while  the  other  i s m i l d l y anemic  occurs  primarily  in  c o n j u n c t i o n with chromosomal a b n o r m a l i t i e s such as t r a n s l o c a t i o n s .  Ideally, following  conditions  population of  the  there  sizes  sex  ratio  : 1)  1:1.  of  overlap  different  violated  in  my  usually  between  size  should  non-overlapping  from  Typically,  several  population  from g e n e r a t i o n  i s a degree  maturity. in  effective  to  i n the  chum  Thus,  calculations. three  and  The four  to  every  fourth  year  as  a  salmon  average years  discrete  will  some  so  p o p u l a t i o n s i z e s from a p r o g r e s s i o n o f years size  3)  generations  a spawning p o p u l a t i o n years.  calculated  generations;  generation;  Although  be  2)  accounting are  due  extent  interval  to  a series  of  for  variation fish  the  one  birth  cannot  organisms i n age  condition to  death  reliably  cannot use However,  divergence  at  that were born  first  from  ( i . e . one  estimate).  the  semelparous  contain  that  using  under  is is use  population  interbreeding  246  between pool  fish  from  year  calculated ratio.  during to  different  year.  from data  years  should  Therefore,  tend  average  from s u c c e s s i v e y e a r s .  to homogenize the  population  size  gene  could  be  As w e l l , I have assumed equal  sex  G e n e r a l l y , d u r i n g the e a r l y p a r t of the spawning p e r i o d t h e r e are more  males than sex  born  ratio  females while  later  i s u s u a l l y 1:1  on  during  females predominate  the peak of the  run  i n numbers.  when the  However,  majority  of  the  f i s h are spawning.  The (1978)  Distance as  not  Wagner procedure  minimizing  acknowledged t h a t but  concluded  that  the  superior  minimizing  alternative  the  methods see  been  well  as  in this  procedure  Swofford  Wagner method was as  as  improvements  geaneologies.  well  SD  has  (1978)  Prager  and  other  aspect  was  still  finding  the  the  deviation. Wilson  by  Prager  procedures.  o f the  independently  i n both  standard  criticized  and  Wilson  Farris  (1978)  procedure c o u l d  best  method  concluded  be made  for a r r i v i n g  that  the  at  distance  most parsimonious s o l u t i o n as For  a  detailed  (1978), F a r r i s  discussion  (1978) and  of  Swofford  (1978).  The procedure timing  pattern  of  suggest  that  of  spawning.  the This  result  for  differences  among s e a s o n a l l y  may  lack  of  isozyme v a r i a t i o n  reflect  quantitative  an  historical  genetic  distance  populations  explanation  Given t h a t  the  genetic  is  success spawning  measures are  many  stocks  is relatively  separation  variation  has  d i v i d e d by  interesting of  and  the  distance  geography  because  i t may  i n v e s t i g a t o r s to using  rather  find  an  genetic  electrophoretic analysis.  populations.  been s u b j e c t e d  than  suggest  n e u t r a l to s e l e c t i o n these  among the  Wagner  results  In recent  times  to s e l e c t i o n caused by  the  247  separation undergone a genetic  i n spawning t i m i n g . form o f convergent  responses.  In e f f e c t , evolution  the  late populations  towards having  have p o s s i b l y  similar quantitative  248  Summary and S y n t h e s i s o f e m p i r i c a l r e s u l t s .  "...the  same o l d arguments  speciation,  no  matter  previously...Sympatric  are c i t e d how  again  decisively  speciation i s like  and again they  i n favor have  of  sympatric  been  t h e Lernaean Hydra which  disposed grew  new heads whenever one o f i t s o l d head was c u t o f f . " E r n s t Mayr  (1963)  two  249  Chum salmonid  salmon, species  Oncorhynchus with  keta,  considerable  Phenotypic  variation  among  differences  i n location  salmon  basis  f o r phenotypic  anadromous, variation  While  spawning l o c a l e s  variation  among  north  among  populations  o f spawning.  d i f f e r e n c e s a s s o c i a t e d with d i f f e r e n t genetic  an  phenotypic  chum  and season  is  is  temperate  populations.  associated  the g e n e t i c  with  basis of  i s w e l l e s t a b l i s h e d the  seasonally  separated  spawning  p o p u l a t i o n s has r e c e i v e d l i t t l e a t t e n t i o n .  Chum salmon l i f e  h i s t o r y can be d i v i d e d i n t o s i x phases:  coastal adult,  spawning a d u l t , egg t o f r y , downstream migrant, c o a s t a l j u v e n i l e and p e l a g i c juvenile. the  M o r t a l i t y and s e l e c t i o n  mortality  occurs  during  are s i g n i f i c a n t  the e a r l y  life  at each phase but most o f  history  i n t h e egg  to f r y ,  downstream migrant and c o a s t a l j u v e n i l e phases.  Phenotypic there  diversity  are s e v e r a l  levels  l e v e l o f the s p e c i e s . spawning,  time  among sexes, of genetic  o f spawning  and a b s o l u t e  organization  and " r a c e s " suggests i n chum  salmon  In p a r t i c u l a r , s e a s o n a l r a c e s may d i f f e r  morphology, d i s t a n c e migrated maturity,  populations  migration,  time  o f spawning,  size  that  below the  in location of at m a t u r i t y ,  from the sea, average weight o f spawners, age at  fecundity.  Cold  season  upstream, be l o n g e r , h e a v i e r , more fecund,  spawners can migrate  further  mature at o l d e r ages, have slimmer  b o d i e s , slimmer heads and longer p e c t o r a l f i n s than warm season spawners.  250  Several  hypotheses  seasonally separated its  flaws  and  only  have  been  proposed  to  account  spawning p o p u l a t i o n s i n f i s h e s . Frost  (1966) has  approached  for  the  evolution  However, each theory  the  problem with  of has  a genetical  perspective.  The  analyses  separated  chum  of  phenotypic  salmon  and  populations  has  seasonally  confounded  with  geographic  apart.  The  l i n k between season o f r e p r o d u c t i o n and temperature of development  raises  the  environmental  that  a l l phenotypic  r a t h e r than g e n e t i c  results  o f my  stocks  among  since  possibility  separated  been  diversity  separation  The  seasonally  genetic  may  also  diversity  spawn  observed  100's  of  i s caused  different  i n v e s t i g a t i o n s at Bush and  stocks  i n these  spawned mainly WB,  i n phenotype. rivers:  an  from l a t e  Walker c r e e k s  I e s t a b l i s h e d that autumn  spawning  there  suggest  stock,  AB,  were t h r e e i n Bush  September t o mid-November; a winter  a l s o i n Bush Creek t h a t spawned from the end  December i n Bush Creek; and  by  factors.  s e a s o n a l l y s e p a r a t e d p o p u l a t i o n s o f chum salmon i n the same l o c a l e may very  km  a winter  that  not  spawning  Creek  spawning  that  stock,  of November to the middle  spawning s t o c k , W,  be  of  i n Walker Creek t h a t  spawned from the end o f November to the end o f December.  WB  spawners had  fewer v e r t e b r a e than s p a t i a l l y s e p a r a t e d W and  separated  AB.  Age  that  late  stocks  the  Length at age  was  of  spawners was combined  had  similar younger  i n 1981  and  spawners  a l s o s i m i l a r among the p o p u l a t i o n s  1982  than  i n 1981  temporally  with AB and  exception  during 1982  1982. except  251  that  in  1982  separated  the  late  s t o c k AB.  stock,  the w i n t e r in  much c o o l e r  regime  in  early  the  stocks, W pattern  and  was and  emergence  winter s t o c k s . TU's  WB  than  between  the  autumn  stock  and  stock while  must the  experience  winter  stocks  relatively would  warm  experience  WB,  was  consistent c o u l d not  be  much s h o r t e r than even  progeny  though  accounted  the  f o r due  t h a t o f the autumn s t o c k , years  were  that  winter  AB  had  required  s t o c k s had  more  similar  TU  TU's  to  i n 1982  and  emerge  between the two  others.  great among the s t o c k s .  fewer  The WB  AB.  different  differences  than The  the  two  number  of  year.  than the s p a t i a l l y s e p a r a t e d W and t e m p o r a l l y s e p a r a t e d AB e x t e r n a l morphology was  two  u n i t s (TU's) used t o  requirements.  c o n s i s t e n t from year to  more v e r t e b r a e  quite  to environmental  C a l c u l a t i o n s o f the number o f thermal  showed The  a synchronous emergence  Thus, the i n c u b a t i o n p e r i o d to emergence o f the  r e q u i r e d f o r each s t o c k was  The  temporally  s m a l l e r eggs at. l e n g t h  p a t t e r n of f r y run t i m i n g suggested  among the streams. reach  the  S i n c e the streams d i d not d i f f e r g r e a t l y  autumn  development  p a t t e r n among the s t o c k s .  climatically  stock had  than  temperatures.  the temporal  This  spawners  i n c u b a t i o n environment  s t o c k s were s u b s t a n t i a l .  temperatures  larger  stocks.  i n the  temperature  winter  had  Females of the WB  e i t h e r o f the other two  Differences  WB,  vertebrae stocks.  s t o c k was  in  Overlap  1983 in  intermediate  252  Returns was  of  marked f i s h  substantial.  However,  more  showed  Straying  than  into  of  70?o  that  the  the  straying  among t h e  W and AB s t o c k s  spawners  in  three  populations  was  less  than  be  from  the  WB c o u l d  1 2 - 1 3 %. other  two  populations.  To s u m m a r i z e t h e r e s u l t s the  stocks  winter be t o  in  the  spawning  wild:  stocks  compensate f o r  1) are  divergent  temporally general timing  and  all of  other  the  strays  probability  different.  W and  were  into mate  a resident  greater  for  WB f i s h  adapted  to  season  of  had  The  as  morphology  of  progeny,  W or  reproduction  AB; to  and  area  is  is  populations morphology of  the  showed of  three  fry  using that all  laboratory for  compensate  three  categories  of  stocks traits  are is  rate,  affected  progeny  Whether  matter  but  the  substantially appear  to  differences  by  of  number  different.  also  from  be in  development.  vertebral  genetically  In  spawners,  great.  rates the  both  straying  must be  for  of  of  3)  another  incubation  rearings  incubation  ;  the  traits.  length  very  an o u t s i d e r 4)  separated  phenotypic  t e m p e r a t u r e e x p e r i e n c e d by t h e s t o c k s d u r i n g e m b r y o n i c  Investigation  WB a p p e a r e d t o be  age  f i s h mates w i t h  and  incubation environments  populations  residents  autumn  to  in  the  the  appear  similar  with  of  t i m e does not  convergent  t h e WB s p a w n i n g  compared t o of  AB,  quite  and e x t e r n a l  populations  that  Spawning  (1984) f o r s o c k e y e s a l m o n ; 2 )  spatially,  successfully  environments  i n temperature  phenotypically.  populations  two  very  and e n v i r o n m e n t a l - v a r i a t i o n among  incubation  population  emergence  the  the  differences  h a s b e e n n o t e d by B r a n n o n most  for phenotypic  the  the and  three external  However, temperature  each of  253  incubation. stock  S u r v i v a l d u r i n g embryonic development appeared to be u n r e l a t e d to  or temperature  experiment.  of incubation.  S u r v i v a l was much  1982-83  rearings. days  experiment  In both  t o reach  matings  when  t o be  trials  50% hatch reared  under a s i m u l a t e d required  i n the 1982-83  T h i s appears t o be due t o t e c h n i c a l problems i n r e a r i n g and not  n e c e s s a r i l y r e l a t e d t o the treatments. the  lower  fewer  days  significance,  under  those  from  o f the 1983-84 l a b  o f autumn stock matings r e q u i r e d more  a simulated  spawned" regime. than  I consider the r e s u l t s  than  and 50% emergence than  t o hatch  populations  reliable  the o f f s p r i n g  a t 6 C,  "winter  less  Therefore,  "autumn  o f winter  spawned"  stock  regime  and  At 10 C the autumn spawning s t o c k  the winter  t h a t were both  the progeny  stocks.  spatially  In o v e r a l l  and t e m p o r a l l y  tests  of  i s o l a t e d or  spawned d u r i n g d i f f e r e n t seasons were the most d i v e r g e n t .  AB  and WB  counts w h i l e WB of  were the l e a s t  treatment  revealed  progeny  and  greater  than  Eye  over  and  analysis  and  o f each  observed  of W  WB  was  separated  and WB.  among the w i l d  snout  standard  to v e r t e b r a l  There was no d i s t i n c t t h e most  The  progeny.  ordering  responsive  to  responsive.  samples  a marked s e p a r a t i o n by e x t e r n a l morphology  t h e progeny those  o f pooled  respect  by  temperature  between the AB  d i f f e r e n c e s were  much  When the samples  were  a l l temperatures the d i s c r i m i n a t o r s i n order  diameter,  depth  i n mean v e r t e b r a l count.  with  i n c u b a t i o n temperature w h i l e W was the l e a s t  Discriminant  pooled  populations  and W were the most s i m i l a r .  the p o p u l a t i o n s  different  similar  o f importance were:  l e n g t h , p a r r marks, p e c t o r a l f i n l e n g t h , head l e n g t h , head length.  At a l l temperatures  the AB  progeny  had l a r g e r  254  eyes.  The  AB  progeny  From the r e s u l t s differs  generally  among a l l t h r e e s t o c k s .  t r a i t s time t o hatch  all  stocks.  and  0.47  time  Sire  f o r AB,  to  The and  p l u s dam WB,  and  than  the  winter  stocks.  f o r e x t e r n a l morphology  d i f f e r e n c e appears to be g r e a t e s t between each o f  the  two  winter  spawning  stocks,  W  effects  were not  Electrophoretic populations  that  only  a  could  not  0.40  In  a l l cases  of  39  than  that  and WB  WB,  amount  loci  of  genetic  the  revealed  W,  for  respectively.  heritabilities  that  differentiation  The  possibilities  they  0.35  heritabilities  and  t h a t h e t e r o z y g o s i t y was  among the p o p u l a t i o n s .  other  dam  were 0.27,  were  zero.  analysis  e l i m i n a t e the  constructed the AB  f o r AB,  were  that  occurs  to  the  there  split  up.  was  from the WB  W  and  higher  loci  in  than  WB  expected suggest  i n biochemical  traits fixation  i n t e r b r e e d i n g among  stock  i n t o the AB  were more c l o s e l y  had  the  F ( s t ) values  no  population.  i n d i c a t e d t h a t the W p o p u l a t i o n  p o p u l a t i o n s had  many  p a t t e r n s of polymorphism and  d i s t a n c e measures i n d i c a t e d t h a t AB  each  plus  0.54  important.  the p o p u l a t i o n s or t h a t m i g r a t i o n Genetic  and  Sire  were i n Hardy-Wienberg e q u i l i b r i u m .  limited  has o c c u r r e d  f o r time to hatch  respectively.  were polymorphic and  populations  time to emergence proved to be h e r i t a b l e i n  heritabilities  W,  s i g n i f i c a n t l y g r e a t e r than  the  and  emergence were 0.50,  Maternal  to  snouts  WB.  The  if  longer  i t i s c l e a r t h a t the g e n e t i c program  the autumn spawning s t o c k , AB, and  had  A  Wagner  diverged  first  stock. related  Tree  was  and  then  255  The  r e s u l t s suggest  phenotypes operating  of so  a s i t u a t i o n as f o l l o w s :  conspecific  that  there  populations  that  i s convergence  S t a b i l i z i n g s e l e c t i o n on inhabit  in t r a i t s  the  same  required  the  locale  to s u r v i v e  is  i n the  common environment.  Certainly after  they  these  emerge  environments  of  populations  and  the  migrate  do  inhabit  downstream.  s e a s o n a l l y separated  basically However,  genetics  of  different  development directions  differences  uniform  environment.  can  one  to  experienced  relatively  relatively  the  An  s e a s o n a l l y separated compensate  during  phenotypes  explanation  needed  such  as  so  to  this  the  results  amount o f s t r a y i n g among the i n d i c a t e t h a t the p o p u l a t i o n s  of  the  or  for  that  survive  of  may  to  attain  the  account  that  for  the  However,  how  show  a  large  electrophoretic results and  WB,  in  post-emergent  i n the w i l d .  i n the same stream, AB  the  environmental  the  experiments the  level  there  have evolved  they in  incubation  different  the  is sufficient  tagging  populations  so  populations  s i m i l a r phenotypes among the p o p u l a t i o n s  resolve  are  environment  the  Thus at the  genetically  development  same  because  populations  e x i s t s a k i n d o f d i s r u p t i v e s e l e c t i o n between them.  the  that  are more c l o s e l y  r e l a t e d than those o f the same season?  The and  late  h i g h r a t e o f s t r a y i n g seems c o n t r a d i c t o r y to the populations  demonstrated  that,  are  i n the  i n d i v i d u a l per g e n e r a t i o n populations.  sufficiently absence was  of  isolated selection,  sufficient  to  diverge.  migration  t o homogenize the  In the past many s t u d i e s s u g g e s t i n g  i d e a t h a t the e a r l y  of  Spieth less  than  gene p o o l s  that phenotypic  (1974)  of  one two  differences  256  among  populations  populations  were  were  a  reflection  discredited  using  r e c e n t l y i t has been suggested generation than  were not s u f f i c i e n t  1000 i n d i v i d u a l s  i s important  involving one  involving may  populations  the  logic  transfer into  differences  Spieth  resident  1987).  Endler  of  can be both  from one area  genetic  the  breeding  population.  material  between  time  place  and  ecological  migration  i n a simple  influences 1987).  population  favored  structure  C e r t a i n l y there  (Bull and  i s no doubt  populations. of  does  et  a l . 1987).  the three p o p u l a t i o n s but i t i s not c e r t a i n  the highest,  Genetic  migration  that there  other  t h e r e f o r e a c t s on  i s complex  ecological  the  not i n f l u e n c e  the movement y i e l d i n g  i t s evolution that  and a g e n e t i c  successfully find a  (by d e f i n i t i o n ) and n a t u r a l s e l e c t i o n  is  differentiation.  t o another  structure  success  migration  (Bull  et a l .  occurs  between  i s much gene exchange.  The a n a l y s i s o f polymorphic enzyme p a t t e r n s i n s e c t i o n 6 i n d i c a t e s t h a t is l i t t l e from WB system. rate  genetic migration  to AB.  T h i s may  between the p o p u l a t i o n s .  represent  Of the p o p u l a t i o n s , WB,  o f s t r a y i n g from o t h e r  i t s small population  populations  shows the most  fluctuation  from the norm  size  i s the most l i k e l y  m i g r a n t s t o d i s r u p t i t s response t o the s u r r o u n d i n g  selective  i n phenotype.  there  The only p o s s i b i l i t y i s  the t r u e l e v e l o f g e n e t i c i s o l a t i o n  with  that  an e c o l o g i c a l phenomenon  E c o l o g i c a l migration  manner:  of greater  (1986) suggests  population  reproductive  the  However,  i n populations  but i t does n e c e s s a r i l y f o l l o w t h a t they w i l l  i n the  among  (1974).  t o s e t the l e v e l o f g e n e t i c  that migration  stray  of  t o impede s e l e c t i o n  interact  recognize  genetic  that r a t e s o f m i g r a t i o n as h i g h as 6 a d u l t s per  the movement o f i n d i v i d u a l s  Individuals  mate  the  (Wehrhahn and Powell  s e l e c t i o n and gene flow It  of  i n the  and the h i g h  t o r e c i e v e enough forces.  It a l s o  From t h i s I p o s t u l a t e  257  that  genetic  migration  r'rom responding also  note t h a t  fertility  there with  are  I was  probably  reduction  may  a  not  series  variation  in  morphological, study.  of  of b a r r i e r s  being  just of  to  one  ecological,  and  gene  at  the  and  electrophoretic morphological,  meristic  i n I r e l a n d was  protein  morphs  data  to  Similarly,  of and  not  traits  r a t e s o f organismal  of  structural  proposes  that  the  In  by  the  1980).  detectable  dilemma  t h a t the r a t e s o f m o l e c u l a r  the  i s the  W  populations  product  barrier  that  that and  this  from  of  the  gives  the  analyses  of  characteristics i s v a r i a b l e from  subspecies  (1980) was of  results  According  in  able  as  study  to  to s e p a r a t e  great  among  charr  populations  Clayton  of  can  be  in  Artie  structural  (1981)  many  between  evolution (evolution  electrophoresis).  creates  organismal  molecular  the by  divergence  from a n a l y s i s o f to  prawn,  i s o n l y a tenuous correspondence  by  the  such  the  Windermere  contrast,  features  ( p o l y g e n i c t r a i t s ) and  proteins  and  a b l e t o use the agreement between  races  ecological  i n v e s t i g a t i o n s have shown t h a t t h e r e the  It  results  Child  isozymes.  matched  (Ferguson  must  t o remember that  among  each  define  seasonal  analysis  One  it  at a l l i f there i s  flow  taxonomic  behavioural  allozymic  distinct  f o r phenotype.  i s important  aspect.  between  enzymes  morphologically  prevent  ( F i g u r e 29).  congruence  Macrobrachium r o s e n b e r g i i .  charr  It  crossmating  polymorphic  and  might  i n r e a r i n g c r o s s mated progeny o f WB  For example, L i n d e n f e l s e r (1984) was  morphometric  populations  selection  populations.  probability  degree  other  r e c i e v e many v i a b l e migrants  true l e v e l of genetic i s o l a t i o n  The  the  to s t a b i l i z i n g  among the  isolation  i n the  from  unsuccessful  WB  barrier  temporal  WB  effectively  i n the l a b o r a t o r y . a  into  Clayton  resolved  evolution d i f f e r  by  (1981)  postulating  in nature.  258  Pj= percent isolation SEASONAL OR HABITAT ISOLATION n  ETHOLOGICAL ISOLATION  MECHANICAL ISOLATION  GAMETIC MORTALITY  p  ZYGOTIC MORTALITY  p 5  HYBRID INVIABILITY  p  P  p  2  3  4  c  0  6  HYBRID STERILITY  p  ?  Probability of a successful migrant equals P, • P P 3 - P - P ^ 2  F i g u r e 29.  4  5  B a r r i e r s to c r o s s m a t i n g showing the cumulative e f f e c t on g e n e t i c m i g r a t i o n ( A f t e r Mayr 1970).  259  Clayton  (1981)  invokes  the  "molecular  e v o l u t i o n proceeds  at a steady  the  have  fossil  (Gould  and  record  may  emphasized  E l d r i d g e 1977,  disparities  between  rate.  divergences  hypothesis  In c o n t r a s t , modern  the  Stanley  clock"  erratic  1979).  pace  Clayton  estimated  from  of  that  molecular  interpretations  organismal  evolution  (1981) proposes  molecular  and  of  that  the  organismal  data  be i n t e r p r e t e d as r e f l e c t i o n s o f the e r r a t i c pace o f organismal e v o l u t i o n .  If  one  between  the  those  from  accepts  this  as  a  incubation rate, electrophoretic  interesting  conclusions.  reasonable  meristic  analysis First  and  explanation  the  differences  morphological, r e s u l t s  f o r these  one  for  must  populations  conclude  that  compared  one  may  the  divergence  to  make some in  q u a n t i t a t i v e t r a i t s among the s e a s o n a l l y separated p o p u l a t i o n s must have taken p l a c e a f t e r the s e p a r a t i o n o f the Walker Creek p o p u l a t i o n from  the Bush Creek  populations.  I conclude we  would expect  AB.  Given  this  t h a t WB  that there  p o p u l a t i o n s by  hypothesis  for  population,  probably  that  population.  separated  first  isozyme f r e q u e n c i e s would be more s i m i l a r t o W than t o is relatively  system. spawning system.  somewhat  These f i s h may  genetic d i f f e r e n t i a t i o n  must conclude  recent.  Thus, one  Originally only At  later  little  data one  is relatively  this  more s t a b l e  returned  i f the s e a s o n a l p o p u l a t i o n s had  electrophoretic  quantitative t r a i t s  larger,  because  in  Bush  there Creek  the  have found  year  than  divergence  must modify may  have  as  some p o i n t t h e r e may in  t h a t the  among the  the  been  i t appears  the  main  original only  to  have developed group  in  be  one the  a group in  the  most of the spawning s i t e s occupied or  260  conditions to nearby allowed allow  i n Bush Creek l e s s than Walker  Creek.  the  late the  fish  winter  adapted to t h e i r  e x p l a i n the  colonize  separation  stock  the  rapid  the  Wisconsin  incubation  to  10,000 years  it  i s now  late  and  problem  and  later  the  stocks.  winter  Creek may  W stock  the  Bush stock  itself. but  The  two  in different  ways.  b a r r i e r among the  could  and  thus  continued  winter  s i n c e they had  different  stocks  as  to  spawned a  stocks  T h i s would  two  have  This  months  The  Some time l a t e r  have  starting elegantly as  the  i s p o s s i b l e t a k i n g i n t o account c o n d i t i o n s at  the  One  might  ago.  suppose  A l s o , Ladysmith Harbor may  the  Walker c r e e k s  could  have  may  evolved  same r i v e r .  As  the  lengthened these s t o c k s became s e p a r a t e d later  into  among the  Glaciation.  Bush and  of  i n Walker  well  that  populations  with  r a t e s would be s e l e c t e d f o r i n the c o l d c l i m a t i c p e r i o d 8,000  populations  tributaries  thus been a t t r a c t e d  s i z e among them.  An a l t e r n a t i v e s c e n a r i o of  further  i n Bush Creek  apparent i n f e r t i l i t y  d i f f e r e n c e i n egg  end  warmer water  season o f r e p r o d u c t i o n  have s o l v e d  f o r spawning and  j u s t enough to make them v i a b l e .  l a t e season n i c h e .  spawning  they  to  temporal  adapt to the new  points  slightly  t h e i r progeny to c a t c h up  increase  new  The  ideal  i n the  year.  Finally  have been much s h o r t e r  have been one as  stocks  climate  system. spawning  warmed  by geography and an  earlier  and  Thus, the in  than two  different  Ladysmith  Harbor  were f o r c e d to spawn  spawning p o p u l a t i o n  evolved  in Bush Creek.  One traits  other  thought  interesting result to be  r e l a t e d to  that  fitness,  seems  difficult  to  time to hatch and  resolve  is  that  time to emergence  261  have  relatively  high,  non-zero  heritabilities.  of natural s e l e c t i o n postulates mean  f i t n e s s equals  1930).  Natural  fitness  the  variance  in  Falconer  additive  selection  differences  be  heritabilities.  Further,  drive  equal  be  fitness  the  soon  the  depleted  related  when t r a i t s  affected  the  switching might  that  norm  the  of  animals  does not  come to  does  not  natural  cannot  be  effectively  Many deaths by  f i t n e s s o f the  the  to  are  work  due  selection  organism.  A  to ever  third  equilibrium  cannot  be  are  achieved.  negatively  genes d i e because these genes produce l e t h a l  with  I  simply  the  as  I  words  my  system  environment  effeciently  s t o c h a s t i c processes though  the  possibility  as that  traits  i s that  genes f o r  optimal  by  one  i s t h a t the in  may  Thus  other  I  1981).  artificial  c o r r e l a t e d with  Individuals  zero  explanation  In  nearly  e x i s t s a n t a g o n i s t i c p l i e o t r o p y such t h a t the more o p t i m a l r a t e a l s o code f o r e f f e c t s t h a t  (Falconer  an  noise  to  or  1981).  trait.  i s continual  processes  tracked  of  to  low  laboratory  (Hartl  genetic  According  The  Another p o s s i b i l i t y  There  selective  (1930) e n v i s i o n e d .  t o the  field.  traits  where  s e l e c t i o n , as  diminish  i n the  (Fisher  the  very  stabilizing  environment  heritability  to the  Fisher  important  the  these  change i n  equilibrium  1955).  o f t h i s quandry.  from  the  to  have  should  theorem  fitness i t s e l f  consequently  I measured h e r i t a b i l i t y  equilibrium.  allow  under  variance  for  apply  and  should  are  reaction  substantially alter  lab r e s u l t s do not  that  since  in  (Robertson  traits  fundamental  of evolutionary  population  zero  There are s e v e r a l p o s s i b l e ways out q u i t e simply  variance  to  have proposed here, a d d i t i v e g e n e t i c  be  mean r a t e  genetic  will  will  fitness will  (1981)  that  Fisher's  are there  incubation  fitness.  Thus  incubation  rate  phenotypes f o r other  traits.  A  262  fourth  possibility  is  i f the  seasonal breeding n i c h e s then gene  pools  argued  to  on  in  occurring.  Lande  thousands o f variance  grounds  replaced  found  that  in  r e c e n t l y occupied  that  and  at  given in  that  the  not had  (1975) and  additive  even  (1975) argued  be  Lande  that  populations  mathematically  he  Finally,  genes s e g r e g a t i n g  would  determined example  wild  have  n a t u r a l s e l e c t i o n has  equilibrium.  theoretical  maintained  populations  genetic  that  there  time  same  virtue  rate  is  selection  i n male  salmonids  by  virtue  of  their  traits  a l . (1988) have  i n salmonid  The  two  seasonal  and  1988)  landscape.  noted  high  traits of  fry  of  heritability  interest,  migration  alone Arnold  be  genetic (1986) For  stabilizing  trait  ancestry  by no more  can  Both Gjedrem  levels  seasonal  may  be  timing  considered  the q u a n t i t a t i v e g e n e t i c s o f development. evolution  Within  consists  Wright's  s t o c k s occupy d i f f e r e n t  (parts  the  adaptive  of  movements  (1931) h y p o t h e s i s  separated of  must  in  maintain (1983) and  fitness  related  populations.  main  timing  heterchrony (1969,  there  salamanders  tetraploid  higher l e v e l s of v a r i a t i o n i n f i t n e s s r e l a t e d t r a i t s . et  selection  t h a t t h e r e are l i m i t s to s t a b i l i z i n g s e l e c t i o n . sexual  be  35%.  Perhaps  Gall  have  could  strong  lost.  s e l e c t i o n c o u l d reduce the v a r i a n c e o f a normally d i s t r i b u t e d than about  (1986)  variance  o f mutation  i t was  to b r i n g the  Arnold  quantitative t r a i t s by  different  adaptive  complex are  the  the  on  a  of  spawning  as  a  and  function  the of  A c c o r d i n g to Wright genotypic  genomes of  peaks o f coadapted  the gene  adaptive seasonally complexes  genes f o r season of spawning and  the  263  genes f o r the speed o f embryonic development). the  Wright  s e l e c t i v e peaks do not depend on the s t r i c t  component  genes.  There  may  be  gene  (1988) p o i n t s out that  a d d i t i v i t y o f the e f f e c t s o f  interactions  (epistasis)  such  as  heterochrony.  Heterochronic change  e f f e c t s can p r o f o u n d l y a l t e r the phenotype without  i n the genome.  ontogenetic  Atchley  trajectory  of  a  phenotype.  Slatkin  heterchrony  t o show how g e n e t i c  variation  and  (1987)  trait  can  has examined result  covariation  variation  i n phenotypic  f r y ) during  i n d i v i d u a l d u r i n g the e n t i r e  It or  is difficult  different  impinge  forms  life  of a species  traits  "host the on and  races",  "ecological  same t e r r i t o r y (White disruptive Boam  history  genetic  without  of speciation.  However,  and  how  divergence  in  genetics of  selection  on the  According to  ( i . e . to reproductive  can a f f e c t  divergence  considering As s t a t e d  the f i t n e s s  adult o f the  among e c o t y p e s , how  races  the r e s u l t s  might  i n the i n t r o d u c t i o n ,  the  i s the most widely accepted mode o f s p e c i a t i o n  given: races"  1) t h e e x i s t e n c e or " a l l o c h r o n i c  of "biological  races"  1978) and 2) t h e r e s u l t s  s e l e c t i o n by v a r i o u s r e s e a r c h e r s  1959, Thoday  i n the  history.  to investigate  on the t h e o r i e s  1979).  in striking  o f developmental parameters.  the l i f e  a l l o p a t r i c model o f s p e c i a t i o n (Futuyma  change  i n developmental parameters governs  S e m l i t s c h et a l . (1988) t i m i n g o f t r a n s f o r m a t i o n s t o emergent  a  (1987) developed a model f o r the q u a n t i t a t i v e  phenotype a l t e r s the d i s t r i b u t i o n s  or  how  a large  of a species  of laboratory  races", within  experiments  (Thoday and Gibson 1962, Thoday  1972, P i m e n t e l e t a l . 1967) and evidence  for selection  264  against hybrids be  considered  i n t h e w i l d (Dowling as a d e f i n i t e  and Moore 1985) sympatric  possibility  (Dickson  s p e c i a t i o n must  and Antonovics  1973, Bush  1974).  Races or ecotypes 1983).  Some  examples  Oncorhychus nerka, Artie  charr,  seasonal  a r e a common  feature  a r e kokanee  (Foote  and  o f salmonid  sockeye  salmon  (Saviattova  i n the s p e c i e s ,  1987, F o e r s t e r 1968), F - c h a r r , normal and S-charr i n  Salvelinus alpinus  (Nyman  1980),  and t h e numerous  examples o f  races ( F r o s t 1966, Berg 1934, 1959, R i c k e r 1972).  According speciation  to  Maynard-Smith  i s the e s t a b l i s h m e n t  environment. Maynard-Smith  Given  (1966)  the  crucial  a polymorphism,  such  as observed  in  sympatric  i n a heterogenous  with  seasonal  races,  (1966) proposed that r e p r o d u c t i v e i s o l a t i o n need only e v o l v e f o r  s p e c i a t i o n t o be p o s s i b l e .  In s e a s o n a l l y  one  both  one.  physiological  step  o f a s t a b l e polymorphism  sympatric has  species  criteria readiness  rolled  into  t o spawn r e p r e s e n t s  The  a l l o c h r o n i c populations  seasonal  a striking  differences i n  polymorphism  and a l s o  s e r v e s t o i s o l a t e the p o p u l a t i o n s .  Although  the step  of establishing a stable  s e l e c t i o n seems f o r m i d a b l e , one can develop genetic  model.  specific  locus  Suppose T.  Also  that  selection  suppose  progeny) d u r i n g a p a r t i c u l a r  that  polymorphism  a mechanism f o r t h i s with a simple o f spawning  reproductive  season  success  i s due t o one  (the s u r v i v a l o f  season depends upon one l o c u s E.  example E c o u l d c o n t r o l time t o emergence.  by d i s r u p t i v e  In t h e present  I n d i v i d u a l s t h a t emerged t o o e a r l y  265  " T l — T 1 " i n d i v i d u a l s spawn i n  or l a t e i n the s p r i n g c o u l d be s e l e c t e d a g a i n s t . the  autumn.  "T1-T2"  winer.  "T2-T2"  develop  slowly  develop  slowly.  i n d i v i d u a l s spawn  i n d i v i d u a l s spawn -  time  to  either  during  emergence  the  is  This  arrangement  individuals  spawning  i n the  will  cause  autumn  and  autumn  winter.  longer.  "E2-E2" i n d i v i d u a l s develop  shorter.  during  or  during  the  "E1-E1" i n d i v i d u a l s  "E1-E2"  individuals also  r a p i d l y - time to emergence i s  a  steady  increase  in  T1T1E1E1  T2T2E2E2 i n d i v i d u a l s spawning  in  the  winter.  Is  this  believe  the  plausible system  in  must  terms  be  traits.  However, Tauber et  seasonal  isolation  found time  that to  some  needed  more  locus  in  complex  species  information?  than  of  above  Chrysopa.  c o n t r o l l e d the  rainbow  undisputed  empirical  and  Personally,  involve  a l . (1977) showed t h a t o n l y two  among two  PGM-1  hatching  contains traits  the  of  trout,  examples  Salmo of  rate  simple  o f embryonic  f o r a model o f s p e c i a t i o n by  control  allochrony.  As  al.  (1983)  development  Thus,  genetic  polygenic  genes c o n t r o l l e d  A l l e n d o r f et  gairdneri.  I  the  and  literature  over  w e l l , my  the  key  results  show t h a t among s e a s o n a l l y s e p a r a t e d  groups the r a t e of development i s adapted  to  i n the  the  season  downstream separated  of  spawning  migration populations.  is  and  that  synchronous That  wild  among  stabilizing  a narrow window o f time e x i s t s f o r the  been  demonstrated  Fresh  et  Walters et a l . (1978) and Brannon  al.  (1985),  (1984).  timing  progeny  s e l e c t i o n operates  that  by  the  the  of  of  emergence the  on  and  seasonally  fry timing  so  f r y to migrate s u c c e s s f u l l y has Taylor  (1980),  Bilton  (1980),  266  Aside on  from the i m p l i c a t i o n s f o r e v o l u t i o n a r y theory  the management o f a q u a c u l t u r e  (1988) concluded in  fishery  variance  t h a t two f i e l d s  biology:  in a fish  environmental  genetics species  change  and f i s h e r i e s . badly and  The  i n a serious  1986, 1987, Kapuscinski  annual m i g r a t i o n  t o the f i s h e r y .  of  extinguish  the year  may  review  Gerking  reduction  and Lannan  genetic  1986).  These  season o f spawning, and g e n e t i c s :  t i m i n g which  Spawning time i s  in turn  Heavy e x p l o i t a t i o n d u r i n g  a unique s t o c k  of  loss of adaptability to  the r a t e o f i n c u b a t i o n and r e s u l t i n g morphology o f t h e f r y .  the a v a i l a b i l i t y  impinge  In a recent  behaviour.  r e s u l t s suggest a l i n k between a b e h a v i o u r :  c l o s e l y c o r r e l a t e d with  results  need a t t e n t i o n i f we are t o move ahead  can r e s u l t  (Meffe  these  i s connected t o  a particular  time  even when the annual e x p l o i t a t i o n  r a t e on the s p e c i e s i s at low l e v e l s .  Another concern i s the i n t r o g r e s s i o n o f  hatchery  For example, L e i d e r e t a l . (1986) found  stock i n t o wild populations.  t h a t the success only  o f hatchery  28% o f t h a t  of wild  steelhead  fish.  t r o u t i n producing  Yet due t o the r e d u c t i o n  rearing  artifically  62% o f the n a t u r a l l y produced  hatchery  spawners.  C h i l c o t e e t a l . (1986) concluded  could  threaten  populations means  that  appropriate  the g e n e t i c  are adapted hatchery  integrity  of wild  by i n c u b a t i o n  operators  smolt o f f s p r i n g was  should  rate take  smolts  were  to t h e i r  o f the time t o hatch  be r e l e a s e d .  On the other  operations  The r e s u l t  season  of  hand  that  reproduction  t o use broodstock  g e n e t i c make-up t o both the season o f r e p r o d u c t i o n  where the progeny w i l l  offspring of  t h a t hatchery  populations.  care  i n m o r t a l i t y by  with  the  and the l o c a l e  the h i g h  heritability  and emergence suggests t h a t b r o o d s t o c k s c o u l d be s e l e c t e d  f o r emergence at a p a r t i c u l a r time as needed by the hatchery  operator.  267  Returning  to  t h e s i s . . . There  are  separated  would  that  differences achieved  not  questions great  populations.  environment suggests  the  lead  be  phenotypic  However, one  phenotypes  can  posed  to  are  considered  in  the  differences  since  expect  the  adaptive.  to The  among  the  an  in  incubation  The  of  optimum.  difference  Therefore i n phenotype  by d i f f e r e n c e s i n the genomes among the p o p u l a t i o n s .  are c l e a r l y g e n e t i c a l l y d i f f e r e n t .  the  seasonally  lack  similarities  of  these  difference  differences  constrained  introduction  The  the are  populations  c a s u a l f a c t o r s f o r t h i s d i f f e r e n c e are  not e n t i r e l y c l e a r although  I suggest t h a t s t a b i l i z i n g s e l e c t i o n f o r phenotype  of  the  the  emerging  fry  among  genotype f o r i n c u b a t i o n r a t e and  populations  and  d i s r u p t i v e s e l e c t i o n on  f r y morphology are  responsible.  The g e n e r a l wisdom among salmon b i o l o g i s t s i s that a d u l t migratory has  evolved  to  maximize  Roberson 1986).  successful  In p a r t i c u l a r , time o f m i g r a t i o n  ensure a time o f f r y m i g r a t i o n (Merritt  and  temperature isolation  Roberson  1986).  regime o f the of  reproduction  that w i l l  home stream  stocks.  Brannon  Fraser River  time has  evolved  (1962) found inland  in  to  that  streams  spawning  drainage.  the  of  offset  spawning  Miller  southeastern  warmer  coastal  pink  and  (1984)  and  temperature of  and  1982,  Brannon  (1982)  observed  later  Brannon  s e l e c t e d to  sockeye  Alaska streams.  occurred Sheridan  earlier  that  salmon  i n warmer streams o f  (1982) proposed  (Oncorhynchus  survival  suggested  that  d i f f e r e n c e s among streams.  salmon  and  f o r the e c o l o g i c a l  that  i n the year  timing  Merritt  spawning was  i s most r e s p o n s i b l e  (Oncorhynchus nerka) spawning o c c u r r e d the  (Mundy  maximize the p r o b a b i l i t y o f  Miller  the  Sheridan  gorbuscha) in  the  spawning  in cold,  year  (1962) demonstrated  than that  268  despite  a  46  day  difference  Kadashan Creek and those  i n spawning  times  between  pink  salmon  using  u s i n g Klawock Creek, the ova r e c e i v e d about the same  number o f temperature u n i t s by s p r i n g , so t h a t  f r y o f both streams emerged at  about the same time.  However,  spawning  time  i n chum  temperature o f the spawning stream.  salmon  has not e v o l v e d  to offset  E a r l y spawners l a y t h e i r  the  eggs at h i g h e r  temperatures than l a t e r spawners and must accumulate more temperature u n i t s t o complete  embryonic  absolute  i n c u b a t i o n r a t e s than the e a r l y spawners.  According  t o Lynch  promote u n i f o r m i t y may  be prevented  selection  (1986) t h e r e  among  isolates  with  a high  component  the same c o n c l u s i o n  pathways.  Favored  r e l a t i v e and  i n the f a c t o r s  Population  or by o p e r a t i o n  1986).  Ehrlich  of s i m i l a r  and Raven  i s the primary c o h e s i v e  of genetic  could  (Endler  force i n  1977).  In both  these  i s considered uniform  divergence  Cohan (1984) suggested t h a t i n  additivity,  i n phenotype  become  (1969)  t h a t gene flow and s e l e c t i o n  would cause more g e n e t i c  among i s o l a t e s .  that  differentiation  However, Cohan (1984) argued t h a t weak  of uniformity  alleles  faster  u n i f o r m i t y among p o p u l a t i o n s  o p e r a t i n g on f i n i t e p o p u l a t i o n s  than expected by g e n e t i c d r i f t  at  (Lynch  flow  t o s e t the degree o f divergence  r e f l e c t genetic uniformity.  traits  interest  More r e c e n t l y i t has been a p p r e c i a t e d  interact  selection  i s much  s e l e c t i o n , not gene flow,  approaches s e l e c t i o n f o r phenotypic to  spawners have  by i n t e r p o p u l a t i o n a l gene  argued t h a t uniform  may  The l a t e  among c o n s p e c i f i c p o p u l a t i o n s .  pressures  evolution.  development.  fixed  populations through  could  different  at a l t e r n a t i v e l o c i .  arrive genetic This  269  mechanism stocks  might  account  for  even though they  the  appear  incompatability  to possess  of  cross  a similar  matings  adaptation  to  of  late  season  of  spawning.  The flow  temporal  between  location  isolation  them.  generally  The  progeny of  show  fidelity  spawning but  a significant  times o f the  year.  genetic  isolate genetic  in  season  populations drift.  phenotypic  so  in  of  the  to the s e a s o n a l  among p o p u l a t i o n s .  The  key  do  estuary  meant  influence. in  that  effect  event d e t e r m i n i n g  promoting  uniformity  influence adult t r a i t s . c o u l d be  of  the  grounds.  The  wild  developing  under  phenotypes  were  phenotypes  quite quite  different different  r e a r e d under the same regime.  result  of m i g r a t i o n  fish  be  sufficient as  a  result  differences  to of on  with s e l e c t i o n  in genetic  may  could not  only  (1979) found t h a t age experienced  environmental the  1974).  among p o p u l a t i o n s  relatively  when  (Spieth  place  pressures  f r y phenotype  are  takes  other  divergence i n the  synchronous appearance of f r y on  selective  r e l a t e d t o the c o n d i t i o n s the  of  the p a t t e r n o f v a r i a t i o n  The  For example, H e l l e  season  prevent  environmental  may  and  enough to  selection to  gene  season  and  o f c l i m a t e coupled  locale  synchrony  high  appear  of  progression  common  Interpopulation  not  any  r e t u r n to spawn d u r i n g  of  divergence  r e s u l t s i s the t i m i n g of f r y emergence. the  location  i s potentially  absence  i n a given  in a particular  natal  s t r a y s may  genetic the  n e c e s s a r i l y preclude  spawning  their  reproduction  that  uniformity  to  gene flow  However,  development due for  In f a c t ,  does not  fish  number of  differentiation  Differences  of s t o c k s  similar  as  in  1  of  the  their  be  important  but  also  at  spite In  may  maturity  f r y on the  conditions.  embryos  exert  nursery  of  their  contrast,  populations  were  270  The the the  phenotypic  and g e n e t i c s t r u c t u r e o f chum salmon i s i n f l u e n c e d by both For example, Kubo ( 1 9 5 6 )  l o c a t i o n and season o f r e p r o d u c t i o n . mean  vertebral  This phenotypic separated  number  variation  by both  differed  was demonstrated  l o c a t i o n and season  autumn chum salmon o f the Amur phenotype  (Bakkala  1970).  not been confirmed.  If fisheries  River,  results  management  reproduction  may r e p r e s e n t  be managed s e p a r a t e l y chum salmon.  a genetic  o f spawning, differ  but t h e l o c a l e will  are a p p l i c a b l e must  to have  separated  such  greatly  t o a l l chum  different  production  basis.  Stocks  aspects  and  o f the  suggest t h a t when t h e  stocks  s t o c k s may  i n genotype.  salmon  with  units.  populations  different  then  seasons  I d e a l l y , these  of  should  This has been done f o r some time now i n  The p r a c t i s e d i d not have a c o n f i r m a t i o n  among the s t o c k s u n t i l t h i s work.  stocks.  b a s i s o f the d i f f e r e n c e s has  be d i v e r g e n t  that  ( L a r k i n 1981).  chum  o f spawning i s s i m i l a r ,  consider  that  as the summer  i n many  the r e s u l t s o f t h i s study  i n phenotype but s t i l l  these  spatially  However, the g e n e t i c  Finally,  season o f spawning d i f f e r s not d i v e r g e  among  noted  of genetic  divergence  271  LITERATURE CITED  Abakumov, V.A. 1961. I k h t i o l . No. 17.  Seasonal  races  o f diadrornous  fishes.  Vopr.  A l d e r d i c e , D.F., W.P. Wickett and J.R. B r e t t . 1958. Some e f f e c t s o f temporary exposure t o low d i s s o l v e d oxygen l e v e l s on P a c i f i c salmon eggs. J . F i s h . Res. Bd. Can. 15:229-250. Alexander, R.D. and R.S. Bigelow. 1960. A l l o c h r o n i c s p e c i a t i o n i n f i e l d c r i c k e t s and a new s p e c i e s , Acheta v e l e t i s . E v o l u t i o n 14: 334-346 A l l e n d o r f , K.W., K.L. Knudsen, R.F. L e a r y . 1983. Adaptive s i g n i f i c a n c e o f d i f f e r e n c e s i n t h e e x p r e s s i o n o f a phosphoglucomutase gene i n rainbow t r o u t . P r o c . N a t l . Acad. S c i . U.S.A. 80: 1397-1400. A l l e n d o r f , F.W. and F.M. U t t e r . 1979. P o p u l a t i o n g e n e t i c s p. 407-454. In W.S. Hoar, D.J. R a n d a l l and J.R. B r e t t [ e d . ] F i s h P h y s i o l o g y Academic Press, New York, N.Y. A l l e n d o r f , F.W., N. M i t c h e l l , N. Ryman, and G. S t a h l . 1977. Isozyme l o c i i n brown t r o u t (Salmo t r u t t a L.): d e t e c t i o n and i n t e r p r e t a t i o n from p o p u l a t i o n data H e r e d i t a s 86: 179-190. A l t u k o v , Yu.P. 1981. The s t o c k concept from the viewpoint genetics. Can. J . F i s h . Aquat. S c i . 38: 1523-1538.  of population  Altukov, Yu.P. and E.A. Salmenkova. 1981. A p p l i c a t i o n s o f the stock concept to f i s h p o p u l a t i o n s i n the U.S.S.R.. Can. J . F i s h . Aquat. S c i . 38: 1591-1600 Andersson, L., N. Ryman, R. Rosenberg and G. S t a h l . 1981. g e n e t i c v a r i a t i o n i n A t l a n t i c h e r r i n g (Clupea harengus L . ) : of isozyme l o c i and p o p u l a t i o n d a t a . H e r e d i t a s 95: 69-78.  Biochemical description  A r n o l d , S . J . 1986. L i m i t s on s t a b i l i z i n g , d i s r u p t i v e and c o r r e l a t i o n a l s e l e c t i o n s e t by t h e o p p o r t u n i t y f o r s e l e c t i o n Am. Nat. 128: 143-146. Aro,  K.V. and M.P. Shepard 1967. Salmon o f the North P a c i f i c Ocean - Part IV. Spawning p o p u l a t i o n s o f North P a c i f i c salmon. 5. P a c i f i c salmon i n Canada. I n t . N. Pac. F i s h . Comm., B u l l . 23: 225-327  A t c h l e y , W.R. 1987. Developmental q u a n t i t a t i v e g e n e t i c s and the e v o l u t i o n o f ontogenies. E v o l u t i o n 41: 316-330. A t k i n s o n , C.E., J.H. Rose, and T.0. Duncan. 1967. Salmon o f t h e North P a c i f i c Ocean - Part IV. Spawning p o p u l a t i o n s o f North P a c i f i c salmon. 4. P a c i f i c salmon i n t h e U n i t e d S t a t e s . I N t . N. Pac. F i s h . Comm., B u l l . 23: 43-223.  272  Bakkala, R.G. 1970. Synopsis o f B i o l o g i c a l Data on t h e Chum Salmon, Oncorhynchus keta (Walbaum) 1792. United S t a t e s Department o f the I n t e r i o r , U.S. F i s h and W i l d l i f e S e r v i c e , Bureau o f Commercial F i s h e r i e s , C i r c u l a r 315. B a i l e y , J . E . , S.D. R i c e , J . J . P e l l a and S.G. T a y l o r . 1980. Effects of s e e d i n g d e n s i t y o f p i n k salmon, Oncorhynchus gorbuscha, eggs on water c h e m i s t r y , f r y c h a r a c t e r i s t i c s , and f r y s u r v i v a l i n g r a v e l i n c u b a t o r s . F i s h e r y B u l l e t i n 78(3): 649-657. B a i l e y , J . E . and W.R. Heard. 1973. An improved i n c u b a t o r f o r salmonids and r e s u l t s o f p r e l i m i n a r y t e s t s o f i t s use. NOAA Tech. Memo, NMFS ABFL17p. B a i l e y , J.E., B.L. Wing and C R . Mattson. 1975. Zooplankton abundance and f e e d i n g h a b i t s o f f r y o f pink salmon, Oncorhynchus gorbuscha, and chum salmon, Oncorhynchus keta, i n T r a i t o r s Cove, A l a s k a , with s p e c u l a t i o n s on the c a r r y i n g c a p a c i t y o f the a r e a . F i s h . B u l l . 73(4): 846-861. Balon, E.K. 1979. The j u v e n i l i z a t i o n process i n phylogeny and the a l t r i c i a l to p r e c o c i a l forms i n t h e ontogeny o f f i s h e s . Env. B i o l . F i s h e s 4: 193-198. Bams, R.A. 1969. A d a p t a t i o n s i n sockeye salmon a s s o c i a t e d with i n c u b a t i o n i n stream g r a v e l s . Univ. B r i t i s h Columbia, H.R. M a c m i l l a n L e c t u r e s i n F i s h e r i e s , Symposium on salmon and t r o u t i n streams. T.G. N o r t h c o t e e d . pp. 71-88. Bams,  R.A. 1976. S u r v i v a l and p r o p e n s i t y f o r homing as a f f e c t e d by t h e presence o r absence o f l o c a l l y adapted p a t e r n a l genes i n two t r a n s p l a n t e d p o p u l a t i o n s o f pink salmon (Oncorhynchus g o r b u s c h a ) . J . F i s h . Res. Bd. Can. 33: 2716-2725.  Bams, R.A. 1982. E x p e r i m e n t a l i n c u b a t i o n o f chum salmon (Oncorhynchus keta) i n J a p a n e s e - s t y l e hatchery system. Can. Tech. Rep. F i s h , and A q u a t i c S c i . No. 1101: 65 p. Bams,  R.A. and K.S. Simpson 1977. Report on c u r r e n t s t a t e - o f - t h e - a r t . Rep. 689 68p.  Barlow, G.W. fishes. Bax,  Substrate incubators workshop-1976. Env. Canada, F i s h . Mar. S e r v . Tech.  1961. Causes and s i g n i f i c a n c e S y s t . Z o o l . 10: 105-117.  o f morphological  variation in  N.J. 1982. S e a s o n a l and annual v a r i a t i o n s i n t h e movement o f j u v e n i l e chum salmon through Hood Canal, Washington, p. 208-218. In Proc. Salmon and Trout M i g r a t o r y Behaviour Symposium. E.L. Brannon and E.0. S a l o ( e d s ) . Sch. o f F i s h . , Univ. Washington, S e a t t l e , WA.  273  Beacham, T.D. 1982. Fecundity o f coho salmon (Oncorhynchus k i s u t c h ) and chum salmon (CL keta) i n the n o r t h e a s t P a c i f i c Ocean. Can. J . Zool.60: 1463-1469. Beacham, T.D. Columbia.  1984. Age and morphology o f chum salmon T r a n s . Am. F i s h . Soc. 113 ( 6 ) : 727-736.  i n southern  Beacham, T.D. 1987. Genotype - environment i n t e r a c t i o n s i n growth salmon. Can. Tech. Rep. F i s h . Aquat. S c i . (1517).  British  o f chum  Beacham, T.D., A.P. Gould, R.E. W i t h l e r , C.B. Murray, and L.W. Barner. 1987. Biochemical genetic survey and s t o c k identification o f chum salmon (Oncorhynchus keta) i n B r i t i s h Columbia. Can. J . F i s h . Aquat. S c i . 44: 1702-1713. Beacham, T.D. and C.B. Murray 1985. E f f e c t o f female s i z e , egg s i z e , and water temperature on the developmental biology of chum salmon (Oncorhynchus keta) from the N i t i n a t R i v e r , B r i t i s h Columbia. Can. J . F i s h . Aquat. S c i . 42: 1755-1765. Beacham, T.D. and C.B. Murray 1986. Comparative developmental b i o l o g y o f chum salmon (Oncorhynchus keta) from the E r a s e r R i v e r , B r i t i s h Columbia. Can. J o u r n a l F i s h . Aquat. S c i . 4 3 ( 2 ) : 252-262. Beacham, T.D. and P. S t a r r . 1982. P o p u l a t i o n b i o l o g y o f chum Oncorhynchus k e t a , from the F r a s e r R i v e r , B r i t i s h Columbia. S t a t e s N a t i o n a l Marine S e r v i c e F i s h e r y B u l l e t i n 80: 813-825.  salmon, United  Beacham, T.D., and C.B. Murray, 1986b. The e f f e c t o f spawning time and i n c u b a t i o n temperature on m e r i s t i c v a r i a t i o n i n chum salmon (Oncorhynchus keta). Can. J . Z o o l . 64: 45-48. Beacham, T.D., and C.B Murray. 1987a. A d a p t i v e v a r i a t i o n i n body s i z e , morphology, egg size, and developmental biology o f chum salmon (Oncorhynchus keta) i n B r i t i s h Columbia. Can. J . F i s h . Aquat. S c i . 44: 244-261. Beacham, T.D., and C.B. Murray. 1987b. E f f e c t s o f t r a n s f e r r i n g pink (Oncorhynchus gorbuscha) and chum (Oncorhynchus keta) salmon embryos a t d i f f e r e n t developmental s t a g e s t o a low i n c u b a t i o n temperature. Can. J . Z o o l . 65: 96-105. Beacham, T.D. and P. S t a r r . 1982. P o p u l a t i o n b i o l o g y o f chum Oncorhynchus keta, from t h e F r a s e r R i v e r , B r i t i s h Columbia. S t a t e s N a t i o n a l Marine S e r v i c e F i s h e r y B u l l e t i n 80: 813-825.  salmon, United  Beacham, T.D. and R.E. W i t h l e r . 1987. Developmental stability and heterozygosity i n chum (Oncorhynchus keta) and Pink (Oncorhynchus gorbuscha) salmon. Can. J . Z o o l . 65: 1823-1826.  274  Beacham, T.D., R.E. W i t h l e r , and A.P. Gould. 1985. Biochemical genetic stock i d e n t i f i c a t i o n o f chum salmon (Oncorhynchus keta) i n southern B r i t i s h Columbia. Can. J . F i s h . Aquat. S c i . 42: 437-448. Becker, W. 1975. A manual o f q u a n t i t a t i v e Pullman, Wash.  g e n e t i c s . 3rd. Ed. Wash St. Univ.,  Bengtson, D.A., R.C. Barkman and W.J. Berry. 1987. R e l a t i o n s h i p between maternal s i z e , egg diameter, time o f spawning season, temperature, and l e n g t h at hatch o f a t l a n t i c s i l v e r s i d e , Menidia medidia. J. Fish. B i o l . 31: 697-704. Berg, L.S. 1934. Yarovye i ozimye rasy u prokhodnykh r y b . I z v e s t i i a Akademii Nauk SSSR, O t d e l Matematicheskish i E s t e s t v e n n y k h Nauk 5: 711-732. Berg,  L.S. 1959. V e r n a l and heimal r a c e s among T r a n s l a t i o n i n J . F i s h . Res. Bd. Can. 16: 515-537.  anadromous  fishes.  B i e t t e , R.M., D.P. Dodge, R.L. Hassinger and T.M. Stauffer. 1981. Life h i s t o r y and t i m i n g o f m i g r a t i o n s and spawning behaviour o f rainbow t r o u t (Salmo g a i r d n e r i ) p o p u l a t i o n s o f the Great Lakes. Can. J . F i s h . Aquat. S c i . 38: 1759-1771. B i l t o n , H.T. 1980. Returns o f a d u l t coho salmon i n r e l a t i o n t o mean s i z e and time o f r e l e a s e o f j u v e n i l e s t o the c a t c h and the escapement. Can. Rep. F i s h . Aquat. S c i . 941. Birman, I.B. 1956. L o c a l s t o c k s o f autumn F i s h . Res. Bd. Can. T r a n s l . Ser. 349.  chum salmon  i n the Amur B a s i n .  Birman, I.B. 1959. More about the i n f l u e n c e o f the K u r i o - s h i o on the dynamics o f abundance o f salmon. F i s h . Res. Bd. Can. T r a n s l . Ser. 269. Birman, I.B. 1977. I n t r a p o p u l a t i o n groupings o f the Amur Autumn chum Oncorhynchus k e t a . J . I c h t h y o l . 17: 741-750. Birman, I.B. 1981. Ocean m i g r a t i o n and o r i g i n o f s e a s o n a l anadromous salmon (Salmonidae). J . I c h t h y o l . 21: 35-47. B l a i r , W.F. 1941. c e r t a i n toads.  Variation, isolating G e n e t i c s 26: 398-417.  mechanisms,  and  salmon,  races  of  hybridization  in  B l a x t e r , J.H.S. 1958. R a c i a l problem i n h e r r i n g from the viewpoint o f r e c e n t p h y s i o l o g i c a l , e v o l u t i o n a r y and g e n e t i c a l t h e o r y . Rapp. Cons. E x p l o r . Mer. 143(2): 10-19. Brannon, E.L. 1982. O r i e n t a t i o n mechanisms o f homing Brannon and E.O. Salo (eds). Salmon and t r o u t symposium, Univ. Wash., S e a t t l e . 219-227.  salmonids. In E.L. m i g r a t o r y behaviour  275  Brannon, E.L. 1984. Influence of stock origin on salmon migratory behaviour. IN Mechanisms of m i g r a t i o n i n f i s h e s . McCleave, J.D., G.P. A r n o l d , J . J . Dodson and W.H. N e i l l . ( e d s ) . NATO Conference S e r i e s , V o l . 14: 103-112. B u k l i s , L.S. 1982. Anvik, Andreafsky and Tanana R i v e r salmon escapement studies. 1981. Yukon Salmon Escapement Report No. 15. Alaska Dept. F i s h Game, Commercial F i s h e r i e s D i v i s i o n , Anchorage, A l a s k a . 40p. B u k l i s , L.S. and L.H. Barton. 1984. Yukon R i v e r chum salmon s t o c k s t a t u s . A l a s k a Dept. F i s h Game Info L e a f l e t No. 239. Bull, Bull,  J.J.  1987.  E v o l u t i o n o f phenotypic  J . J . , C. Thompson, D. Ng and s e l e c t i o n of genetic migration.  biology 67p.  variance E v o l u t i o n 41(2):  R. Moore. 1987. A model Am. Nat. 129: 143-157.  and  303-315.  for natural  Bush, G.L. 1974. The mechanism o f sympatric host race formation i n the t r u e fruit files (Tephritidae). In Genetic mechanisms o f s p e c i a t i o n i n insects. M.J.D. White ( e d ) , Sydney, A u s t r a l i a and New Zealand Book Co. pp. 3-23. Bush, G.L. 1975. 339-364.  Modes of animal  speciation.  Ann.  Rev.  E c o l . Systemat.  6:  Burger, C.V., R.L. Wilmot, and D.B. Wangaard. 1985. Comparison o f spawning areas and times f o r two runs o f chinook salmon (Oncorhynchus tshawytscha) i n the Kenai R i v e r , A l a s k a . Can. J . F i s h . Aquat. S c i . 42: 693-700. Burner, C.J. salmon.  1951. C h a r a c t e r i s t i c s of spawning nests o f Columbia U.S. F i s h and W i l d l i f e S e r v i c e F i s h e r y B u l l . 52: 97-110.  River  Calaprice, J. 1969. P r o d u c t i o n and g e n e t i c f a c t o r s i n managed salmonid p o p u l a t i o n s In Symp. on salmon and t r o u t i n streams T.G. Northcote (ed) 377-385. Carson, H.L. and A.R. Templeton. 1984. G e n e t i c r e v o l u t i o n s i n r e l a t i o n to s p e c i a t i o n phenomena: The founding o f new p o p u l a t i o n s . Ann. Rev. E c o l . S y s t . 15: 97-131. C a v a l l i - S f o r z a , L.L. 1969. Am. 221: 30-37.  "Genetic  drift"  i n an  Italian  population.  C a v a l l i - S f o r z a , L.L. and A.W.F. Edwards. 1967. Phylogenetic and e s t i m a t i o n procedures. E v o l u t i o n 21: 550-570. Chatwin, B.M. 1953. 1950. F i s h . Res.  Tagging o f chum salmon i n Johnstone Bd. Can. B u l l . 96, 33 p.  Chebanov, N.A. 1986. I c h t h y o l . 26(3):  F a c t o r s c o n t r o l i n g spawning success 69-78.  Sci.  a n a l y s i s models  Strait,  i n pink  1945  salmon  and  T.  276  C h i a r e l l o , N. and J . Roughgarden. of an annual p l a n t : o p t i m a l 1290-1301.  1984. Storage a l l o c a t i o n i n seasonal races versus a c t u a l a l l o c a t i o n . Ecology 6 5 ( 4 ) :  C h i l c o t e , M.W., S.A. L e i d e r and J . J . Loch. 1986. D i f f e r e n t i a l reproductive success of hatchery and wild summer-run steelhead under natural conditions. Trans. Am. F i s h . Soc. 115: 726-735. C h i l d , A.R. 1980. E l e c t r o p h o r e t i c a n a l y s i s o f A r t i e char o f cambrian l a k e s . In p r o c e e d i n g s of the f i r s t ISACF workshop on a r t i c c h a r r . Institute Freshwater Research, Drottningholm (Sweden) ( E d ) : 5-8. C h i l t o n , D.E. and R.J. Beamish. 1982. Age d e t e r m i n a t i o n methods f o r f i s h e s s t u d i e d by the G r o u n d f i s h Program at the P a c i f i c B i o l o g i c a l S t a t i o n . Can. Spec. P u b l . F i s h . Aquat. S c i . 60. 102 p. Chugunova, N.I. 1959. C l e a r i n g h o u s e Fed. 164 pages.  Age and growth s t u d i e s i n f i s h . T r a n s l . TT61-31036, S c i . Tech. Inform., S p r i n g f i e l d , Va., U.S.A. 22151.  Clayton, J. 1981. The s t o c k concept and the u n c o u p l i n g o f organismal m o l e c u l a r e v o l u t i o n . Can. J . F i s h . Aquat. S c i . 38: 1515-1522. Clemens, W.A. and G.V. Wilby. 1946. F i s h e s o f the F i s h . Res. Bd. Can., B u l l . 68, 368 p.  of  Canada.  Cohan, F.M. 1984. Can uniform s e l e c t i o n r e t a r d g e n e t i c divergence i s o l a t e d c o n s p e c i f i c p o p u l a t i o n s ? E v o l u t i o n 38: 495-504.  between  Cole,  L.C. 1954. Q u a r t e r l y Rev.  The p o p u l a t i o n consequences B i o l . 29: 103-137.  of  Pacific  life  coast  and  history  phenomena.  Congleton, J.L. 1978. Feeding p a t t e r n s o f j u v e n i l e chum i n the S k a g i t R i v e r s a l t marsh, p. 141-150. In Proc. Second Northwest Tech. Workshop o f F i s h and Food Habit S t u d i e s , S.J. Lipovsky and C A . Simenstad ( e d s ) . Wash. Sea. G r a n t . Univ. Washington, S e a t t l e , WA. Danzmaan, R.G., M.M. Ferguson, and F.W. h e t e r o z y g o s i t y i n f l u e n c e developmental 56(3): 417-425. D i c k i n s o n , H. and J . Antonovics. sympatric d i v e r g e n c e . Am. Nat. Dill,  Allendorf. 1986. Does enzyme r a t e i n rainbown t r o u t ? H e r e d i t y ,  1973. Theoretical 107: 256-274.  considerations  of  L.M. and T.G. N o r t h c o t e . 1970. E f f e c t s o f g r a v e l s i z e , egg depth and egg d e n s i t y on intra-gravel movement and emergence i n coho salmon (Oncorhynchus k i s u t c h ) a l e v i n s . J . F i s h . Res. Board Can. 27: 1191-1199.  Dowling, T.E. and W.S. Moore. 1985. Evidence f o r s e l e c t i o n a g a i n s t h y b r i d s in the f a m i l y C y p r i n i d a e (genus N o t r o p i s ) . E v o l u t i o n 39: 152-158.  277  Dunnett, C.W. 1980. Pairwise unequal sample s i z e case.  m u l t i p l e comparisons i n homogeneous J. Amer. S t a t . Assoc. 75: 789-795.  Ehrman, L. 1970. The mating advantage of N a t l . Acad. S c i . U.S.A. 515: 345-348.  r a r e males  variance,  in Drosophila.  Proc.  E l s o n , M.S. 1975. Enumeration o f spawning chum salmon (Oncorhynchus keta) i n the F i s h i n g Branch River i n 1971, 1972, 1973 and 1974. IN: Northern Yukon F i s h e r i e s S t u d i e s , 1971-1974, V o l . 1, Chapter I I . Steigenberger, L.W., M.S. E l s o n and R.T. Delury. eds. Northern Oper. Branch, F i s h Mar. Serv. Dept. E n v i r o n . Can., PAC/T-75-19 45p. E n d l e r , J.A. 1977. Geographic U n i v . P r e s s , P r i n c e t o n , New  V a r i a t i o n , S p e c i a t i o n and J e r s e y . 239p.  E n d l e r , J.A. 1986. Natural P r i n c e t o n 126 p.  s e l e c t i o n i n the  E r l i c h , P.R. and P.H. 165: 1228-1232.  1969.  Raven.  wild.  Differentiation  Clines.  Princeton  Princeton  Univ.  of populations.  Press,  Science  E v e l y n , T.P.T., J.E. Ketcheson, L. P r o s p e r i p o r t a . 1986. Use of erythromycin as a means of preventing vertical transmission of Renibacterium salmoninarum. D i s t . Aquat. Org. 2 ( 1 ) : 7-11. F a l c o n e r , D.S. F a r r i s , J.S. Am. Nat. F a r r i s , J.S. 83-92.  1981.  I n t r o d u c t i o n to q u a n t i t a t i v e g e n e t i c s .  1972. Estimating 106: 645-668. 1970.  Methods  for  phylogenetic  computing  trees  Wagner  from  trees.  Longman,  distance  Syst.  N.Y.  matrices.  Zool.  19:  F a r r i s , J.S. 1981. D i s t a n c e data i n p h y l o g e n e t i c a n a l y s i s . In V.A. Funk and D.R. Brooks ( e d s ) . Advances i n c l a d i s t i c s ; proceedings of the first meeting o f the W i l l i e Hennig S o c i e t y . New York, NY pp 3-23. F a s t , D.E. and Q.J. S t o b e r . 1984. I n t r a g r a v e l behavior of salmonid a l e v i n s i n response t o environmental changes. F i n a l Report for Wash. Water Research Center and C i t y o f S e a t t l e , S e a t t l e , WA. FRI-UW-8414:103 p. Ferguson, A. 1980. Electrophoretic analysis of tissue proteins for char. In Proceedings of the f i r s t ISACF workshop on A r t i e c h a r r . Freshwater Research, Drottningholm, Sweden pp. 12-13. F i s h e r , R.A. York.  1930.  The  g e n e t i c a l theory  of natural s e l e c t i o n .  Fowler, J.A. 1970. C o n t r o l o f v e r t e b r a l number i n t e l e o s t s - an problem. Quart. Rev. B i o l . 45: 148-167.  Irish Inst.  Dover,  New  embrological  278  F r e s h , K.L., R.D. C a r d w e l l , B.P. Snyder and E.O. S a l o . 1982. Some hatchery s t r a t e g i e s f o r r e d u c i n g p r e d a t i o n upon j u v e n i l e chum salmon (Oncorhynchus keta) i n f r e s h w a t e r . IN Proceedings o f t h e North P a c i f i c Aquaculture Symposium. B.R. M e l t e f f and R.A. Neve ( e d s ) . Alaska Sea Grant Rep., A l a s k a Sea Grant Program, A l a s k a Univ. pp. 79-89. Fresh, K.L. and S. Schroder. 1987. I n f l u e n c e o f abundance, s i z e , and y o l k r e s e r v e s o f j u v e n i l e chum salmon (Oncorhynchus keta) on p r e d a t i o n by freshwater f i s h e s i n a s m a l l c o a s t a l stream. Can. J . F i s h . Aquat. S c i . 44: 236-243. Frolenko, L.A. 1970. Feeding o f chum and pink salmon j u v e n i l e s m i g r a t i n g downstream i n t h e main spawning r i v e r s o f the n o r t h e r n c o a s t o f t h e Sea o f Okhotsk. F i s h . Res. Bd. T r a n s l . S e r . 2416. F r o s t , W.E. 1966. Breeding h a b i t s o f Windermere c h a r , S a l v e l i n u s w i l l u g h b i i (Gunther), and t h e i r b e a r i n g on s p e c i a t i o n o f these f i s h . Proc. Royal soc. s e r i e s B: 232-284. Frydenburg, 0., D. M o l l e r , G. Naevdal, and K. S i c k . 1965. Haemoglobin polymorphism i n Norwegian cod p o p u l a t i o n s . H e r e d i t a s 53: 257-271. Futuyma, D.J. 1979. Mass. 565 p.  Evolutionary biology.  Siriauer Assoc.,  Inc. Sunderland,  G a b r i e l , K.R. 1964. A procedure f o r t e s t i n g the homogeneity o f a l l s e t s o f means i n a n a l y s i s o f v a r i a n c e . B i o m e t r i c s 20: 459-477. G a d g i l , M. and W.H. Bossert 1970. L i f e selection. Amer. Natur. 104: 1-24.  historical  consequences o f n a t u r a l  Gall,  G.A.E. 1974. I n f l u e n c e o f s i z e o f eggs and age o f female on h a t c h a b i l i t y and growth i n rainbow t r o u t . C a l i f . Dep. F i s h Game 00(1): 26-35.  Gall,  G.A.E. 1975. G e n e t i c s o f r e p r o d u c t i o n J. Animal S c i . 40(1): 19-27.  Gall,  G.A.E., J . Baltodana, and N. Huang. 1988. Heritability spawning f o r Rainbow t r o u t Aquaculture 68: 93-102.  Gerking, 13:  S.D. 1988. . F i s h e r y b i o l o g y : 13-17.  i n domesticated  Past, present  rainbow t r o u t .  and f u t u r e .  o f age at  Fisheries  G i l b e r t , C H . and W.H. R i c h . 1927. I n v e s t i g a t i o n s c o n c e r n i n g t h e red-salmon runs t o the Karluk R i v e r , A l a s k a . U.S. Bur. F i s h . B u l l . 43: 1-69. Gjedrem, T. 1976. P o s s i b l i t i e s of genetic F i s h . Res. Board. Can. 33: 1094-1099.  improvement  i n salmonids.  J.  279  Gjedrem, T. 1983. Genetic v a r i a t i o n in q u a n t i t a t i v e t r a i t s b r e e d i n g i n f i s h and s h e l l f i s h . Aquaculture 33: 51-72.  and  selective  G r i g o , L.D. 1953. M o r p h o l o g i c a l d i f f e r e n c e s between summer and autumn chum salmon Oncorhynchus keta (Walbaum) and 0. keta (Walbaum) i n f r a s p e c i e s autumnalis Berg. IN " P a c i f i c salmon: s e l e c t e d a r t i c l e s from S o v i e t periodicals. Clearinghouse Fed. S c i . Tech. Inform., S p r i n g f i e l d , Va. 22151. Godin, J-G.J. 1982. M i g r a t i o n s o f salmonid f i s h e s d u r i n g e a r l y l i f e h i s t o r y phases: daily and annual timing. IN: Salmon and trout migratory behaviour symposium. E.L. Brannon and E.O. S a l o , eds. U. Wash., Seattle, pp. 22-50. Gould, S.J. 1982. Change i n developmental t i m i n g as a macroevolution. IN. E v o l u t i o n and Development. J.T. S p r i n g e r - V e r l a g , New York, NY. Gould, S.J. 1982. P a l e o b i o l o g y 6:  Is a new 119-130.  Gould, S.J. and N. E l d r i d g e . evolution reconsidered.  and  general  theory  of  mechanism o f Bonner ( e d ) .  evolution  1977. Punctuated e q u i l i b r i a : P a l e o b i o l o g y 3: 115- 151.  emerging?  tempo and mode o f  Groot, C , T.P. Quinn, and T . J . Hara. 1986. Response o f m i g r a t i n g sockeye salmon (Oncorhynchus nerka) t o p o p u l a t i o n - s p e c i f i c odours. J. Z o o l . 64: 926-932.  adult Can.  Grotnes, P. 1980. P l a s t i c i t y o f char p o p u l a t i o n s t r u c t u r e s and the char complex. In Proceedings o f the f i r s t ISACF workshop on A r t i e c h a r . I n s t i t u t e Freshwater Research, Drottningholm (Sweden): 14. Gunnes, K., and T. Gjedrem. 1978. S e l e c t i o n experiments with salmon. Growth o f A t l a n t i c salmon d u r i n g two years i n the s e a . Aquaculture 19-33. G u s t a f f s o n , L. 1986. E m p i r i c a l support 761-764. H a r r i s , H. 1966. 298-310. H a r l a n , J.R. 1981. 1459-1463.  Lifetime reproductive f o r F i s h e r ' s fundamental  Enzyme polymorphisms i n man.  Who's i n charge  here.  IV 15:  s u c c e s s and heritability: theorem. Am. Nat. 128:  P r o c . Roy.  Can.  J. Fish.  Soc.  Land.  B164:  Aquat. S c i . 38:  Harrison, R.G. 1985. B a r r i e r s to gene exchange among c l o s e l y r e l a t e d cricket species. II. Life cycle variation and temporal isolation. E v o l u t i o n 39(2): 244-259.  280  H a r t l , D. 1980. P r i n c i p l e s of population g e n e t i c s . Sunderland, Mass. 488 p. H a r t l , D. 1981. A Primer o f P o p u l a t i o n G e n e t i c s . Sunderland, Mass. 191p.  S i n a u e r Assoc.  Inc.,  S i n a u e r and Assoc. Inc.,  H a r t t , A.C. 1980. J u v e n i l e salmonids i n the o c e a n i c ecosystem - the c r i t i c a l f i r s t summer, p. 25-58. In Salmonid Ecosystems o f the North P a c i f i c . W.J. McNeil and D.L. Himsworth ( e d s ) . Oregon S t . U n i v . P r e s s , C o r v a l l i s , OR. H a s l e r , A.D. 1954. Odour p e r c e p t i o n and Res. Bd. Can. 11(2): 107-128.  orientation  in fishes.  J.  Fish.  Healey, M.C. 1978. The d i s t r i b u t i o n , abundance, and f e e d i n g h a b i t s o f j u v e n i l e P a c i f i c salmon i n Georgia S t r a i t , B r i t i s h Columbia. F i s h . Mar. Serv. Tech. Rep. 788. 49 p. Healey, M.C. 1979. D e t r i t u s and j u v e n i l e salmon p r o d u c t i o n i n the Nanaimo Estuary: I. P r o d u c t i o n and feeding rates of juvenile chum salmon (Oncorhynchus k e t a ) . J . F i s h . Res. Board Can. 36: 488-496. Healey, M.C. 1980. The e c o l o g y o f j u v e n i l e salmon i n G e o r g i a S t r a i t , B r i t i s h Columbia, p. 203-229. Insalmonid ecosystems o f the North P a c i f i c . W.J. McNeil and D.C. Himsworth ( e d s . ) . Oregon S t . U n i v . P r e s s . C o r v a l l i s , OR. Healey, M.C. 1982. Timing and r e l a t i v e i n t e n s i t y o f s i z e - s e l e c t i v e m o r t a l i t y of j u v e n i l e chum salmon (Oncorhynchus keta) d u r i n g e a r l y sea l i f e . Can. J . F i s h , and Aquat. S c i . 39: 952-957. Healey, M.C. 1983. Coastwide d i s t r i b u t i o n and streamand ocean-type Chinook salmon, Canadian F i e l d - N a t u r a l i s t 97(4):427-433.  ocean m i g r a t i o n p a t t e r n s o f Oncorhynchus tshawytscha.  H e l l e , J.H. 1979. I n f l u e n c e o f marine environment on age and s i z e at maturity, growth, and abundance o f chum salmon, Oncorhynchus k e t a (Walbaum), from Olsen Creek, P r i n c e W i l l i a m Sound, A l a s k a . Ph.D. T h e s i s , Oregon S t a t e U n i v e r s i t y . 118p. Helle, J.H. 1981. Significance o f the s t o c k concept in artificial p r o p a g a t i o n o f salmonids i n A l a s k a . Can. J . F i s h . Aquat. S c i . 38: 1665-1671. Hitchcock, C L . and A. C r o n q u i s t . 1973. F l o r a o f the U n i v e r s i t y o f Washington. S e a t t l e and London. 730 p.  Pacific  Northwest.  Hoar, W.S. 1958. The e v o l u t i o n o f m i g r a t o r y behaviour among j u v e n i l e salmon of the genus Oncorhynchus. J . F i s h . Res. Bd. Can. 15: 391-428. Hochberg, Y. inference.  1976. A modification o f the J . M u l t i v a r . A n a l . 4: 224-234.  T-method  in  simultaneous  281  Hubbs, C.L. and K.F. L a g l e r . 1958. F i s h e s o f the Great Lakes Region. Mich. P r e s s , Ann Arbor, Mich. 213 p. Hunter, J.G. 1959. c o a s t a l stream.  S u r v i v a l and p r o d u c t i o n o f pink and J . F i s h . Res. Bd. Can. 16: 835-886.  Univ.  chum salmon  H u r l b e r t , S.H. 1984. P s e u d o r e p l i c a t i o n and the d e s i g n o f e c o l o g i c a l experiments. E c o l o g i c a l Monographs 54(2): 187-211. H u t c h i s o n , G.E. 1959. k i n d s o f animals.  Homage t o Santa R o s a l i a , Am. Nat. 93: 145-159.  Hynes, H.B.N. 1976. The Ecology o f Press, Waterloo, O n t a r i o . 526p.  Running  or  Waters.  why  are  there  Waterloo  Ihssen, P.E. 1976. S e l e c t i v e b r e e d i n g and h y b r i d i z a t i o n management. J . F i s h . Res. Board Can. 33: 316-321.  in a  field  so many  University  in  fisheries  Ihssen, P.E., H.E. Booke, J.M. Casselman, J.M. McGlade, N.R. Payne, and F.M. Utter. 1981. Stock i d e n t i f i c a t i o n : m a t e r i a l s and methods. Can. J . F i s h . Aquat. S c i . 38(12): 1838-1855. I r i e , T. 1982. M i g r a t i o n and ecology o f young salamon i n t h e i r e a r l y life. 11th UJNR A q u a c u l t u r e P a n e l , 1982, Tokyo, Japan. 17 p.  marine  Ivankov, V.N. 1967. On s e a s o n a l r a c e s o f pink salmon. Izv. Tikhook. n . - i . i n - t a rybn. kh-va i okeanogr., 61. - 1968. The P a c i f i c salmon o f Iturup Island ( K u r i l I s l a n d s ) . I z v . Tikhookeansk. n.- i . i n - t a rybn. kh-va i okeanogr., 65. Iwamoto, R.N., E.O. S a l o , M.A. Madej, and R.L. McComas. 1978. Sediment and water q u a l i t y : a review o f the l i t e r a t u r e i n c l u d i n g a suggested approach for water q u a l i t y c r i t e r i a ; with Summary o f Workshop c o n c l u s i o n s and recommendations, by E.O. S a l o and R.L. R u l i f s o n . The U.S. Environmantal P r o t e c t i o n Agency, Reg. 10, EPA 910/9-78-048: 150 p. Iwata, M. salmon Symp., 82-83.  1982. Downstream m i g r a t i o n and seawater a d a p t a b i l i t y o f chum (Oncorhynchus keta) f r y , p. 51-59. In Proc. No. Pac. A q u a c u l t u r e Aug. 1980, Anchorage, Ak. Univ. A l a s k a , A l a s k a Sea Grant Rep.  Jensen, H.M. 1956. R e c o v e r i e s o f immature chum salmon tagged Puget Sound. Wash. Dept. F i s h . , F i s h . Res. papers 1(4):32.  in  southern  Jensen, J . and D. A l d e r d i c e . 1983. Changes i n mechanical shock s e n s i t i v i t y of coho salmon (Oncorhynchus kisutch) eggs during incubation. A q u a c u l t u r e 32: 303-312. K a p u s c i n s k i , A.R.D. and J.E. Lannan 1986. A c o n c e p t u a l f i t n e s s model f o r f i s h e r i e s management. Can. J . F i s h . Aquat. S c i . 4 3 ( 8 ) : 1606-1616.  282  Katayama, M. 1935. Biometric study o f dog salmon (Oncorhynchus (Walbaum)). B u l l . Jap. Soc. S c i . F i s h . 4: 171-173. Transl. Commer. F i s h . , B i o l . Lab., S e a t t l e , Wash., T r a n s l . S e r . 1. K e t t l e w e l l , H.B.D. 1956. Further s e l e c t i o n experiments melanism i n the L e p i d o p t e r a . H e r e d i t y 10: 287-301. Killick, S. 1955. The c h r o n o l o g i c a l order of salmonduring m i g r a t i o n , spawning and death. Salmon F i s h e r i e s Commission B u l l e t i n 7. Kimura, S. 1981. Kyushu. Jap.  on  industrial  Fraser River International  Records o f chum salmon, Oncorhynchus k e t a J . I c h t h y o l . 28(2): 193-196.  Kneib, R.T. 1987. P r e d a t i o n r i s k and use of i n t e r t i d a l F i s h e s and shrimp. Ecology 68(2): 379-386.  keta Bur.  from  sockeye Pacific  northern  h a b i t a t s by  young  Kobayashi, T. 1960. An e c o l o g i c a l study o f the salmon f r y , Oncorhynchus keta (Walbaum). VI. Note on the f e e d i n g a c t i v i t y of chum salmon f r y . Bull. Jpn. Soc. S c i . F i s h . 26: 577-580 ( E n g l i s h A b s t r . ) Kobayashi, T. and Y. Ishikawa. 1964. An e c o l o g i c a l study on the salmon f r y , Oncorhynchus keta (Walbaum) - V I I I . The growth and f e e d i n g h a b i t of the f r y d u r i n g seaward m i g r a t i o n . S c i . Rep. Hokkaido Salmon Hatch. 18: 7-15. Koo,  T.S.Y. 1962. Age d e s i g n a t i o n i n salmon. p. 37-48. In T.S.Y. ( e d . ) , S t u d i e s o f A l a s k a red salmon. U n i v . Wash. P r e s s , S e a t t l e .  Koo  K o s k i , K.V. 1975. The s u r v i v a l and f i t n e s s o f two s t o c k s o f chum salmon (Oncorhynchus keta) from egg deposition to emergence in a controlled-stream environment. Ph.D. Thesis, Univ. Wash., S e a t t l e , Wash. 212p. Kostarev, V.L. Board. Can  1973. V a r i a t i o n of s u r v i v a l T r a n s l . S e r . 2536: 1-16.  of  Okhotsk  keta.  Fish.  Res.  K r o g i u s , F.V., V.S. Bool and A.S. Baranenkova. 1934. A note on the b i o l o g y o f the salmonid f i s h e s o f Kamchatka. B y u l . Kamchatskogo O t d e l TINRO, No.1. Kubo,  T. 1950. A preliminary report of the study on the groups o f Oncorhynchus keta (Walbaum) (dog salmon) and the numbers of their segments. B u l l . Fac. F i s h e r i e s , Hokkaido Univ., 1 ( 1 ) : 1-11  Kubo, T. 1956. P e c u l i a r i t y o f p o p u l a t i o n o f chum salmon i n the S h u r i u c h i R i v e r i n r e s p e c t to v e r t e b r a l count. B u l l . Fac. F i s h e r i e s Hokkaido Univ., 6 ( 4 ) : 266-270. U.S. F i s h W i l d l i f e Serv., T r a n s l a t i o n No. 12 . K u l i k o v a , N.I. 1971. I n t r a s p e c i f i c v a r i a b i l i t y o f karyotype o f salmon (Oncorhynchus keta (Walb.)). J . I c h t h y o l . 11: 977-983.  the  chum  283  Lalanne, J . J . B u l l . 27:  1971. 91p.  Marine growth  o f chum, salmon.  I n t . N. Pac. F i s h . Comm.  Lande, R. 1975. The maintenance o f gametic v a r i a b i l i t y by mutation p o l y g e n i c c h a r a c t e r with l i n k e d l o c i . Genet. Res. 26: 221-235.  in a  L a r k i n , P.A. 1972. The s t o c k concept and management o f P a c i f i c salmon. Univ. B r i t i s h Columbia, H.R. M a c M i l l a n L e c t u r e s , The stock concept i n P a c i f i c salmon. 11-15. Larkin, P.A. 1981. A p e r s p e c t i v e on p o p u l a t i o n g e n e t i c s management. Can. J . F i s h . Aquat. S c i . 38(12): 1469-1475.  and  salmon  Leary, R.F., F.W. A l l e n d o r f and K.L. Knudsen. 1985. I n h e r i t a n c e of m e r i s t i c v a r i a t i o n and the e v o l u t i o n o f developmental s t a b i l i t y i n rainbow t r o u t . E v o l u t i o n 3 9 ( 2 ) : 308-314. L e i d e r , S.A., M.W. C h i l c o t e , and J . J . Loch. 1984. Spawning c h a r a c t e r i s t i c s o f s y m p a t r i c p o p u l a t i o n s o f s t e e l h e a d t r o u t (Salmo g a i r d n e r i ) : evidence for p a r t i a l reproductive i s o l a t i o n . Can. J . F i s h . Aquat. S c i . 41: 1454-1462. L e i d e r , S.A., M.W. C h i l c o t e , J . J . Loch. 1986. Comparative l i f e h i s t o r y c h a r a c t e r i s t i c s o f h a t c h e r y and w i l d s t e e l h e a d t r o u t (Salmo g a i r d n e r i ) o f summer and w i n t e r r a c e s i n the Kalama r i v e r , Washington. Can. J . F i s h . Aquat. S c i . 4 3 ( 7 ) : 1398-1409. Lewontin, R.C. and J.L. Hubby. 1966. A m o l e c u l a r approach to the study o f genie heterozygosity in natural populations of Drosophila pseudo-obscura. G e n e t i c s 54: 595-609. L e v i n s , R. 1963. Theory o f f i t n e s s i n a heterogeneous environment Developmental f l e x i b i l i t y and n i c h e s e l e c t i o n . Am. Nat. 97: 75-90. Levy,  II.  D.A. and T.G. Northcote 1981. The d i s t r i b u t i o n and abundance o f j u v e n i l e salmon i n marsh h a b i t a t s o f the F r a s e r R i v e r E s t u a r y . Univ. B r i t i s h Columbia Tech. Report No. 25, Vancouver, B.C.  L i n d e n f e l s e r , M.E. 1984. Morphometric and a l l o z y m i c congruence: Evolution in the prawn, Macrobrachium rosenbergii (Decapoda: Palaemonidae). S y s t . Z o o l . 3 3 ( 2 ) : 195-204. Lindsey, C C . 1975. Pleomerism, the widespread tendency among r e l a t e d f i s h s p e c i e s f o r v e r t e b r a l number t o be c o r r e l a t e d w i t h maximum body l e n g t h . J . F i s h . Res. Board Can. 32: 2453-2469. Lindsey, C C 1988. XIB: 197-274.  Factors c o n t r o l l i n g meristic v a r i a t i o n .  Fish  physiology  Lindsey, C C , A.M. B r e t t , D.P. Swain. 1984. Responses o f v e r t e b r a l numbers i n rainbow t r o u t to temperature changes d u r i n g development Can. J . Z o o l . •62(3): 391-396.  284  L i n d s e y , C C . and A.N. Arnason. 1981. A model f o r repsonses o f v e r t e b r a l numbers i n f i s h t o environmental i n f l u e n c e s d u r i n g development. Can. J . F i s h . Aquat. S c i . 38: 334-347. L i s t e r , D.B., D.G. Hickey and I. W a l l a c e . 1981. Review o f the e f f e c t s o f enhancement s t r a t e g i e s on the homing, s t r a y i n g and s u r v i v a l o f P a c i f i c salmonids. Volume 1. D.B. L i s t e r and A s s o c i a t e s L t d . , West Vancouver, B.C. 51p. Lively, CM. spatially  1986. Canalization versus developmental v a r i a b l e environment Am. Nat. 128: 561-572.  L o f t u s , K.H. 1981. 1464-1465.  Where  are  we  now?  Can.  J.  conversion  Fish.  Aquat.  in  a  S c i . 38:  Lyamin, K.A. 1949. R e s u l t s o f t a g g i n g P a c i f i c salmon i n the G u l f o f Kamchatka In P a c i f i c Salmon: S e l e c t e d a r t i c l e s from S o v i e t p e r i o d i c a l s . T r a n s l . from Russian, IPST Cat. No. 341 (1961) 184-190. Lynch, M. 1986. Random d r i f t , uniform s e l e c t i o n , population d i f f e r e n t i a t i o n . E v o l u t i o n 40: 640-643. Mahalanobis, P.C. 1936. On Nat. I n s t . S c i . I n d i a 2: Main,  K.L. 1987. microhabitat 170-180.  the g e n e r a l i z e d 49-55.  distance  and  the  degree  in s t a t i s t i c s .  P r e d a t o r avoidance i n Seagrass Meadows: selection , and cryptic coloration.  of  Proc.  Prey Behaviour, Ecology 68(1):  Mason, J.C. 1974. B e h a v i o u r a l ecology o f chum salmon f r y (Oncorhynchus i n a s m a l l e s t a u r y . J . F i s h . Res. Board Can. 31(1): 83-92.  keta)  Mattson, C R . and R.G. Rowland. 1963. Chum salmon s t u d i e s at T r a i t o r s Cove F i e l d S t a t i o n — J u n e 1960 to March 1963. Bur. Commer. F i s h . , B i o l . Lab., Auke Bay, A l a s k a , Ms. Rep. 63-11, 32p. Mayr, E. 1963. Animal S p e c i e s and E v o l u t i o n . Mass. 771p.  Belknap P r e s s , Harvard  Maynard-Smith, J .  Am.  1966.  Sympatric s p e c i a t i o n .  Nat. 100:  Univ.,  637-650.  McNamara, J.M., and A . I . Houston. 1987. S t a r v a t i o n and P r e d a t i o n as l i m i t i n g population s i z e . E c o l o g y 68(5): 1515-1519.  factors  McNeil, W.J. 1966. E f f e c t o f the spawning bed environment on r e p r o d u c t i o n o f pink and chum salmon. U.S. F i s h . W i l d l . Serv., F i s h . B u l l . 65: 495-523. Mead, R.W. and W.L. Woodall. 1968. Comparison o f sockeye salmon f r y produced by h a t c h e r i e s , a r t i f i c i a l channels and n a t u r a l spawning a r e a s . Int. Pac. Salmon F i s h . Comm. Prog. Rep. 20 41p.  285  Meffe, G.K. 1986. Conservation genetics f i s h e s . F i s h e r i e s 11: 14-23. Meffe, G.K. 1987. Conserving f i s h Env. B i o l . F i s h e s 18: 3-9.  and the management  genomes:  philosophies  o f endangered  and p r a c t i s e s .  M e r r i t t , M.F. and J.A. Raymond 1983. E a r l y l i f e h i s t o r y o f chum salmon i n the Noatak R i v e r and Kotzebue Sound. Alaska Dept. F i s h and Game, D i v . o f F i s h . Rehab. Enhan. and Dev., Report No. 1: 56p. M e r r i t t , M.F. and K. Roberson. 1986. M i g r a t o r y t i m i n g o f upper Copper River sockeye salmon s t o c k s and i t s i m p l i c a t i o n s f o r t h e r e g u l a t i o n o f the commercial f i s h e r y . North American J o u r n a l o f F i s h e r i e s Management 6 ( 2 ) : 216-225. Mihara, T., S. I t o , T. Hachiya, and M. Ichikawa. 1951. S t u d i e s on the change of f i s h i n g c o n d i t i o n s o f salmon i n Hokkaido. (1) The f i s h i n g c o n d i t i o n s on salmon. S c i . Rep. Hokkaido F i s h Hatch. 6: 27-133. M i l l e r , R.J. and E.L. Brannon 1982. The o r i g i n and development o f l i f e h i s t o r y p a t t e r n s i n P a c i f i c salmonids. IN Proceedings o f the Salmon and Trout M i g r a t o r y Behaviour Symposium. E.L. Brannon and E.O. S a l o ( e d s ) . 1st I n t e r n a t i o n a l Symposium, School o f F i s h e r i e s , Univ. Washington, S e a t t l e , Washington, 98195. pp. 296-309. Mundy, P.R. 1982. Computation o f m i g r a t o r y t i m i n g s t a t i s t i c s f o r a d u l t chinook salmon i n t h e Yukon R i v e r , A l a s k a and t h e i r r e l e v a n c e to f i s h e r i e s management. North American J o u r n a l o f F i s h e r i e s Management 2(4): 359-370. Murray, C.B. 1980. Some e f f e c t s o f temperature on zygote and a l e v i n s u r v i v a l , r a t e o f development and s i z e at h a t c h i n g and emergence o f P a c i f i c salmon and rainbow t r o u t . M.Sc. T h e s i s , Univ. B r i t i s h Columbia, Vancouver, B.C. 156p. Murray, C.B., and T.D. Beacham. 1987. The development o f chinook (Oncorhynchus tshawytscha) and chum salmon (Oncorhynchus keta) embryos and a l e v i n s under v a r y i n g temperature regimes. Can. J . Z o o l . 65: 2672-2681. Naevdal, G., M. Holm, 0. I n g e b r i g h t s e n , and D. M o l l e r . age a t f i r s t spawning i n A t l a n t i c salmon (Salmo Board Can. 35: 145-147. Neave, F. 1949. Game f i s h p o p u l a t i o n s o f t h e Cowichan Res. Bd. Can. 84. 32 p.  1978. V a r i a t i o n i n s a l a r ) J . F i s h . Res.  River.  Bull.  Fish.  Neave, F. 1953. P r i n c i p l e s a f f e c t i n g t h e s i z e o f pink and chum salmon p o p u l a t i o n s i n B r i t i s h Columbia. J . F i s h . Res. Bd. Can. 9: 450-491. Neave, F. 1955. Notes on t h e seaward m i g r a t i o n o f pink and chum salmon f r y . J. F i s h . Res. Bd. Can. 12: 369-374.  286  Neave, F. 1966. Salmon o f the North P a c i f i c Ocean - Part I I I . A review o f the l i f e h i s t o r y o f North P a c i f i c salmon. 6. Chum salmon i n B r i t i s h Columbia. I n t . N. Pac. F i s h . Comm., B u l l . 18:81-86 Neave, F., T. Yonemori, and R. Bakkala. 1976. D i s t r i b u t i o n and o r i g i n o f chum salmon i n o f f s h o r e waters o f the North P a c i f i c Ocean. I n t . North Pac. F i s h . Comm. B u l l . 35: 79p. Nicola, S . J . 1962. Scavenging by A l l o p e r l a ( P l e c o p t e r a : C h l o r o p e r l i d a e ) nymphs on dead pink (Oncorhynchus gorbuscha) and chum (0. keta) salmon embryos. Can. J . Z o o l . 46: 787-796. Nei, M. 1971. I n t e r s p e c i f i c gene d i f f e r e n c e s and e v o l u t i o n a r y time estimated from e l e c t r o p h o r e t i c data on p r o t e i n i d e n t i t y . Am. Nat. 105: 385-398. Nei, M.  1972. G e n e t i c  d i s t a n c e between p o p u l a t i o n s .  N e i , M. 1978. E s t i m a t i o n o f average h e t e r o z y g o s i t y a s m a l l number o f i n d i v i d u a l s . G e n e t i c s 89: N i k o l ' s k i i , G.V. 1952. The type o f dynamics o f spawnig o f t h e chum Oncorhynchus keta Oncorhynchus gorbuscha (Walb.) i n t h e Amur S e l e c t e d a r t i c l e s from S o v i e t p e r i o d i c a l s . C a t . No. 341 (1961):9-12.  Am. Nat.  106:  283-292.  and g e n e t i c d i s t a n c e  from  s t o c k s and t h e c h a r a c t e r o f (Walb.) and pink salmon River. In P a c i f i c Salmon: T r a n s l . from Russian, IPST  Noerenberg, W.H. 1971. Earthquake damage t o Alaskan f i s h e r i e s . Pp. 170-193 IN The great A l a s k a earthquake o f 1964, B i o l o g y . N a t l . Res. C o u n c , N a t l . Acad. S c i . , Washington, D.C. Norman, J.R. 1975. A H i s t o r y o f F i s h e s . (3rd E d i t i o n ) London. 465p. Northcote, T.G. 1978. M i g r a t o r y s t r a t e g i e s and p r o d u c t i o n i n freshwater fishes. IN: Ecology o f freshwater f i s h p r o d u c t i o n , S.D. G e r k i n g , e d . B l a c k w e l l S c i . P u b l . Oxford: 326-329. Northvedt, R. 1986. The t i m i n g o f emergence o f A t l a n t i c salmon and rainbow t r o u t , incubated o f d i f f e r e n t s u b s t r a t e s . IN Proceedings o f counc. Meet, o f t h e i n t . counc. f o r the E x p l o r a t i o n o f t h e s e a . ICES, Copenhagen ( e d s ) : 33 pp. Nyman, L. 1972. A new approach t o t h e taxonomy o f the " S a l v e l i n u s a l p i n u s s p e c i e s complex" Rep. I n s t . Freshwater Res. Drottningholm 52: 103-131. Nyman, L. 1980. The p o p u l a t i o n g e n e t i c s o f A r t i e c h a r : A s t a t e o f the a r t . In Proceedings o f the f i r s t ISACF workshop on A r t i e charr. Inst. Freshwater Research, D r o t t n i n g h o l m , Sweden pp. 46-48. . Okazaki, T. 1978. Genetic d i f f e r e n c e s o f two chum salmon (Oncorhynchus keta) p o p u l a t i o n s r e t u r i n g t o t h e Tokachi R i v e r . B u l l . F a r Seas F i s h . Res. Lab. 16: 121-127.  287  Okazaki, T. 1981. G e o g r a p h i c a l d i s t r i b u t i o n o f a l l e l i c v a r i a t i o n s of enzymes i n chum salmon, Oncorhynchus keta, p o p u l a t i o n s i n North America. Bull. Japan. Soc. S c i . F i s h . 47: 507-514. Okazaki, T. 1983. populations.  G e n e t i c s t r u c t u r e o f chum salmom, Oncorhynchus keta, B u l l . Jap. Soc. S c i . F i s h . 49(2): 189-196.  river  Olsen, K.H. 1986. Chemo-attraction between j u v e n i l e s o f two sympatric s t o c k s of a r t i c c h a r r , S a l v e l i n u s a l p i n u s (L.) and t h e i r gene frequency of serum esterases. J . F i s h . B i o l . 28(2): 221-231. Parsons, P.A. 1977. Genes, behaviour and D r o s o p h i l a Adv. G e n e t i c s . 19: 1-32.  evolutionary processes:  The  genus  Parker, R.R. 1962. A concept o f the dynamics o f pink salmon p o p u l a t i o n s . In: N.J. Wilimovsky ( e d . ) , Symposium on pink salmon, pp 203-211. H.R. Macmillan L e c t u r e s i n F i s h e r i e s , Univ. B r i t . Columbia, Vancouver. Payne, R.H.' A.R. C h i l d , and A. F o r r e s t . 1971. A t l a n t i c salmon. Nature 231: 250-252. Pearson, K. 1926. 105-117.  On  the  coefficient  of  Geographical  racial  v a r i a t i o n i n the  likeness.  Biometrika  8:  Peterman, R.H. and M. Gatto. 1978. E s t i m a t i o n o f f u n c t i o n a l responses o f p r e d a t o r s on j u v e n i l e salmon. J . F i s h . Res. Board. Can. 28: 1503-1510. Pimentel, D., G.J.C. Smith and D. Scans. 1967. sympatric s p e c i a t i o n . Am. Nat. 101: 493-504.  A  population  model  P l y t y e z , B., J . Dulak, and P e c i o . 1984. G e n e t i c c o n t r o l o f l e n g t h of l a r v a l p e r i o d i n Rana t e m p o r a r i a . F o l i a B i o l . 32(3): 155-166. Prager, E.M. and A.C. Wilson. Mol. E v o l . 11: 129-142.  1978.  Methods o f p h y l o g e n e t i c  analysis.  of  the  J.  P r i t c h a r d , A.L. 1943. The age of chum salmon taken i n commercial c a t c h e s i n B r i t i s h Columbia. F i s h . Res. Bd. Can., P r o g r . Rep. Pac. Coast S t a . 54: 9-11. Quinn, T.P. 1984. Homing and s t r a y i n g i n P a c i f i c salmon. IN: J.D. McCleave, G.P. A r n o l d , J . J . Dodson and W.H. N e i l l . (Eds.) Mechanisms of m i g r a t i o n in fishes, pp. 357-362. Quinn, T.P. and K. F r e s h . 1984. Homing and s t r a y i n g i n chinook salmon (Oncorhynchus tshawytscha) from C o w l i t z R i v e r Hatchery, Washington. Can. J . F i s h . Aq. S c i . 4 1 ( 7 ) : 1078-1082. Quinn, T.P. 1985. Homing and the e v o l u t i o n o f sockeye salmon. Migration: Mechanisms and a d a p t i v e s i g n i f i c a n c e . Rankin, M.A., Checkley, J . C u l l e n , C. K i t t i n g , and P. Thomas ( e d s . ) : 353-366.  IN: D.  288  Quinn, T.P. and G.M. Tolson. 1986. Evidence o f c h e m i c a l l y p o p u l a t i o n r e c o g n i t i o n i n coho salmon (Oncorhynchus k i s u t c h ) Z o o l . 64: 84-87.  mediated Can. J .  Quinn, T.P. and R.F. Tallman. 1987. Seasonal environmental p r e d i c t a b i l i t y and homing i n r i v e r i n e f i s h e s . Env. B i o l . F i s h e s 18(2): 155-159. R e f s t i e , T. and T.A. S t e i n e . 1978. S e l e c t i o n experiments with salmon I I I . G e n e t i c and environmental sources o f v a r i a t i o n i n l e n g t h and weight o f A t l a n t i c salmon i n the freshwater phase. Aquaculture 14: 221-234. R i c k e r , W.E. 1959. V e r n a l and heimal F i s h . Res. Bd. Can. 16: 515-537.  races  among anadromous  R i c k e r , W.E. 1964. Ocean growth and m o r t a l i t y o f pink F i s h . Res. Bd. Can. 21: 905-931.  fishes.  J.  and chum salmon.  J.  R i c k e r , W.E. 1972. H e r e d i t a r y and environmental f a c t o r s a f f e c t i n g c e r t a i n salmonid p o p u l a t i o n s p.19-160. In R.C. Simon and P.A. L a r k i n ed. The Stock Concept i n P a c i f i c Salmon. H.R. MacMillan L e c t u r e s i n F i s h e r i e s , Univ. B r i t i s h Columbia, Vancouver, B.C.. R i c k e r , W.E. 1976. Review o f t h e r a t e o f growth and m o r t a l i t y o f P a c i f i c salmon i n s a l t w a t e r , and noncatch m o r t a l i t y caused by f i s h i n g . J. Fish. Res. Bd. Can. 33(7): 1483-1524. R i d d e l l , B.E. and W.C. Leggett. 1981. Evidence f o r an adaptive b a s i s f o r geographic v a r i a t i o n i n body morphology and time o f downstream m i g r a t i o n i n j u v e n i l e A t l a n t i c salmon (Salmo s a l a r ) . Can. J . F i s h . Aquat. S c i . 38: 308-320. R i d d e l l , B.E., W.C. Leggett and R.L. Saunders. 1981. Evidence o f a d a p t i v e p o l y g e n i c v a r i a t i o n between two p o p u l a t i o n s o f A t l a n t i c salmon (Salmo s a l a r ) n a t i v e t o t r i b u t a r i e s o f S.W. Miramichi R i v e r , N.B., Can. Can. J . F i s h . Aquat. S c i . 38: 321-333. Robertson, A. 1955. S e l e c t i o n i n animals: Symp. Quant. B i o l . 20: 225-229.  synthesis.  Cold  Spring  Harbor  Rodda, D., L. S c h a f f e r , K. Mullen and G. F r i a r s . 1977. Measuring the p r e c i s i o n o f g e n e t i c parameters by s i m u l a t i o n t e c h n i q u e . Theor. App. Genet. 51: 35-40. Rosly, Yu. 1972. The s c a l e s t r u c t u r e o f the Amur chum (Oncorhynchus k e t a (Walb.)) as an i n d i c a t o r o f growth and l i v i n g conditions i n the freshwater s t a g e . J . I c h t h y o l . 12(3): 483-497. Roughgarden, J . 1979. Theory o f p o p u l a t i o n genetics ecology: An I n t r o d u c t i o n . M a c M i l l a n , New York 634 p.  and  evolutionary  289  Rugh,  R. 1952. Experimental M i n n e a p o l i s , MN. 480p.  embryology.  Burgess  Rutberg, A.T. 1987. Adaptive hypotheses o f b i r t h synchrony interspecific test. Am. Nat. 130(5): 692-710.  Publishing  Co.,  i n ruminants:  an  Ryman, N., F.W. A l l e n d o r f and G. S t a h l . 1979. Reproductive i s o l a t i o n with l i t t l e g e n e t i c d i v e r g e n c e i n sympatric p o p u l a t i o n s o f brown t r o u t (Salmo trutta). G e n e t i c s 92: 247-262. Ryman, N. and G. S t a h l . 1981. G e n e t i c p e r s p e c t i v e s o f the i d e n t i f i c a t i o n and conservation o f Scandinavian stocks o f f i s h . Can. J . F i s h . Aq. S c i . 38(12): 1562-1575. Salo,  E.O. 1986. The l i f e h i s t o r y o f chum salmon (Oncorhynchus k e t a ) . FRI Univ. Washington, S e a t t l e , Washington. 238 p. MS.  Salo,  E.O. and R.E. Noble 1952. M i n t e r Creek B i o l o g i c a l S t a t i o n , P r o g r e s s Report (Sept-Dec. 1952). P a r t I: Chum salmon. Washington Dept. F i s h , Olympia, WA. 33p.  Sano, S. 1959. The ecology and p r o p a g a t i o n o f genus Oncorhynchus n o r t h e r n Japan. S c i . Rep. Hokkaido Salmon Hatch. 14:21-90 Sano, S. life Int.  found i n  1966. Salmon o f the North P a c i f i c Ocean. Part I I I . A review o f the h i s t o r y o f North P a c i f i c salmon, 3. chum salmon i n the F a r E a s t , N. Pac. F i s h . Comm., B u l l . 18: 41-57.  S a v i a a t o v a , K.A. 1983. The a p p l i c a t i o n o f the b i o l o g i c a l s p e c i e s concept t o an e v a l u a t i o n o f the s y s t e m a t i c p o s i t i o n o f c h a r s o f the genus S a l v e l i n u s (Salmonidae). J . I c h t h y o l . 23(6): 1-12. Schmidt, P.Yu. 1947. Sci. Press.  Fish  m i g r a t i o n s . Moscow,  Leningrad,  U.S.S.R.  Acad.  Schroder, S.L. 1973. E f f e c t s o f d e n s i t y on spawning s u c c e s s o f chum salmon (Oncorhynchus keta) i n an a r t i f i c i a l spawning c h a n n e l . M.Sc. T h e s i s , Univ. Wash., S e a t t l e , Wash. 78p. Schroder, S.L. 1974. Assessment o f p r o d u c t i o n o f chum salmon f r y form the Big Beef Creek spawning c h a n n e l . Univ. Washington, F i s h . Res. I n s t . , Anadromous F i s h P r o j e c t , Annu. Rep. FRI-UW-7413. 56 p. Schroder, S.L. 1977. Assessment o f p r o d u c t i o n o f chum salmon f r y from the Big Beef Creek spawning c h a n n e l . Completion Report. F i s h . Res. I n s t . , Univ. Washington, S e a t t l , WA. FRI-UW-7718: 77p. Schroder, S.L. 1981. The r o l e o f s e x u a l s e l e c t i o n i n d e t e r m i n i n g o v e r a l l mating p a t t e r n s and mate c h o i c e i n chum salmon. Ph.D. T h e s i s , C o l l e g e o f F i s h e r i e s , U n i v e r s i t y o f Washington.  290  S e m l i t s c h , R.D., D.E. S c o t t and J.H.K. Pechmann. 1988. Time and metamorphosis r e l a t e d to a d u l t f i t n e s s i n Ambystoma talpoideum. 69: 184-192.  s i z e at Ecology  Seymour, A. 1959. E f f e c t s o f temperature upon the f o r m a t i o n of v e r t e b r a e and f i n rays i n young chinook salmon. T r a n s . Am. F i s h . Soc. 88(1): 58-69. Sheridan, W.L. 1962. R e l a t i o n o f stream temperatures to t i m i n g o f pink salmon escapements i n Southeast A l a s k a . IN: Symposium on Pink Salmon, H.R. Macmillan L e c t u r e s i n F i s h e r i e s , Univ. B r i t i s h Columbia, Vancouver pp. 87-102 Silliman. 73:  1975. 495-  Selective  and  unselective fishing.  Fishery Bulletin  Vol.  Shine, R. 1988. The e v o l u t i o n o f l a r g e body s i z e i n Females: A critique Darwin's " F e c u n d i t y advantage" model. Am. Nat. 131: 124-131.  of  S i b e r t , J.R. 1979. D e t r i t u s and j u v e n i l e salmon p r o d u c t i o n i n the Naniamo Estuary: I I . Meiofauna a v a i l a b l e as food to j u v e n i l e chum salmon (Oncorhynchus k e t a ) . J . F i s h . Res. Board Can. 36: 497-503. Simenstad, C.A., W.J. Kinney, S.S. P a r k e r , E.O. S a l o , J.R. Cordell, and Heuchner. 1980. Prey community s t r u c t u r e and t r o p h i c ecology of o u t m i g r a t i n g j u v e n i l e chum and pink salmon i n Hood C a n a l , Washington: A s y n t h e s i s o f t h r e e y e a r s ' s t u d i e s , 1977-1979. F i n a l Rep., Fish. Res. INst., Univ. Washington, S e a t t l e , WA. FRI-UW-8026. 113 p. Simenstad, C.A., K.L. Fresh, and E.O. S a l o . and Washington c o a s t a l e s t u a r i e s i n the and u n a p p r e c i a t e d f u n c t i o n , p. 343-364. Kennedy ( e d . ) . Academic P r e s s .  1982. The r o l e o f Puget Sound l i f e h i s t o r y of P a c i f i c salmon: In E s t u a r i n e Comparisons, V.S.  Singh, R.S., R.C. Lewontin, and A.A. F e l t o n . 1976. Genetic w i t h i n e l e c t r o p h o r e t i c " a l l e l s " o f xanthine dehydrogenase pseudoobscura. G e n e t i c s 84: 609-629.  heterogeneity in Drosophila  S l a t k i n , M. 799-811.  Evolution  1987.  Quantitative  genetics  of  heterochrony.  41:  Smirnov, A . I . 1955. The e f f e c t o f mechanical a g i t a t i o n at d i f f e r e n t p e r i o d s o f development on the eggs o f autumn salmon (Oncorhynchus keta) i n f r a s p . autumnalis Berg, Salmonidae). F i s h . Res. Board Can. T r a n s l . S e r . No. 230, 1959. Smirnov, A.I. 1975. The b i o l o g y , r e p r o d u c t i o n and development o f the salmon. F i s h . Mar. Serv. T r a n s l . Ser. 3861. 335 p.  Pacific  Smith, S.B. 1969. Reproductive i s o l a t i o n i n summer and w i n t e r races of steelhead t r o u t . p. 21-38. In T.G. Northcote ed. Symposium on Salmon and Trout i n Streams. H.R. MacMillan Lectures i n F i s h e r i e s , Univ. B r i t i s h Columbia.  291  Smoker, W.W. 1982. Q u a n t i t a t i v e g e n e t i c s o f chum salmon, Oncorhynchus (Walbaam) Oregon State Univ. Ph.D. T h e s i s . 170 p. S o k a l , R.R. and F . J . R o h l f . New York, N.Y. 859 p. S p a l d i n g , D.J. and harbor B u l l . 146: S p i e t h , P.T. 961-965.  1981.  Biometry, 2nd Ed.  1974.  Gene  flow  and  genetic  P a t t e r n and p r o c e s s .  1977. The e v o l u t i o n o f l i f e 145-172. 1976.  differentiation.  Genetics  Co.  78:  Genetic differentiation among n a t u r a l p o p u l a t i o n s (5almo s a l a r ) i n n o r t h e r n Sweden. E c o l . B u l l 34:  S t a n l e y , S.M. 1979. Macroevolution: Co. San F r a n c i s c o . 332 p.  S t e b b i n s , G.L. 1-34.  Freeman and  1964. Comparative f e e d i n g h a b i t s o f the f u r s e a l , sea l i o n s e a l on the B r i t i s h Columbia c o a s t . F i s h . Res. Bd. Can., 52 p.  S t a h l , G. 1981. A t l a n t i c salmon  S t e a r n s , S.C. S y s t . 8:  W.H.  keta  Chromosome, DNA  and  history  traits.  plant evolution.  W.H.  Ann.  of  Freeman and  Rev.  Ecol.  Evol. B i o l .  9:  Svetovidova, A.A. 1961. L o c a l s t o c k s o f summer keta, Oncorhynchus keta (Walbaum), o f the Amur B a s i n . F i s h . Res. Board. Can. T r a n s l . S e r . No. 347. 11 p. Swain, D.P. 1987. A problem with the use o f m e r i s t i c c h a r a c t e r s to e s t i m a t e developmental s t a b i l i t y . Am. Nat. 129: 761-768. Swain, D. and C C . L i n d s e y . 1984. S e l e c t i v e p r e d a t i o n f o r v e r t e b r a l number of young s t i c k l e b a c k s ( G a s t e r o s t e u s a c u l e a t u s ) . Can. J . F i s h . Aq. S c i . 41: 1231-1233. Swofford, D.L. 1981. On the u t i l i t y o f the d i s t a n c e Wagner procedure. IN V.A. Funk and D.R. Brooks (eds) Advances i n c l a d i s t i c s : proceedings of the f i r s t meeting o f the W i l l i e Hennig S o c i e t y . New York, N.Y. 25-43 p. Taguchi, K. 1961. A t r i a l t o e s t i m a t e the i n s t a n t a n e o u s r a t e o f n a t u r a l m o r t a l i t y o f a d u l t salmon (Oncorhynchus sp.) and the c o n s i d e r a t i o n o f rationality of offshore f i s h i n g . I. For chum salmon (Oncorhynchus keta). B u l l . Jpn. Soc. S c i . F i s h . 27: 963-971. Taning, A.V. 1952. Experimental B i o l . Rev. 27: 169-193.  study  of m e r i s t i c characters  in  fishes.  Tauber, M.J. and C A . Tauber. 1976. E x p e r i m e n t a l c o n t r o l o f u n i v o l t i n i s m and i t s e v o l u t i o n . Ann. Rev. E c o l . S y s t . 12: 281-308.  292  Tauber, C A . and M.J. Tauber. 1981. Insect s e a s o n a l evolution. Ann. Rev. E c o l . S y s t . 12: 281-308.  cycles:  genetics  and  Tauber, C A . and M.J. Tauber, J.R. N e c h o l s . 1977. Two genes c o n t r o l i s o l a t i o n i n s i b l i n g species. Science 197: 592-593.  seasonal  T a y l o r , S.G. 1980. Marine s u r v i v a l o f p i n k salmon spawners. Trans Amer. F i s h . Soc. 109: 79-82.  and  f r y from e a r l y  T a y l o r , E.B. and J.D. M c P h a i l . 1985. V a r i a t i o n s i n body morphology B r i t i s h Columbia p o p u l a t i o n s o f coho salmon, Oncorhynchus k i s u t c h . J . F i s h . Aquat. S c i . 42: 2020-2028. Templeton, A.R. 1981. Mechanisms of s p e c i a t i o n approach. Ann. Rev. E c o l . S y s t . 12: 23-48.  -  a  population  late  among Can.  genetic  Thoday, J.M. and T.B. Boam. 1959. E f f e c t s of d i s t r u p t i v e s e l e c t i o n I I I : Polymorphism and d i v e r g e n c e without i s o l a t i o n . H e r e d i t y 13: 205-218. Thoday, J.M. and J.B. Gibson. Nature 193: 1164-1166.  1962.  Thoday, J.M. 109-143.  selection.  1972.  Disruptive  Isolation  Proc.  by  disruptive  Roy.  Soc.  selection.  Lond.  (B)  182:  T h o r s t e i n s o n , F.V., W.H. Noerenberg, and H.D. Smith. 1963. The l e n g t h , age, and sex r a t i o o f chum salmon i n the A l a s k a P e n i n s u l a , Kodiak I s l a n d , and P r i n c e W i l l i a m Sound areas of A l a s k a . U.S. F i s h . W i l d l . Serv., Spec. S c i . Rep. F i s h . 430. 84 p. Todd,  I.S. 1966. A technique f o r the enumeration o f chum salmon f r y i n the F r a s e r R i v e r , B r i t i s h Columbia. The Can. F i s h . C u l t . 38: 3-35.  Trasky, L.T. 1974. Yukon R i v e r anadromous f i s h i n v e s t i g a t i o n s . Anadromous F i s h C o n s e r v a t i o n A c t , Completion Report f o r p e r i o d J u l y 1, 1973 t o June 30, 1974. A l a s k a Dept. F i s h and Game, Comm. F i s h . D i v . , Juneau, AK. 111 PT y l e r , A.V. 1966. Some l e t h a l temperature r e l a t i o n s genus Chrosomus. Can. J . Z o o l . 44: 349-361.  of two  minnows o f the  Van  den Berghe, E.P. and M.R. Gross. 1984. Female c o m p e t i t i o n , l i f e - t i m e r e p r o d u c t i v e s u c c e s s , and i n t e n s i t y o f n a t u r a l s e l e c t i o n i n coho salmon (Oncorhynchus k i s u t c h ) . Submitted t o E v o l u t i o n .  Van  V l e c k , L.D. 1973. Selection G e n e t i c s L e c t u r e s 3: 133-148.  for direct  and maternal g e n e t i c  V e l s e n , F.P. 1980. Embryonic development i n eggs o f sockeye Oncorhynchus nerka. Can. Spec. Pub. F i s h . Aquat. S c i . no. 49.  effects.  salmon,  293  V l a d i m i r o v , V.I. 1975. Critical I k t i o l . 15(6): 955-975.  periods  i n the development  of  fish.  Vopr.  Vourinen, J . , M. Himberg, and P. Lankinen. 1981. Genetic d i f f e r e n t i a t i o n in Coregonus a l b u l a (L.) (Salmonidae) p o p u l a t i o n s i n F i n l a n d . H e r e d i t a s 94: 113-121. W a l t e r s , C.J., R. H i l b o r n , R.M. Peterman, and M.J. S t a l e y . 1978. Model f o r examining e a r l y ocean l i m i t a t i o n o f P a c i f i c salmon p r o d u c t i o n . J. Fish. Res. Board. Can. 35(10): 1303-1315. Wehrhahn, C F . and R. P o w e l l . . 1987. Electrophoretic variation, regional d i f f e r e n c e s , and gene flow i n the coho salmon (Oncorhynchus k i s u t c h ) o f southern B r i t i s h Columbia. Can. J . F i s h . Aquat. S c i . 44: 822-831. White, M.J.D. 1978. U.S.A. 455 p.  Modes of s p e c i a t i o n .  Freeman  and  Co.  San  Francisco,  Whitmus, C J . and S. Olson. 1979. The m i g r a t o r y behaviour of j u v e n i l e chum salmon r e l e a s e i n 1977 from the Hood Canal Hatchery at Hoodsport, Washington. Univ. Washington, F i s h . Res. I n s t , , FRI-UW-7916. 46 p. W i c k e t t , W.P. 1954. F i s h . Res. Board  The Can.  oxygen s u p p l y t o salmon eggs i n spawning beds. 11(6): 933-953.  J.  W i c k e t t , W.P. 1958. Review o f c e r t a i n environmental f a c t o r s a f f e c t i n g p r o d u c t i o n o f pink and chum salmon. J. Fish. Res. Bd. Can. 1103-1126.  the 15:  W i t h l e r , R.E. 1988. Genetic (Oncorhynchus tshawytscha) 15-25.  consequences o f f e r t i l i z i n g Chinook salmon eggs with pooled m i l t . Aquaculture, 68:  W i t h l e r , R.E., M.C. Healey, and B.E. R i d d e l l . 1982. o f g e n e t i c v a r i a t i o n i n the f a m i l y Salmonidae. Aquat. S c i . No. 1098. 161 p.  Annotated b i b l i o g r a p h y Can. Tech. Rep. Fish.  W i t h l e r , R.E., B.E. R i d d e l l , and H. K r e i b e r g . 1987. freshwater survival and growth of chinook tshawytscha). A q u a c u l t u r e , 64: 85-96.  Genetic v a r i a t i o n i n salmon (Oncorhynchus  Wright,  S.  1931.  E v o l u t i o n i n mendelian p o p u l a t i o n s .  G e n e t i c s 16:  97-159.  Wright, S. 1969. E v o l u t i o n and the g e n e t i c s of p o p u l a t i o n s . Volume 2: theory o f gene f r e q u e n c i e s U n i v e r s i t y o f Chicago P r e s s , C h i c a g o .  The  Wright, S. 1978. E v o l u t i o n and the g e n e t i c s o f p o p u l a t i o n s volume 4: V a r i a b i l i t y w i t h i n and among n a t u r a l p o p u l a t i o n s . Univ. Chicago Press 580 p. Wright, S. 1988. 115-123.  Surfaces  and  selective  value  revisited.  Am.  Nat.  131:  294  APPENDIX 1  Analysis of variance tables estimating the e f f e c t of population and temperature regime f o r mean time t o hatch and emergence d u r i n g the 1982-83 and 1983-84 i n c u b a t i o n experiments.  295  Table a a . 1982-83 Mean Time t o Hatch  ( B a r t l e t t ' s T e s t - C h i Square = 18.28)  ANALYSIS OF VARIANCE SOURCE  SUM OF SQUARES  POP REGIME INTERACTION ERROR  DF  MEAN SQUARE  F  VALUE  TAIL PROBABILITY  581.9249  3  193.9750  40.55  0.0000  13706.8584  3  4568.9526  955.14  0.0000  796.1072  9  88.4564  18.49  0.0000  76.5368  16  4.7835  ANALYSIS OF VARIANCE; VARIANCES ARE NOT ASSUMED TO BE EQUAL 15, 6  1198.75  0.0000  POP  3, 4  40.55  0.0019  REGIME  3, 4  955.14  0.0000  INTERACTION  9, 4  18.49  0.0065  WELCH BROWN-FORSYTHE*  ALL GROUPS COMBINED (EXCEPT CASES WITH UNUSED VALUES FOR VARIABLES POP AND REGIME) MEAN STD. DEV. S. E. M. MAXIMUM MINIMUM CASES EXCLUDED CASES INCLUDED •ROBUST S.D.  86.920 22.115 3.909 128.262 53.150 ( 0) 32 22.137  296  1983-84 Mean Time to Hatch (Bartlett's Test - Chi Square = 25.01)  Table bb.  ANALYSIS OF VARIANCE SUM OF SQUARES  SOURCE POP REGIME INTERACTION  DF  MEAN SQUARE  F VALUE  TAIL PROBABILITY  705.7712  3  235.2571  39.10  0.0000  12729.1387  3  4243.0459  705.19  0.0000  1031.5887  9  114.6210  19.05  0.0000  96.2698  ERROR  16  6.0169  ANALYSIS OF VARIANCE; VARIANCES ARE NOT ASSUMED TO BE EQUAL WELCH  15, 6  6010.63  0.0000  3, 3  39.10  0.0066  . 3, 3  705.19  0.0001  BROWN-FORSYTHE* POP REGIME INTERACTION  9, 3  ALL GROUPS COMBINED (EXCEPT CASES WITH UNUSED VALUES FOR VARIABLES POP AND REGIME) MEAN STD. DEV. S. E. M. MAXIMUM MINIMUM CASES EXCLUDED CASES INCLUDED *ROBUST S.D.  90.419 21.674 3.831 131.190 53.995 ( 0) 32 21.780  19.05  0.0169  297  Table c c . = 19.21).  1982-83 Mean Time t o Emergence  (Bartlett's  Test  - C h i Square  ANALYSIS OF VARIANCE SOURCE  SUM OF SQUARES  POP REGIME INTERACTION ERROR  DF  MEAN SQUARE  F VALUE  TAIL PROBABILITY  1401.7726  3  467.2575  153.29  0.0000  30626.8750  3  10208.9580  3349.24  0.0000  775.4931  9  86.1659  28.27  0.0000  48.7703  16  3.0481  ANALYSIS OF VARIANCE; VARIANCES ARE NOT ASSUMED TO BE EQUAL WELCH  15, 6  1.97E+5  0.0000  BROWN-FORSYTHE* POP  3, 7  153.29  0.0000  REGIME  3, 7  3349.24  0.0000  INTERACTION  9, 7  28.27  0.0001  ALL GROUPS COMBINED (EXCEPT CASES WITH UNUSED VALUES FOR VARIABLES POP AND REGIME) MEAN STD. DEV. S. E. M. MAXIMUM MINIMUM CASES EXCLUDED CASES INCLUDED *ROBUST S.D.  137.717 32.554 5.755 173.225 81.715 ( 0) 32 34.749  298  T a b l e dd. 22.5 9 ) .  1983-84  Mean Time t o Emergence ( B a r t l e t t ' s Test - C h i Square r  ANALYSIS  OF  VARIANCE TAIL  SOURCE  SUM OF SQUARES  DF  MEAN SQUARE  F  VALUE  PROBABILITY  POP  1847. .0841  3  615.6947  115.30  0.0000  REGIME  8 5 6 4 .. 9 6 8 7  3  2854.9897  534.65  0.0000  362. ,8152  9  40.3128  7.55  0.0003  85. ,4391  16  5.3399  INTERACTION ERROR  A N A L Y S I S OF V A R I A N C E ; WELCH  VARIANCES ARE NOT ASSUMED TO BE EQUAL 15,  6  9054.60  0.0000  POP  3,  6  115.30  0.0000  REGIME  3,  6i  534.65  0.0000  INTERACTION  9,  6  7.55  0.0115  BROWN-FORSYTHE*  A L L GROUPS COMBINED (EXCEPT CASES W I T H UNUSED VALUES FOR V A R I A B L E S POP AND REGIME ) MEAN STD.  143.100 DEV.  18.717  S . E . M. MAXIMUM MINIMUM CASES EXCLUDED CASES INCLUDED *ROBUST S . D .  3.309 173.490 109.826 ( 0) 32 19.702  299  APPENDIX  2  Comparisons and c o n t r a s t s among means o f time t o hatch and time o f embryos r e a r e d i n the the 1982-83 and 1983-84 experiment. Calculation of C r i t i c a l a(n-1), alpha  to emergence  Value f o r SS-STP Test C. V. = (a - 1) x MSW  x F. (a-1),  300  T a b l e e e . Comparisons u s i n g t h e Sum o f Squares S i m u l t a n e o u s T e s t Procedure (SS-STP) ( G a b r i e l 1964) o f p o p u l a t i o n s w i t h i n t e m p e r a t u r e regime f o r 1982-83 t i m e t o h a t c h . ( C r i t i c a l V a l u e = 293.03, P = 0.01 o r 93.40, P r 0.05 ) . Temperature Comparison  6  Regime  10  EARLY  LATE  AB - WB  542.89**  1.69  6.25  190.44*  AB - W  309.76**  5.29  0.04  556.96**  7.29  96.04*  WB - W  32.49  12.96  WB - C  106.09*  4.41  21.16  32.49  136.89*  0.33  1.76  466.25**  11.60  2.80  371.85**  8.00  9.01  5.33  20.28  142.83*  W - C AB - (WB + W) W - (AB +  WB)  WB - (W + AB) WBxW - (WB + W)  557.60** 47.20 280.33** 74.00  81  1.21 75.69  19.25  301  T a b l e f f . Comparisons u s i n g t h e Sum o f S q u a r e s S i m u l t a n e o u s T e s t P r o c e d u r e (SS-STP) ( G a b r i e l 1964) o f p o p u l a t i o n s w i t h i n t e m p e r a t u r e regime f o r 1982-83 t i m e t o emergence. ( C r i t i c a l V a l u e = 152.71, P = 0.01 o r 60.30, P = 0.05 ) 3 . Temperature Comparison  6  Regime  10  EARLY  LATE  AB - WB  655.36**  5.29  0.25  306.25**  AB - W  292.41**  32.49  372.49**  676.00**  11.56  392.04**  72.25  2.89  53.29  WB - W WB - C W - C AB - (WB + W) W - (AB + WB)  72.25 396.01**  2.25  129.96*  24.01  462.25**  249.64**  607.76**  21.  117.81*  630.75**  27.60  509.60**  396.75**  24.65  WB - (AB + W)  387.60**  0.40  C - (WB + W)  326.56**  13.65  137.36* 179.41**  27 177.87**  302  Table gg. Comparisons u s i n g t h e Sum o f Squares S i m u l t a n e o u s T e s t P r o c e d u r e (SS-STP) ( G a b r i e l 1964) o f p o p u l a t i o n s w i t h i n temperature regime f o r 1983 -84 t i m e t o h a t c h . ( C r i t i c a l Value - 301.42, P = 0.01 o r 119.01, P = 0.05 ) . Temperature Comparison  6 70.56  AB - WB  Regime  10  EARLY  LATE  100  70.56  30.25  AB - W  156.25*  18.49  196.00*  533.61**  WB - W  16.81  32.49  31.36  309.76**  WB - C  1.69  92.16  210.25*  W - C  29.16  234.09*  404.01**  34.81  145.60*  68.16  167.25*  272.65*  91.85  0.65  128.05*  552.16**  WB - (AB + W)  6.16  82.16  2.61  48.80  C - (WB + W)  14.96  206.67*  399.05**  11.21  AB - (WB + W) W - (AB +  WB)  136.89*  303  Table hh. Comparisons u s i n g t h e Sum o f Squares S i m u l t a n e o u s T e s t P r o c e d u r e (SS-STP) ( G a b r i e l 1964) o f p o p u l a t i o n s w i t h i n temperature regime f o r 1983-84 t i m e t o emergence. ( C r i t i c a l V a l u e = 267.37, P = 0.01 o r 105.57, P = 0.05 ) . Temperature Comparison AB - WB  6 47.61  10 1.69  Regime EARLY  LATE  289**  187.69*  256*  734.41**  AB - W  515.29**  116.64*  WB - W  249.64*  146.41*  1  WB - C  174.24*  163.84*  0.01  51.84  W -C  6.76  0.49  1.21  38.44  292.05**  30.08  363**  554.88**  494.08**  174.80*  75  546.75**  WB - (AB + W)  26.40  59.85  108*'  0.03  C - (WB +W)  37.45  60.75  AB - (WB +W) W - (AB + WB)  0.48  179.56*  0.33  304  APPENDIX 3  G - t e s t s o f independence of s u r v i v a l from f e r t i l i z a t i o n t o e p i b o l y o f embryos r e a r e d d u r i n g 1982-83 from the e f f e c t s o f temperature, p o p u l a t i o n , season o f spawning, l o c a t i o n o f spawning and egg s i z e .  305  T a b l e i i . Ho: S u r v i v a l o f 1982-83 progeny Independent o f Temperature o f I n c u b a t i o n . Population  d.f.  TOTAL  from  fertilization  t o epiboly G  12  1198.88 **  AB  3  437.81 **  WB  3  422.31 **  WBxW  3  166.41 **  W  -  3  132.55 **  306  Table j j . Ho: S u r v i v a l o f 1982-83 progeny Independent o f P o p u l a t i o n .  from  fertilization  to epiboly  Temperature  d.f.  G  TOTAL  12  1189.16 **  6  3  269.58 **  10  3  206.18 **  Early  3  319.31 **  Late  3  394.09 **  J  307  Table kk. Ho: S u r v i v a l o f 1982-83 progeny Independent o f Season o f Spawning. Temperature  d.f.  from  fertilization  to epiboly  G  TOTAL  4  85.41  6  1  6 0 . 4 8 **  10  1  1.15  Early  1  9.94  Late  1  **  **  1 3 . 8 4 **  308  T a b l e 11. Ho: S u r v i v a l o f 1982-83 progeny Independent o f L o c a t i o n o f Spawning. Temperature  d.f.  from  fertilization  t o epiboly  G  TOTAL  4  846.87 **  6  1  226.89 **  10  1  82.13 **  Early  1  122.48 **  Late  1  415.37 **  309  T a b l e mm. Ho: S u r v i v a l Independent o f Egg S i z e . Temperature  o f 1982-83 progeny  d.f.  from  fertilization  t o epiboly  G  TOTAL  4  188.64 **  6  1  33.11 **  10  1  36.83 **  Early  1  46.06 **  Late  1  72.64 **  310  APPENDIX 4  G - t e s t s o f independence o f s u r v i v a l from e p i b o l y t o eye pigment stage o f embryos reared d u r i n g 1982-83 from the e f f e c t s o f temperature, p o p u l a t i o n , season o f spawning, l o c a t i o n o f spawning and egg s i z e .  311  Table nn. Ho: S u r v i v a l o f 1982-83 progeny from e p i b o l y t o eye pigment Independent o f Temperature o f I n c u b a t i o n .  stage  Population  d.f.  G  TOTAL  12  2308.06 **  AB  3  281.69 **  WB  3  766.05 **  WBxW  3  729.90 **  W  3  530.52 **  312  Table oo. Ho: S u r v i v a l o f 1982-83 progeny from e p i b o l y t o eye pigment s t a g e Independent o f P o p u l a t i o n . Temperature TOTAL  d.f.  G  12  1981.41 **  6  3  324.64 **  10  3  170.51 **  Early  3  147.16 **  Late  3  1339.10 **  313  T a b l e pp. Ho: S u r v i v a l o f 1982-83 progeny from e p i b o l y t o eye pigment s t a g e Independent o f Season o f Spawning. Temperature  d.f.  G  TOTAL  4  818. 09  6  1  130. 66  10  1  161. 35  Early  1  4. 81  Late  1  521. 27  ** ** **  314  T a b l e qq. Ho: S u r v i v a l o f 1982-83 progeny from e p i b o l y t o eye pigment s t a g e Independent o f L o c a t i o n o f Spawning. Temperature  d.f.  G  TOTAL  4  465.48 **  6  1  270.72 * *  10  1  85.03 **  Early  1  99.52 **  Late  1  10.21 * *  315  Table r r . Ho: S u r v i v a l o f 1982-83 progeny from e p i b o l y Independent o f Egg S i z e . Temperature  d.f.  t o eye pigment s t a g e  G  TOTAL  4  668. 36 * *  6  1  13. 95 * *  10  1  27. 55 *-*•  Early  1  56. 03 •**  Late  1  570. 83 * *  316  APPENDIX 5  G - t e s t s o f independence o f s u r v i v a l from eye pigment stage t o hatch o f embryos r e a r e d d u r i n g 1982-83 from the e f f e c t s o f temperature, p o p u l a t i o n , season o f spawning, l o c a t i o n o f spawning and egg s i z e .  317  Table s s . Ho: S u r v i v a l o f 1982-83 progeny Independent o f Temperature o f I n c u b a t i o n . Population  d.f.  TOTAL  12  from eye pigment s t a g e t o h a t c h  G 1180.92 **  AB  3  814.03 **  WB  3  175.07 **  WBxW  3  27.87 **  W  3  163.95 **  318  T a b l e t t . Ho: S u r v i v a l o f 1982-83 progeny Independent o f P o p u l a t i o n . Temperature TOTAL  d.f.  from eye pigment s t a g e t o h a t c h  G  12  2571.87 **  6  3  832.57 **  10  3  545.53 **  Early  3  648.86 **  Late  3  544.91 **  319  Table uu. Ho: S u r v i v a l o f 1982-83 progeny Independent o f Season o f Spawning. Temperature  d.f.  from eye pigment s t a g e t o h a t c h G  TOTAL  4  806.71 *•*  6  1  416.57  10  1  3.75  Early  1  24.07  Late  1  362.32 * *  320  T a b l e v v . Ho: S u r v i v a l o f 1982-83 progeny Independent o f L o c a t i o n o f Spawning. Temperature  d.f.  from eye pigment s t a g e t o h a t c h  G  TOTAL  4  1233.67 * *  6  1  364.69 * *  10  1  174.63 * *  Early  1  156.67 **  Late  1  537.68 * *  321 T a b l e ww. Ho: S u r v i v a l o f 1982-83 progeny Independent o f Egg S i z e . Temperature  d.f.  from eye pigment  stage t o hatch G  TOTAL  4  414.53 **  6  1  9.76 **  10  1  105.53 **  Early  1  277.81 **  Late  1  21.43 **  322  APPENDIX  6  G - t e s t s o f independence o f s u r v i v a l from f e r t i l i z a t i o n to hatch o f embryos r e a r e d d u r i n g 1982-83 from the e f f e c t s o f temperature, p o p u l a t i o n , season o f spawning, l o c a t i o n o f spawning and egg s i z e .  323  Table x x . Ho: S u r v i v a l o f 1982-83 progeny Independent o f Temperature o f I n c u b a t i o n .  from  fertilization  to  hatch  Population  d.f.  TOTAL  12  3481. 06  AB  3  983. 55  WB  3  WBxW  3  201. 34  **  3  1217. 07  **  W  G  1079.  -X--X-  10  324  Table y y . Ho: S u r v i v a l Independent o f P o p u l a t i o n . Temperature TOTAL  o f 1982-83  progeny  d.f.  from  fertilization  t o hatch  G  12  3824.06 **  6  3  1182.93 * *  10  3  758.39 **  Early  3  1071.57 * *  Late  3  811.17 **  325  T a b l e z z . Ho: S u r v i v a l o f 1982-83 Independent o f Season o f Spawning. Temperature  progeny  d.f.  from  fertilization  t o hatch  G  TOTAL  4  628.48 **  6  1  522.47 * *  10  1  69.61 **  Early  1  0.0007  Late  1  36.41 * *  326  Table a a a . Ho: S u r v i v a l o f 1982-83 progeny Independent o f L o c a t i o n o f Spawning. Temperature  d .f.  from  fertilization  t o hatch  G  TOTAL  4  2070.84  6  1  860.17  10  1  315.17  Early  1  382.96  Late  1  566.54  ** ** **  327  Table bbb. Ho: S u r v i v a l Independent o f Egg S i z e . Temperature  o f 1982-83 progeny d.f.  from  fertilization  t o hatch  G  TOTAL  4  886.63 **  6  1  11.98 * *  10  1  86.39 **  Early  1  357.16 **  Late  1  431.10 * *  328  APPENDIX 7  G - t e s t s o f independence o f s u r v i v a l from hatch to emergence o f embryos reared during 1982-83 from the e f f e c t s o f temperature, population, season of spawning, l o c a t i o n o f spawning and egg s i z e .  329  Table e c c . Ho: S u r v i v a l o f 1982-83 Independent o f Temperature o f I n c u b a t i o n .  progeny  from  hatch  t o emergence  G  Population  d.f.  TOTAL  12  762.77 **  AB  3  21.11 **  WB  3  539.44 **  WBxW  3  83.05 **  3  119.17 **  W  330  T a b l e ddd. Ho: S u r v i v a l Independent o f P o p u l a t i o n . Temperature TOTAL  o f 1982-83  progeny  d.f.  from  hatch  t o emergence  G  12  952.28 **  6  3  676.60 **  10  3  105.79 **  Early  3  153.44 **  Late  3  16.45 **  331  Table e e e . Ho: S u r v i v a l o f 1982-83 Independent o f Season o f Spawning. Temperature  progeny  d.f.  from  hatch  t o emergence  G  TOTAL  4  162.45 **  6  1  38.93 **  10  1  97.32 **  Early  1  25.48 **  Late  1  0.72  332  Table f f f . Ho: S u r v i v a l o f 1982-83 Independent o f L o c a t i o n o f Spawning. Temperature  progeny  d.f.  from  hatch  t o emergence G  TOTAL  4  504.70 **  6  1  428.93 **  10  1  55.67 **  Early  1  13.42 **  Late  1  6.68  333  T a b l e ggg. Ho: S u r v i v a l Independent o f Egg S i z e . Temperature  o f 1982-83  progeny  d.f.  from  hatch  t o emergence  G  TOTAL  4  574.59 **  6  1  548.31 **  10  1  14.25 **  Early  1  2.91  Late  1  9.12 **  334  APPENDIX 8  G - t e s t s o f independence o f s u r v i v a l from f e r t i l i z a t i o n to e p i b o l y o f embryos r e a r e d d u r i n g 1983-84 from the e f f e c t s o f temperature, p o p u l a t i o n , season o f spawning, l o c a t i o n o f spawning and egg s i z e .  335  T a b l e hhh. Ho: S u r v i v a l o f 1983-84 progeny from f e r t t o e p i b o l y Independent o f Temperature o f I n c u b a t i o n . Population  d.f.  G  TOTAL  12  135.40 **  AB  3  14.66 **  WB  3  7.10 **  WBxW  3  27.52 **  W  3  86.12 **  336  Table i i i . Ho: S u r v i v a l o f 1983-84 progeny Independent o f P o p u l a t i o n . Temperature TOTAL  d.f.  from  fertilization  t o epiboly  G  12  4605.16 **  6  3  1042.47 **  10  3  628.29 **  Early  3  975.92 **  Late  3  1958.48 **  337  Table j j j . Temperature TOTAL 6  Ho: S u r v i v a l o f 1983-84 progeny from f e r t i l i z a t i o n t o e p i b o l y . d.f.  G  4  18.39  1 .  6.95  10  1  0.19  Early  1  4.34  Late  1  6.91  **  338  Table k k k . Ho: S u r v i v a l o f 1983-84 progeny Independent o f L o c a t i o n o f Spawning. Temperature  d.f.  from f e r t i l i z a t i o n  t o epiboly  G  TOTAL  4  128.60 **  6  1  44.62 **  10  1  53.23 **  Early  1  29.12 **  Late  1  1.63  339  T a b l e 111. Ho: S u r v i v a l Independent o f Egg S i z e . Temperature  o f 1983-84 progeny  d.f.  from  fertilization  to  epiboly  G  TOTAL  4  27.17  6  1  5.91  10  1  15.35  Early  1  4.08  Late  1  1.83  **  **  340  APPENDIX 9  G - t e s t s o f independence o f s u r v i v a l from e p i b o l y t o eye pigment stage o f embryos reared d u r i n g 1983-84 from the e f f e c t s o f temperature, p o p u l a t i o n , season o f spawning, l o c a t i o n o f spawning and egg s i z e .  341  Table mmm. Ho: S u r v i v a l o f 1983-84 progeny from e p i b o l y t o eye pigment s t a g e Independent o f Temperature o f I n c u b a t i o n . G  Population  d.f.  TOTAL  12  468.17 **  AB  3  28.12 **  WB  3  28.88 **  WBxW  3  354.04 **  W  3  57.13 **  342  T a b l e nnn. Ho: S u r v i v a l o f 1983-84 progeny from e p i b o l y t o eye pigment s t a g e Independent o f P o p u l a t i o n . Temperature TOTAL  d.f.  G  12  3272.99 **  6  3  578.70 **  10  3  396.86 **  Early  3  549.95 **  Late  3  1747.48 **  343  T a b l e ooo. stage. Temperature  Ho: S u r v i v a l  o f 1983-84  progeny  d.f.  from  epiboly  t o eye pigment  G  TOTAL  4  70.76 **  6  1  1.06  10  1  1.61  Early  1  29.20 **  Late  1  38.89 **  344  T a b l e ppp. Ho: S u r v i v a l o f 1983-84 progeny from e p i b o l y t o eye pigment s t a g e Independent o f L o c a t i o n o f Spawning. Temperature  d.f.  TOTAL  4  6  1  10  1  Early  1  Late  1  G 33.57 ** 4.39 12.62 ** 4.34 12.22 **  345  T a b l e qqq. Ho: S u r v i v a l o f 1983-84 progeny from e p i b o l y Independent o f Egg S i z e . Temperature  t o eye pigment s t a g e  d.f.  G  TOTAL  4  19.53  6  1  0.98  10  1  2.00  Early  1  4.15  Late  1  12.40  **  **  346  APPENDIX 10  G - t e s t s o f independence o f s u r v i v a l from eye pigment stage to hatch o f embryos r e a r e d d u r i n g 1983-84 from the e f f e c t s o f temperature, p o p u l a t i o n , season o f spawning, l o c a t i o n o f spawning and egg s i z e .  347  Table r r r . Ho: S u r v i v a l o f 1983-84 progeny from eye pigment s t a g e t o h a t c h Independent o f Temperature o f I n c u b a t i o n . Population  d.f.  G  TOTAL  12  446.36 **  AB  3  68.36 **  WB  3  46.53 **  WBxW  3  253.98 **  W  3  77.59 **  348  T a b l e s s s . Ho: S u r v i v a l o f 1983-84 progeny from eye pigment Independent o f P o p u l a t i o n . Temperature  d.f.  stage t o hatch  G  12  4108.34 **  6  3  1207.50 **  10  3  1595.39 **  Early  3  315.40 **  Late  3  990.05 **  TOTAL  349  Table t t t . Temperature  Ho: S u r v i v a l o f 1983-84 progeny from eye pigment s t a g e t o h a t c h . d.f.  G  TOTAL  4  42.94 **  6  1  29.23 **  10  1  Early  1  Late  1  0.45 13.26 ** 0.00  350  T a b l e uuu. Ho: S u r v i v a l o f 1983-84 progeny from eye pigment s t a g e t o h a t c h Independent o f L o c a t i o n o f Spawning. Temperature  d.f.  G  TOTAL  4  25.48 **  6  1  0.98  10  1  8.22  Early  1  Late  1  16.28 ** 0.00  351  T a b l e v v v . Ho: S u r v i v a l o f 1983-84 progeny from eye pigment s t a g e t o h a t c h Independent o f Egg S i z e . Temperature  d.f.  G  TOTAL  4  46.06 **  6  1  28.80 **  10  1  16.82 **  Early  1  0.44  Late  1  0.00  352  APPENDIX 11  G - t e s t s o f independence o f s u r v i v a l from f e r t i l i z a t i o n to hatch o f embryos r e a r e d d u r i n g 1983-84 from the e f f e c t s o f temperature, p o p u l a t i o n , season o f spawning, l o c a t i o n o f spawning and egg s i z e .  353  T a b l e www. Ho: S u r v i v a l o f 1983-84 progeny Independent o f Temperature o f I n c u b a t i o n .  from  fertilization  t o hatch  Population  d.f.  TOTAL  12  538.54 **  AB  3  27.46 **  WB  3  19.50 * *  WBxW  3  476.50 **  3  15.08 * *  W  G  354  T a b l e x x x . Ho: S u r v i v a l Independent o f P o p u l a t i o n . Temperature  o f 1983-84 progeny  from  fertilization  t o hatch  d.f.  G  12  11666.70 **  6  3  2963.82 **  10  3  2379.34 **  Early  3  1730.17 **  Late  3  4593.37 **  TOTAL  355 Table yyy. Temperature  Ho: S u r v i v a l o f 1983-84 progeny from f e r t i l i z a t i o n t o h a t c h . d.f.  G 43.42 **  TOTAL  4  6  1  1.44  10  1  4.71  Early  1  13.31 **  Late  1  23.96 **  356 Table z z z . Ho: S u r v i v a l o f 1983-84 progeny Independent o f L o c a t i o n o f Spawning. Temperature  d.f.  from  fertilization  t o hatch  G  TOTAL  4  26.74 **  6  1  9.51 **  10  1  8.04 **  Early  1  2.85  Late  1  6.34  357  Table aaaa. H o : Survival of 1 9 8 3 - 8 4 progeny from fertilization Independent of Egg Size. Temperature  d.f.  to hatch  G  TOTAL  4  26.63 **  6  1  16.85  10  1  0.22  Early  1  2.80  Late  1  6.76  **  358  APPENDIX 12  G - t e s t s o f i n d e p e n d e n c e o f s u r v i v a l from h a t c h t o emergence o f embryos r e a r e d during 1983-84 from the effects of temperature, population, season of s p a w n i n g , l o c a t i o n o f s p a w n i n g and e g g s i z e .  359  Table bbbb. Ho: S u r v i v a l o f 1983-84 Independent o f Temperature o f I n c u b a t i o n .  progeny  from  hatch  t o emergence  Population  d.f.  G  TOTAL  12  326.99 **  AB  3  114.78 **  WB  3  59.78 **  WBxW  3  96.16 **  W  3  55.27 **  360  Table c c c c . Ho: S u r v i v a l Independent o f P o p u l a t i o n . Temperature TOTAL  o f 1983-84  progeny  d.f.  from  hatch  t o emergence  G  12  5845.38 **  6  3  1172.55 **  10  3  1479.98 **  Early  3  2713.96 **  Late  3  478.89 **  361  Table dddd. Temperature  Ho: S u r v i v a l o f 1983-84 progeny from h a t c h t o emergence. d.f.  G  TOTAL  4  205. 79  6  1  128. 40  10  1  27. 43  **  Early  1  42. 24  **  Late  1  7. 72  **  362  T a b l e eeee. Ho: S u r v i v a l o f 1983-84 Independent o f L o c a t i o n o f Spawning. Temperature  progeny  d.f.  from  hatch  t o emergence  G  TOTAL  4  123.86 **  6  1  44.36 **  10  1  27.70 **  Early  1  51.80  Late  1  0.00  363  Table f f f f . Ho: S u r v i v a l Independent o f Egg S i z e . Temperature  o f 1983-84  progeny  d.f.  from  hatch  t o emergence  G  TOTAL  4  135.07 **  6  1  45.29 **  10  1  82.13 **  Early  1  0.72  Late  1  6.93 **  364  Appendix 13  Comparisons and c o n t r a s t s among means o f v