Open Collections

UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

A relation between aggressive behavior and population dynamics in blue grouse Mossop, David Harold 1971

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

Notice for Google Chrome users:
If you are having trouble viewing or searching the PDF with Google Chrome, please download it here instead.

Item Metadata

Download

Media
831-UBC_1971_A6_7 M68.pdf [ 7.66MB ]
Metadata
JSON: 831-1.0101885.json
JSON-LD: 831-1.0101885-ld.json
RDF/XML (Pretty): 831-1.0101885-rdf.xml
RDF/JSON: 831-1.0101885-rdf.json
Turtle: 831-1.0101885-turtle.txt
N-Triples: 831-1.0101885-rdf-ntriples.txt
Original Record: 831-1.0101885-source.json
Full Text
831-1.0101885-fulltext.txt
Citation
831-1.0101885.ris

Full Text

A RELATION BETWEEN AGGRESSIVE BEHAVIOR AND POPULATION DYNAMICS IN BLUE GROUSE by David H a r o l d Mossop B.Sc. H„, U n i v e r s i t y of Manitoba, 1966 A t h e s i s submitted i n p a r t i a l f u l f i l m e n t of the requirements f o r the degree of MASTER OP SCIENCE i n the Department of ZOOLOGY V/e accept t h i s t h e s i s as conforming to the r e o u i r e d standard THE UNIVERSITY OP BRITISH COLUMBIA September, 1971 In presenting t h i s thesis in p a r t i a l f u l f i l m e n t of the requirements for an advanced degree at the University of B r i t i s h Columbia, I agree that the Library shall make i t f r e e l y available for reference and study. I further agree that permission for extensive copying of t h i s thesis for scholarly purposes may be granted by the Head of my Department or by his representatives. It i s understood that copying or publication of this thesis f o r f i n a n c i a l gain shall not be allowed without my written permission. Depa rtment The University of B r i t i s h Columbia Vancouver 8, Canada ABSTRACT This study was a natural experiment to t e s t an hypothesis that blue grouse populations are regulated by aggressive behavior. Three natural populations were studied during two'successive breeding seasons. The environments of the three were e s s e n t i a l l y the same. The density of one remained stable at 5 t e r r i t o r i a l - males per 100 acres. The density of the second was d e c l i n i n g 10$ annually and was approximately 6 t e r r i t o r i a l males per 100 acres. The dens-i t y of the t h i r d was 35 t e r r i t o r i a l males per 100 acres and had r i s e n to t h i s density i n the previous three years. I t ceased to r i s e during the study. The annual m o r t a l i t y of adults was s i m i l a r i n a l l three. Annual recruitment i n any one year, was also s i m i l a r , however the population which was decreasing showed a lower recruitment over the term of the study. In the population which was i n c r e a s i n g i n dens-i t y , more chicks were produced per adult, than i n the pop-u l a t i o n which was decreasing. Production i n the stable pop-u l a t i o n was intermediate. Males i n the i n c r e a s i n g population, sang longer i n t o the season than those i n the other populations. Males i n the i n c r e a s i n g population hooted l e s s frequently i n response to humans and reacted l e s s aggressively to a r t i f i c i a l song than those at the other areas. A l l grouse i n the i n c r e a s i n g p o p u l a t i o n were l e s s f r e q u e n t l y observed on the ground and were h a r d e r to c a p t u r e t h a n those i n the o t h e r p o p u l a t i o n s . ' F l u s h d i s t a n c e s ' were l o n g e r , and the time t o f l u s h , was s h o r t e r than i n the o t h e r p o p u l a t i o n s . T h r e a t e n i n g c a l l s , "head d i p s " and "neck s t r e t c h e s " , a l l b e h a v i o r which i n - , d i c a t e s a g g r e s s i o n were observed more f r e q u e n t l y i n t h e de-c r e a s i n g and s t a b l e p o p u l a t i o n s . " F l u t t e r f l i g h t s " and " f e a t h e r s p r e a d d i s p l a y s " , g e s t u r e s which p r o b a b l y a l s o s e r v e as t h r e a t s , were r e c o r d e d more o f t e n i n the d e c l i n i n g and s t a b l e p o p u l a t i o n s . "Grouch and r u n " , a n o n - a g g r e s s i v e p a t t e r n , was observed more f r e q u e n t l y i n the i n c r e a s i n g pop-u l a t i o n . I n the d e c l i n i n g p o p u l a t i o n , hens showed more v i g o r o u s brood defense than those i n the i n c r e a s i n g . C h i c k s were f u r t h e r from the hen i n the i n c r e a s i n g p o p u l a t i o n , f l e w more r e a d i l y , and f l e w f u r t h e r when f l u s h e d . A r t i f i c i a l hen c a l l s caused t e r r i t o r i a l cocks i n a l l p o p u l a t i o n s t o a l t e r t h e i r songs s i m i l a r i l y . Males a t the d e c l i n i n g and s t a b l e p o p u l a t i o n s advanced more q u i c k l y toward the sound. Males i n a l l p o p u l a t i o n s c o u r t e d a dummy female s i m i l a r i l y . When r e a c t i n g t o a m i r r o r , males showed fewer a g g r e s s i v e a c t s p e r minute i n the i n c r e a s i n g p o p u l a t i o n . B e h a v i o r , i n c l u d i n g many types of a g o n i s t i c b e h a v i o r can v a r y between p o p u l a t i o n s . H o s t i l e i n t e r a c t i o n s have the p o t e n t i a l o f b e i n g l e s s severe i n the i n c r e a s i n g p o p u l -a t i o n . T h i s may have caused i t s i n c r e a s e . However, no cause and e f f e c t r e l a t i o n s h i p was demonstrated. i i i TABLE OF CONTENTS Page ABSTRACT i TABLE OF CONTENTS ' i i i LIST OF TABLES v LIST OF FIGURES v i i ACKNOWLEDGMENTS v i i i INTRODUCTION 1 The study areas 5 MATERIALS AND METHODS 10 a) Measuring the parameters and dynamics of the p o p u l a t i o n s 10 b) measuring behavior 12 RESULTS 15 P o p u l a t i o n d e n s i t i e s and trends 15 Annual m o r t a l i t y and age s t r u c t u r e of breeders 15 P r o d u c t i o n 20 a. Broodless hens 20 b. Chicks r a i s e d by s u c c e s s f u l hens 23 Summary of p o p u l a t i o n r e s u l t s 26 Behavior 27 a. Spontaneous behavior 27 b. Behavior of grouse i n response t o . o b s e r v e r 32 " I n t r a s p e c i f i c " behavior toward observer 35 P r e d a t o r avoidance behavior 4-1 c. Behavior i n the t e s t arena 48 T a b l e of c o n t e n t s ( c o n t ' d ) i v Page Summary of b e h a v i o r r e s u l t s DISCUSSION P o p u l a t i o n t r e n d s and dynamics The case f o r d i f f e r e n c e s i n a g g r e s s i o n between p o p u l a t i o n s A g g r e s s i o n and p o p u l a t i o n r e g u l a t i o n SUMMARY LITERATURE CITED APPENDICES Appendix 1 Appendix 2 Appendix 3 Appendix 4-Appendix 5 Appendix 6 Appendix 7 Appendix 8 Appendix 9 Appendix 1 0 Appendix 1 1 Appendix 1 2 Appendix 1 3 The v e g e t a t i v e c o v e r o f the study a r e a s i n 1 9 6 7 The p o p u l a t i o n d a t a c a r d " L i s t e n i n g t r a n s e c t s " f o r measuring b l u e grouse d e n s i t y A method of a g i n g b l u e grouse c h i c k s a t a d i s t a n c e A comparison of " b i r d s - p e r -hour" census and t o t a l s e a r c h census N e s t i n g phenology B e h a v i o r p a t t e r n s and c a l l s o f b l u e grouse w i t h a g o n i s t i c i n t e r p r e t a t i o n New d e s c r i p t i o n s of b e h a v i o r p a t t e r n s The d a t a c a r d f o r b e h a v i o r used toward o b s e r v e r Methods o f s t a l k i n g grouse and o b s e r v i n g b e h a v i o r H a n d l i n g b l u e grouse T e s t arena method I n t e r p r e t a t i o n o f the t e s t .arena b e h a v i o r ; number of t e s t s g i v e n 5 3 5 6 5 8 6 2 6 8 7 3 7 6 8 2 Appendix 14- - Repeat t e s t s o f same male V LIST OF TABLES Table Page I Summary of physical geography, climate and vegetation of the study areas. 9 I I Per cent yearling females among hens-.. 17 I I I Annual mortality of breeding males 18 IV The number of broodless hens by area V Fate of nests, 1967-68 2 3 VI Average size of broods i n f a l l , ( 5 0 - 70 day age class) 24-VII Number of songs sung per minute at C C , C.B., and M.Q.L 30 VIII Number of syllables i n blue grouse songs... 31 IX Successful capture attempts with noosing pole, °/o of t o t a l attempts, 1967-68 3 3 X Response of t e r r i t o r i a l males to observer and a r t i f i c i a l hooting, 1967-68 3 6 XI Number of birds giving " f l u t t e r f l i g h t " when flushed, 1967-68, in. per cent 3 7 XII Number of adult males which displayed toward observer, 1967-68, i n per cent 4.0 XIII Neck stretching and head dipping ob-served i n 100 encounters, 1967-68 4-1 XIV "Reluctance" to flush, Distance grouse moved on ground before flushing and the time from f i r s t disturbance to flushing, 1967-68 4 3 XV Brood defense behavior. The number of brood hens i n per cent, which showed "leading" and/or "rushing", 1967-68 4-4-XVI Vigor displayed by liens in brood defense behavior toward observer 4-5 XVII Number of chicks i n per cent which flew less than 50 meters when flushed 4-8 v i L i s t o f T a b l e s (Cont'd) Page XVIII A l t e r a t i o n s i n song and r a t e of advance of males d u r i n g response t o t e s t arena 4-9 XIX Number of a c t s o f c o u r t i n g observed per minute i n t e s t arena 50 XX Time i n minutes, t o f i r s t a g g r e s s i v e b e h a v i o r , i n t e s t arena 52 v i i LIST OP FIGURES Figure Page 1. Vancouver Island, showing locations of 2 . The Copper Canyon study area.. 8 3 . The densities of blue grouse, 1962-68. (Points prior to 1967 at M.Q.L. and C.B., from Zwickel, 1965; E l l i o t t , 1965; Lance, (unpublished) and Bendell (un-pUlt) 1 X Sill© Cl ) O 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 O 0 0 0 0 I S 4-. Mean brood sizes at 10 day intervals of 9.^ 0 " ^ S ) 0 0 0 0 0 0 0 O 0 O 0 0 0 O 0 0 0 0 O 0 0 0 0 0 0 0 0 0 * ^5 5 . Number of males participating i n hooting (#), 1967-68 29 6. Number of grouse seen before flushing as a % of t o t a l encountered 34-7 . Grouse showing "crouch and run" behavior i n per cent <,„.. 39 8. Flushing distances at M.Q.L., G.B., and C.C B 4-2 9 . Distance undisturbed chicks were observed from the hen 4-6 1 0 . Behavior of chicks when disturbed by 0"bS6-L?V6I* 0 _ > « O 0 0 0 0 « 0 0 e 0 e O 0 0 C 0 0 0 O 0 0 O 0 0 0 # 0 0 0 0 0 1 1 . Response of males to test arena by average number of aggressive acts per minute 51 12. Summary of behavior results. A comparison of behavior by population 55 v i i i ACMOWXEDGMENTS I am grateful to Dr. J. P. Bendell who supervised the study, provided financial support, and offered many suggestions during the preparation of the manuscript. My sincere appreciation i s also expressed to Dr. N. R. L i l e y , Dean I. McT. Cowan, Dr. J. M. Taylor, Dr. J. R. Adams and Dr„ J. Krebs for th e i r constructive c r i t i c i s m of the thesis. I acknowledge my f i e l d assistants, J. 0. Anvik, K. R. Bunnell, K. R. Summers and T. B„ Barnes who made the f i e l d work possible. I also acknowledge the assistance of my fellow students J. Theberge, A. T. Bergerud and K. R. Reid who engaged i n many helpful discussions. I am also pleased with the cooperation I received from the Comox Logging and Railway Division of Crown Zel l e r -bach of Canada and from the Copper Canyon Division of the MacMillan & Bloedel Company, on whose lands two of the study areas were situated. Special appreciation i s expressed to Jim Burdess of the Copper Canyon Division who ensured that I had no access d i f f i c u l t y and i n other ways made my study i n that area possible. The fine cooperation of the B.C. Fish and Wildlife Branch i s also acknowledged. Don Blood i s especially thanked for cooperating i n the operation of hunter check stations and for allowing me free access to his data. r-1-INTRODUCTION This study deals with one facet of a long-terra i n -vestigation into the population ecology of blue grouse (Dendragapus obscurus fuliginosus). The general objective of much of this larger investigation has been to explain how these birds maintain th e i r breeding densities i n nature (Bendell, 1 9 5 5 a ; Bendell & E l l i o t t , 1966, 1 9 6 7 ; Zwickel, 1 9 6 5 ) . These studies concluded that certain blue grouse populations on Vancouver Island were regulated. In spite of varying n a t a l i t y and mortality, the densities of the popul-ations i n spring remained r e l a t i v e l y constant. This phen-omenon of stable numbers was observed i n several populations, although between areas, large differences i n density were observed (Bendell & E l l i o t t , 1 9 6 7 ; Zwickel, 1 9 6 5 ) . From the study of these stable populations several general conclusions about the i r population dynamics seem v/e11 established. Mor* t a l i t y of breeders appears constant at approximately 30$ annually. Production of chicks each year i s apparently always more than sufficient to cover this loss. This i s reflected i n the return of only a small and constant number the follow-ing spring i n spite of a variable number alive up u n t i l winter (Bendell, 1 9 5 5 . and unpublished results; Zwickel, 1 9 6 5 ) . The main feature i n understanding the regulation of blue grouse populations i s to explain this apparent adjustment of -2-the number of young which disappear over winter. Various factors of the environment which can affect grouse survival have been examined i n attempts to explain this apparent adjustment of recruits. These factors have i n -cluded disease, weather, and vegetative cover (Bendell, 1 9 5 5 a ; E l l i o t t , 1965; Zwickel, 1965). However, no results to date have shown that any or a l l of these or any other en-vironmental variable i s necessary to explain the adjustment of numbers,, The present study was an attempt to examine the breeding stock i t s e l f to discover whether factors acting v/ith-i n the population might offer an explanation. Social behavior was chosen as the i n t r i n s i c factor to be examined. Recently, several studies have shown that social behavior can have consequences on the number of i n -dividuals i n natural animal populations. Notable among these are Southwick (1955); Krebs (1966); Sadlier (1965); Chitty & Phipps (1966); Healey (1967) and Watts (1969) a l l working with small rodents. Hornocher (1969) implemented social be-havior to explain cougar (Pelis concolor) numbers. Carrick (1963, 1964) explained magpie and g u l l numbers through social interaction and Tompa (1964) and Smith (1967) explained passerine bird populations s i m i l a r i l y . Behavior has also been examined i n various tetraonid populations i n attempts to understand th e i r population dy-namics. Foremost i n this work are Jenkins and Watson (1963, 1967) and Watson (1964, 1967 a,b) who showed that population density i n red grouse (Lagopus lagopus scoticus) was deter--3-mined by a competition for t e r r i t o r y i n f a l l . Territory size varied with the aggressiveness of the individuals. Bergerud ( 1 9 7 0 ) and Mercer ( 1 9 6 9 ) showed that i n willow ptarmigan, (Lagopus lagopus a l l e n i ) agression was highest i n a declining population and suggested that this was a result of selection for a more aggressive genotype which i n turn caused the ob-served decline. Blue grouse have also been examined. Bendell & E l l i o t t ( 1 9 6 7 ) studied t e r r i t o r i a l spacing i n the spring as a possible mechanism of population control. They removed breeding males and observed replacement, and concluded that considerable interaction occurred on the breeding grounds which eliminated some yearling males from breeding. However they f e l t the largest, and therefore c r i t i c a l , elimination of recruits had already occurred some time before t h e i r study commenced i n the spring. Lance ( 1 9 6 7 ) used telemetry to discover whether dispersion on the breeding range couldl adjust the numbers of recruiting birds. He found no evidence of t h i s . The con-clusion of both studies was that i f social interaction does regulate numbers of blue grouse, i t must act outside the breeding season. Wynne Edwards ( 1 9 6 2 ) hypothesized that natural popu-lations are regulated through the effect of social behavior. I f behavior has t h i s role of causing populations to regulate, and i f population changes are seen as part of the natural process of regulation, i t follows that animal behavior, measured at the population l e v e l , must be variable. Basically -4-thi s study questions that prediction. More recently, Chitty ( 1 9 6 5 , 1 9 6 7 ) formulated an hypothesis which contends that the behavioral effect upon recruitment i s mediated by virtue of the innate aggressiveness of the animals making up the population. That i s , populations which d i f f e r i n the trend of t h e i r densities, are made up of individuals which also d i f f e r i n the amount of aggressive behavior they exhibit, (Chitty, 1 9 6 7 ) . Refraining th i s as a n u l l hypothesis for the purpose of study, the following negative statements w i l l form the basis for discussion: a) "There i s no difference i n the behavior of blue grouse from different areas, regardless of the population dynamics i n the areas." or: b) "Increasing populations w i l l not be composed of less aggressive birds than stable, or especially, declining ones." The f i r s t part of the statement serves as a test of the general hypothesis that behavior can cause population regulation. The second i s a more specific test of the idea that regulation-i s caused by aggressive behavior i n the way described by Chitty ( 1 9 6 7 ) . Obviously the f i r s t part of the statement may be true while the second i s f a l s e , but not ,.,- versa. To test t h i s , three breeding populations were studied simultaneously. The population dynamics and aggressive be-havior of each were compared. The basis of this study was set by the uncommon occurrence i n nature, of an unstable - 5 -( d e c l i n i n g ) blue grouse p o p u l a t i o n combined w i t h the r e c e n t i n c r e a s e of another. These two were compared, a l o n g w i t h another s t a b l e p o p u l a t i o n . The study areas The l o c a t i o n s of the study areas on Vancouver I s l a n d , B.C., are shown i n P i g . 1. Middle Quinsam Lake a r e a (M.Q.L.) l i e s approximately 21 m i l e s northwest of the Comox Burn area (C.B.), and the Copper Canyon area ( C C ) , i s approximately 85 m i l e s southeast o f C.B. The f i r s t two areas have been s t u d i e d i n the past ( B e n d e l l & E l l i o t t , 1 9 6 ? ; Z w i c k e l , 1 9 6 5 ; Lance, 1 9 6 7 ; King, 1 9 6 8 ) . xhe C C . area i s new, although the B.C. P i s h & W i l d l i f e Branch had operated a road-check t h e r e , d u r i n g the h u n t i n g season, a n n u a l l y s i n c e i 9 6 0 . " P o p u l a t i o n " i n t h i s study i s d e f i n e d as the group of grouse which l i v e on d e f i n e d s e c t i o n s of ground i n these l o c a t i o n s , d u r i n g the s p r i n g and summer months. I t was assumed t h a t r e l a t i v e l y l i t t l e mixing of b i r d s occurred between the are a s . Grouse tyave been banded at M.Q.L. and C.B. si n c e 1959 and 1962 r e s p e c t i v e l y , and no recover y has been made of a b i r d which d i s p e r s e d from one are a to the other. I t seems h i g h l y u n l i k e l y t h a t grouse i n any numbers t r a v e l the 100 m i l e s between the two f u r t h e s t p o i n t s . The p h y s i c a l geography and v e g e t a t i o n of M.Q.L. and C.B. are d e s c r i b e d by E l l i o t t ( 1 9 6 5 ) and Zwickel ( 1 9 6 5 ) and are summarized i n Table 1. The C O . study area ( P i g . 2) i s i n a northwest and southeast - o r i e n t e d v a l l e y , between low -6-- 7 -mountains immediately east of the principal mountain range of the island. The valley i s approximately seven miles by three i n extent. Tv/o areas on opposite slopes of the valley were chosen as the general study area (roughly 1600 acres), while a small plot on the southwest slope (41 acres) v/as chosen for more intensive study. The sides of the valley are intersected by numerous drainage gulleys and where these have been interrupted, small wet areas have developed. The flo o r of the valley i s r e l a t i v e l y f l a t and considerably altered by the stream i t hosts. The altitude of the area i s from 1500 to 2500 feet above mean sea l e v e l . A l l three areas are i n a similar climatic zone and had similar primaeval vegetative cover. They l i e at the junction of the coastal western hemlock (Tsuga heterophylla) and coastal Douglas f i r (Pseudotsuga menziesii), bioclimatic zones as described by Krajina (1965), (Table 1). The three have a history of clear-cut logging followed by slash burn and,at least one w i l d - f i r e . A l l three were re-planted with Douglas f i r seedlings. V/hen this study began, a l l areas bore vegetative cover which varied from bare ground,-logs and annuals, to low shrub and f i r one to ten years old. No detailed analysis of vegetation was carried out. Bendell & E l l i o t t (1967) concluded that blue grouse w i l l continue to recruit into habitat u n t i l the vegetation reaches a density of tree cover somewhat over 70^. A l l work was carried on i n areas with cover well below this value. I l l u s t r a t i o n s of the vegetative cover of the three areas can be found i n Appendix 1. ' -8-Figure 2. The Copper Canyon stu/ly area; -Si-Table 1. Summary of physical geography, climate and vege-tation of the study areas. Study nearest town acres area topography Altitude (feet) Aspect & mean slope Middle Campbell 832.2 Quinsam River, Lake B.C. (M.Q.L.) Comox Courtenay, 1500. Burn B.C. (C.B.) Copper Ladysmith, 1600 Canyon B.C. (41) (CC.) gently r o l - 900- n i l l i n g h i l l s , 1100 temporary ponds low r o l l i n g 700- 20-25C h i l l s and 1600 NE drainage gulleys run-ning NE valley walls 1500- 20-35C intersected 2500 NE by v-shaped & SW gulleys, wet areas (cont'd) mean ann. o r i g i n a l history present r a i n f a l l vegetation of veg. veg. (inches) previously studied 40-80 40-80 40-80 D„ f i r W. hem. W.R. cedar D. f i r 'W. hem. D„ f i r W. hem. V/.R. cedar Go f i r Clear- open-cut, burn v. open ci r c a 1945 planted planted D. f i r D. f i r 1958 clear- open-cut, burn v. open circ a I960 planted planted D.fir D0 f i r 1961 clear-cut , burn 1959-68 replanted D. f i r open-v. open planted D. f i r E l l i o t t , 1965 Bendell & E l l i o t t , 1966 Bendell & E l l i o t t , 1967 King, 196S Zwickel, 1965 Lance, 1967 Zwickel, Bendell, 1967 n i l , MATERIALS AND METHODS This study was carried out during the summers of 1967 and 1968. F i e l d work commenced May 4 both years and terminated August 1 0 , 1967 and August 3 0 , 1968. Two assis-tants made the coverage of the three areas possible. Ob-servers were moved between the areas to give coverage of a l l three by the same workers. a) Measuring the parameters and dynamics of the  populations This part of the f i e l d work v/as designed to measure population density, age structure of the breeders, survival of the breeders and the annual production of chicks up to f a l l . Census consisted of t o t a l counts of breeding males from repeated search of known acreages. The search was done by lone observers, each accompanied by a trained pointing dog. We searched a pattern that gave even coverage of the entire areas. Each bir d encountered v/as c l a s s i f i e d as to age and sex and marked on a base map. Color leg bands were used to identify individual birds. Census v/as aided by the use of recorded female c a l l s which induced singing i n males and made them easier to locate. For a more detailed description of the method of capture, banding and other f i e l d procedures, see Bendell ( 1 9 5 5 ) ; Zwickel ( 1 9 6 5 ) ; Zwickel & Bendell ( 1 9 6 7 b ) ; S t i r l i n g & Bendell (1966) and Appendix 1 0 . Prepared 3 " x 5" -11-data cards were used to standardize the numerical population data recorded during search (Appendix 2). At C.C., "li s t e n i n g stations: were established to supplement t o t a l search and to allow a check of the density of t e r r i t o r i a l males over a larger area. Sections of four logging roads were used as transects. Their lengths t o t a l l e d 9,235 yards, and the census effe c t i v e l y covered 100 yards on both sides of the roads. Listening stations were placed approximately 100 yards apart. These were v i s i t e d during May and June, between the hours of 0530 - 0900 and 1900 -2200, the times of d a i l y peaks i n song a c t i v i t y . In a single l i s t e n i n g period, one transect was covered i n entirety and each was covered at least 3 times per year. A car was used to move between l i s t e n i n g points and at each, after a 10 minute pause, a series of "whinny" c a l l s of the female grouse was broadcast. This method yielded an effective census of males along the roads ( S t i r l i n g & Bendell, 1966 and Appendix 3). A.ge structure and survival were determined from a pooled sample obtained by capturing unhanded birds on the study areas, by shooting birds nearby and by observing the number of banded birds from previous years. Grouse were aged as adults over two years or as yearlings, according to the roundness of the outer primaries (Boag, 1965). The number of chicks produced by each population an-nually was obtained by determining the average clutch size, by estimating the number of unsuccessful hens and by measur--12-ing the mortality of chicks over the summer. Chicks i n hand were aged by the method of Zwickel and Lance (1966)» How-ever, because chicks were not captured from the majority of broods, a method of aging at a distance was devised. This was based on aspects of contour feather, r e c t r i x and body development, and allowed placement of any chick into one of 6, 10-day age categories when compared to a series of sketches (Appendix 4). The B.C. Fish & Wildlife Branch cooperated by oper-ating road checks at M.Q.L. and C.C., on the opening days of the hunting season both years. In 1967, these were manned from September 9 - 1 1 and i n 1968, from August 31 - September 2. The number of birds shot per hunter per day was recorded along with the sex, age and weight of each grouse. b) Measuring behavior Only a limited amount of "undisturbed" behavior could be recorded. Blue grouse, because of thei r secretive habits, cannot be subjected easily to this kind of observation. How-ever, the song of undisturbed males was recorded whenever heardo The song was c l a s s i f i e d according to the number of syllables i t contained and how many songs were sung per min-ute. Singing v/as timed over a 5 minute period. Other sounds from undisturbed grouse were also recorded, but with low and uncertain frequency. These were not used i n analysis. Most data were obtained by presenting grouse with agonistic "situations". -13-The encounter between a grouse and a f i e l d worker was taken as such a situation. This consisted simply of a slow stalk toward a bird whose location had been indicated by a pointing dog. The response of the bird was quantified by recording a variety of measurements and observations on i t s movements and behavior. These included noting the occur-ence of behavior patterns which are known to have agonistic significance. In addition, i t involved a measurement of how "approachable" the bird was. The response of males to a r t i -f i c i a l song was noted. Hen "chick defense behavior" was rated according to the relative vigor they displayed, and the response of hens to a r t i f i c i a l chick "screaming" was also rated. Prepared 3" x 5" data cards standardized the data taken and helped standardize the presentation of the situation to the birds, (Appendix 9). The specific observations taken are best mentioned as the results are considered below. See also Appendix 10. The second situation was a "test arena" to which only males responded. In a small, f l a t clear area three plate glass mirrors 4-0 cm x 60 cm, and a stuffed dummy hen blue grouse were arranged. Amplified hen c a l l s could be played from a speaker concealed by the mirrors. The mirrors were stood on t h e i r long edge, supported by blocks and arranged i n a triangle with th e i r faces outward. The hen, stuffed i n the "squatting position" was placed opposite one of the faces of the mirrors, and about half a meter from i t . The speaker of a portable amplifier (Wightman E l e c t r i c , model C.W. - 6) was -14-positioned i n the center of the mirrors and the lead was run to a hide approximately 15 meters away. This apparatus was set i n the approximate center of a male's t e r r i t o r y . When the hen "whinny" was played, the cock was enticed to approach and court the dummy, thereby he was 'forced' to i n t e r a c t v/ith h i s mirror image. His r e -sponse was recorded by making a tape recording of a l l h i s behavior as i t occurred. I t was q u a n t i f i e d by measuring the time from h i s a r r i v a l u n t i l c e r t a i n aggressive patterns were observed and by counting the number of aggressive acts per-formed per minute. Appendix 12 gives a more d e t a i l e d d e s c r i p -t i o n of the apparatus and the method f o r presenting i t to males. This t e s t v/as given to a sample of 40 cocks at M.Q.L. and C.C. while at C.B. 10 v/ere tested. These were chosen i n an even manner throughout the study areas. Tests were given i n the periods from 0500 - 1000 and 1800 - 2200, the peaks of t e r r i t o r i a l song during the months of May and e a r l y June. Analysis i n most cases involved compiling the number of s i t u a t i o n s i n which a p a r t i c u l a r type of behavior was recorded and t e s t i n g f o r d i f f e r e n c e s between areas by c h i squared t e s t s . When the data were of the kind that permitted c a l c u l a t i o n of mean and standard deviation, t h i s was done. Whenever s i g n i f i c a n c e i s i n d i c a t e d , unless otherwise stated, t h i s i s at l e a s t at the 95$ confidence l e v e l . -15-RESULTS Population densities and trends The densities of blue grouse on the three areas were measurably different during t h i s study (Fig. 3). The C C population, at approximately 35 singing males per hundred acres, was about 6 times as dense as the M.Q.L. population which had approximately 6 singing males per hundred acres. This, i n turn* was s l i g h t l y more dense than the C.B. popul-ation which had approximately 5 singing males per hundred acres. The trends of the populations were obtained by incor-porating the results of previous studies (at M.Q.L. and C.B.) and a roadside sample of hunters (at C C ) , (Pig. 3). This showed that M.Q.L. was i n a slow decline which appears to have begun i n 1964-. This decline was approximately 10$ per year and was continuing at the time of this study. C.B. was re-maining stable. C C had increased since 1964-. This appar-ently ended i n 1968. The increase was approximately 12$ per year. These findings, confirmed the impressions pr i o r to the study, that the populations differed i n trend. The increase i n numbers at C C ceased during the study. Annual mortality and age structure of breeders The age structures of the breeding grouse i n the three -16-F i g u r e 3 . The d e n s i t i e s o f b l u e g r o u s e , 1 9 6 2 - 6 8 . ( P o i n t s p r i o r t o 1 9 6 7 a t M.Q.L. and C.B., 'from Z w i c k e l , 1 9 6 5 ; E l l i o t t , 1 9 6 5 ; L a n c e , ( u n p u b l i s h e d ) and B e n d e l l ( u n p u b l i s h e d ) . ) 40 UJ O < 30 Q UJ' e_ O 2 3 X UJ a. cn UJ < 2 < E o E K Ul I -20 10 1962 1963 1964 1965 1966 1967 1968 -17-areas d u r i n g 1967 and 1968 are shown i n T a b l e 2. I n b l u e grouse, the female segment o f the b r e e d i n g p o p u l a t i o n o f f e r s the o n l y measure- o f age s t r u c t u r e because, u n l i k e the males, t h e y are j o i n e d each s p r i n g by a l l the r e c r u i t s from the p r e v i o u s y e a r s ' p r o d u c t i o n . I t must be assumed t h a t the male segment o f the p o p u l a t i o n has a s i m i l a r age s t r u c t i i r e . Only two age c l a s s e s can be r e c o g n i z e d - ' y e a r l i n g s ' under 15 months, and ' a d u l t s ' o v e r t h a t age. T h e r e f o r e , age s t r u c t u r e i s e x p r e s s e d s i m p l y as the p e r c e n t o f the female segment which was made up by y e a r l i n g s . T a b l e 2. P e r c e n t y e a r l i n g females among hens M.Q.L. C.B. CO.. p e r c e n t sample y e a r l i n g s i z e p e r cent y e a r l i n g sample s i z e p e r cent y e a r l i n g sample s i z e 1967 25.2 (91) 44.2 (63) 40.0 (20) 1968 30.6 (85) 40.0 (70) 34.8 (146) Age s t r u c t u r e v a r i e d most i n 1967, from a low o f 2 5 $ y e a r l i n g a t M.Q.L. to a h i g h o f 44$ y e a r l i n g a t C.B. I n 1968, a l l areas showed about 30 - 40$ y e a r l i n g . By C h i squared, none o f the d i f f e r e n c e s between y e a r s o r between areas v/as s i g n i f i c a n t . However, when y e a r s were lumped, M.Q.L. emerged s i g n i f i c a n t l y lower than the o t h e r tv/o a r e a s . -18-Hence, i n a l l populations, there was suf f i c i e n t re-cruitment to allow for mortality of approximately 30 - 4-0$ among the breeders and s t i l l maintain s t a b i l i t y . At M.Q.L., recruitment was consistently at, or s l i g h t l y below the 30$ required for s t a b i l i t y of this population i n the past (Bendell & E l l i o t t , 1967). Breeding males, because they return to the same ter-r i t o r y each year, offer a good measure of annual mortality among adults. However, because the males must be banded i n order to make this measurement and because v i r t u a l l y no. birds, v/ere banded at G.C, i t was calculated only for M.Q.L. and C.B. (Table 3). Table 3. Annual mortality of breeding males. Study area: M.Q.L. C.B. 1966: number banded: 35 38 1967: number returned: 22 • 28 $ mortality: / 25.7$ 26.3$ t o t a l banded: 34 38 1968: number returned: 17 20 $ mortality: 50.0$ 47.4$ -19-Th. ere was no s i g n i f i c a n t d i f f e r e n c e between areas e i t h e r w i t h i n y e a r s or throughout the study when both y e a r s ' d a t a were lumped. However, p o o l i n g the d a t a from bo t h study a r e a s and comparing y e a r s , the apparent d i f f e r e n c e p r o v e d s i g n i f i c a n t . I t appears from t h i s t h a t a d u l t mor-t a l i t y s t r u c k e q u a l l y a c r o s s the p o p u l a t i o n s . I t was a v e r -age i n 1967 (25 - 35$)1 comparing f a v o r a b l y w i t h t h a t r e -p o r t e d i n the p a s t ( B e n d e l l , 1 9 5 5 ; E l l i o t t , 1965; Z w i c k e l , 1965), but i t was s i g n i f i c a n t l y h i g h e r i n 1968, (47 - 50$). Comparing r e c r u i t m e n t and a d u l t m o r t a l i t y between the p o p u l a t i o n s over the p e r i o d o f the stu d y : a t M.Q.L. an average o f 43$ of the b r e e d e r s d i e d a n n u a l l y and was matched w i t h a r e c r u i t m e n t o f 28$. At C.B., a comparable 37$ of br e e d e r s d i e d a n n u a l l y but was o f f s e t by a h i g h e r average r e c r u i t m e n t of 42$. At C.C., the grouse d e n s i t y a p p a r e n t l y r o s e i n 1967 ( P i g . 3) and l e v e l l e d o f f i n 1968. Meanwhile i t showed a h i g h t o medium r e c r u i t m e n t (37$). T h i s i n d i c -a t e s t h a t a d u l t m o r t a l i t y somewhat s i m i l a r t o t h a t observed a t M.Q.L. and C.B. must have o c c u r r e d t h e r e . From t h i s I conclude t h a t t h e r e was no obvious d i f -f e r e n c e i n the death r a t e o f b r e e d e r s t h a t c o u l d e x p l a i n the d i f f e r e n c e i n r e c e n t t r e n d s o f the p o p u l a t i o n s . There was a s l i g h t d i f f e r e n t i a l r e c r u i t m e n t between them. M.Q.L. appeared t o show a c o n s i s t e n t l y lower r e c r u i t m e n t than the o t h e r a r e a s . T h i s c o u l d be r e l a t e d t o the slow d e c l i n e o f t h a t p o p u l a t i o n . -20-Production For the purpose of this study, production was defined as the number of chicks that survive i n a population per breeding adult female, up u n t i l the grouse migrate from their breeding range. A surplus of chicks over the number re-quired for recruits the next year, has been produced an-nually i n a l l blue grouse populations, studied to date on Vancouver Island (Bendell, 1 9 5 5 ; Zwickel, 1 9 6 5 ) . This has r led to the hypothesis that some process must adjust the numbers of these chicks, during the period between breeding seasons. Given that a l l females participate i n breeding (Zwickel & Bendell, 1 9 6 7 ) , the survival of eggs and young are the pr i n c i p a l causes of variation i n production. I t can thus be treated under two subheadings: the number of brood-less hens, producing no chicks at a l l , and the number of chicks that are produced by the "successful" hens. a) Broodless hens This can result from nest depredation, nest desertion and complete loss of broods after hatch. A r a t i o of the number of broodless hens to brood hens, observed i n the months of July and August, was used to estimate this para-meter. At C.G. i t v/as not possible to determine the rat i o using banded birds. Therefore, because I v/as interested more i n a comparison between areas than i n an absolute measure of broodlessness, I used sightings of a l l hens i n ' a l l areas, -21-treating each new sighting as an unknown. This probably-introduced certain biases because of the different behavior of lone and brood hens (Zwickel, 1965; and below). To elim-inate t h i s , a correction factor was determined from the re-sighting frequencies of banded lone and brood hens at M.Q.L. and C.B., during July and August. The rat i o was i n favor of resighting brood hens 1:1.9. It assumed that the chance of resighting any individual hen was a random event. The adjusted r a t i o of a l l broodless hens to brood hens was then calculated, (Table 4). Table 4. The number of broodless hens by area and year. Study area: M.Q.L. C.B. CC. 1 9 6 7 sightings of broodless hens 72 10 12 sightings of brood hens 106 42 136 Corrected per cent broodless: 56.3$ 3 1 . 3$ 14.3$ 1968 sightings of broodless hens 40 6 26 sightings of brood hens 126. 21 1 0 3 Corrected per cent broodless: 37.7$ 35. 3$ 32.5$ Comparing populations, a l l were s i g n i f i c a n t l y different i n 1967. with M.Q.L. showing the highest proportion of brood-less hens and C C the lowest. In 1968, no difference could - 2 2 -be demonstrated between any of them. Comparing years, M.Q.L. had si g n i f i c a n t l y more broodless hens i n 1967 than i n 1968, while C.C. showed more broodlessness i n 1968 than 1967. C.B. showed no difference between years. Thus, there was a maximum of 56$ and a minimum of 14$ broodless hens i n the populations. Note that 1967 was a year of ex-tremes. That year, M.Q.L. had the lowest number of success-f u l hens recorded, while C.C. had the highest number re-corded. These data indicate that hen f a i l u r e was highly var-iable and struck independently across the areas. The values compare favorably with those reported by Zwickel (1965) who showed a maximum of 50$ and a minimum of 15$ broodless hens at C.B., M.Q.L. and Wolf Lake over the years 1962-64. Therefore the differences noted above are probably best explained as normal chance variations. The cause of hen fa i l u r e was also compared across the areas. The fate of a l l nests located was determined (Table 5). Because of the d i f f i c u l t y i n finding grouse nests, the two years' data were lumped for a more meaningful com-parison between areas. Table 5 . Fate of n e s t s , 1967-68 Study area M.Q.L. C.B. C C . number n e s t s found 7 7 7 d e s e r t e d 0 1 0 depredated 3 3 1 Per cent l o s s 4 3 $ 5 7 $ 14$ Although these nests were d i s t u r b e d as l i t t l e as p o s s i b l e w h i l e t h e i r p r o gress was f o l l o w e d , t h e r e i s no way to estimate how our d i s c o v e r i n g them a f f e c t e d t h e i r s u r v i v a l . The val u e s shown are probably maximum f o r t h i s reason. Note t h a t the l o s s f a l l s i n the 14 - 5 0 $ range and t h a t t h i s com-pares f a v o r a b l y w i t h the number of u n s u c c e s s f u l hens. The apparent d i f f e r e n c e between C C and the other two areas i s not s i g n i f i c a n t by c h i squared. P o o l i n g a l l areas, 38$ of ne s t s l o c a t e d d u r i n g the study were u n s u c c e s s f u l . b) Chicks r a i s e d by s u c c e s s f u l hens To determine the number of c h i c k s r a i s e d by each s u c c e s s f u l hen, broods were p l a c e d i n t o 10-day age groups and the a g e - s p e c i f i c brood s i z e was c a l c u l a t e d f o r each area ( P i g . 4 ) . C l u t c h s i z e was determined from l o c a t e d n e s t s . Since no s i g n i f i c a n t d i f f e r e n c e was found between areas or between y e a r s , a l l c l u t c h e s -24-were lumped. The mean s i z e o f c l u t c h was 6.2 (n : 2 l ) . The graph compares the p a t t e r n o f c h i c k m o r t a l i t y f o r each a r e a through the summer, and shows the mean number of c h i c k s a l i v e p e r brood, a t the end of each age i n t e r v a l . In g e n e r a l , C.C. r e t a i n e d numbers b e t t e r , over the summer, than M.Q.L. C.B. showed an i n t e r m e d i a t e l o s s . The p a t t e r n of c h i c k d i s a p p e a r a n c e was b a s i c a l l y the same, how-ever; an i n i t i a l h i g h m o r t a l i t y u n t i l 10 days, was f o l l o w e d by a slower, more c o n s t a n t l o s s . T h i s compares f a v o r a b l y w i t h t h a t r e p o r t e d a t Lower Quinsam Lake by B e n d e l l (1955a) and a t C.B. by Z w i c k e l (1965). The d i f f e r e n c e i n s u r v i v a l between M.Q.L. and C . C , by the 50 - 70 day i n t e r v a l , was s i g n i f i c a n t i n bo t h 1967 and 1968. W i t h i n any one p o p u l a t i o n however, t h e r e was no s i g n i f i c a n t d i f f e r e n c e i n brood s i z e , between y e a r s , a t 50 - 70 days. A l s o no d i f f e r e n c e . c o u l d be shown between C.B. and e i t h e r o f the o t h e r two a r e a s , i n any one y e a r . Both y e a r s ' d a t a f o r each a r e a v/ere then summed t o determine the average annual p r o d u c t i o n from s u c c e s s f u l hens ( T a b l e 6). T a b l e 6. Average s i z e o f day, age c l a s s ) broods i n f a l l , • ( 5 0 -• 7 0 Study a r e a M.Q.L. C.B. C.C. 1967 3.4 i 1.3 (3.6) 5 . 0 - 0 .9 1968 2.4 ± 0 . 5 (3.8) 4.7 i 1.3 .A. V € I* Q. G brood s i z e 2.8 - 0.8 (3.7) 4.9 - 1.0 -25-F i g u r e 4 . Mean b r o o d s i z e s a t 10 day i n t e r v a l s o f age (1967-68). 1 J L J L_ J l l 0 10 20 30 40 50 60 AGE OF BROOD IN DAYS If the number of broodless hens i s taken as the max-imum observed (56 per cent), and the 44 per cent remaining produced the minimum number of chicks to f a l l (2), i n a pop-ulation of 100 hens, a t o t a l of 88 chicks would be produced. Given a 50:50 sex r a t i o , t h i s would be the output from 200 breeding adults. Since adult mortality i s approximately 30$ per year, or 60 from these 200, there seems to have been a surplus of chicks produced, even i n the worst years. How-ever, i t i s possible that with the high adult mortality suffered at M.Q.L. i n 1968, 100 chicks would have been re-quired for r e c r u i t s . On the other hand, i f the average annual production shown i n Table 6 i s more r e a l i s t i c than the minimum, even thi s loss could have been made up with a 6 per cent surplus. Therefore, even though differences occurred i n pro-duction between areas and between years, with the possible exception of M.Q.L. i n 1968, more than sufficient chicks were raised i n a l l areas, both years, to compensate for adult mortality. Summary of population results 1. The density of t e r r i t o r i a l males per 100 acres was 35 at C.C., 6 at M.Q.L. and 5 at C.B. 2. M.Q.L. appeared to be declining at 10$ per year, C.B. was stable and C.C. appeared to have undergone a 12$ per year increase which ended i n 1968. 3 . A l l populations were 2 5 -40$ yearling. The population at M.Q.L., over the two years, contained fewer yearlings than the other areas. 4. The annual mortality of adult males was 26 - 5 0 $ at M.Q.L. and C.B. Mortality was higher i n 1968 than i n 1967. These conclusions were l i k e l y v a l i d for C.C. as well. 5 . 1 4 - 5 6 per cent of hens i n a l l areas were brood-less. Most broodless hens were probably caused by nest f a i l u r e . 6. Brood hens at M.Q.L. raised 2.8 - 0.8 chicks each while at C.C. they raised s i g n i f i c a n t l y more, 4.9 - 1.0. At C.B. they raised an average of 3 * 7 . Behavior The data on behavior w i l l be presented i n three sec-tions: "Spontaneous" behavior was behavior which was not i n -duced by the observer or any apparatus. "Census-contact" behavior was observed during encounters between humans and grouse. F i n a l l y , "test arena" behavior was the result of subjecting grouse to the test arena. a) Spontaneous behavior "Hooting" i s the t e r r i t o r i a l song of the male blue grouse and the most obvious evidence of t e r r i t o r i a l behavior. There was evidence that males hoot less i n sparse populations (Bendell & E l l i o t t , 1 9 6 7 ) . -28-To compare the amount of hooting among the populations, an estimate of the relative number of males participating, was used. Counts were made of a l l sile n t males and of males i n continuous "broadcast" song, (as opposed to males which hooted i n response to us). The ratio of hooting to s i l e n t males, was determined from a l l males located during each month, throughout, the summer. The r a t i o obtained for the month of May was then set at 100$, as v i r t u a l l y a l l ter-r i t o r i a l males participate i n singing at that time. The per cent participating i n June, July and August were then de-termined for each area (Fig. 5 ) • There was no significant difference between years, i n the amount of hooting by this measure, so the two years were pooled. In June there was no significant difference between the populations. However, i n July, C.C. showed s i g -n i f i c a n t l y more hooting than either of the other areas. In August of both years, 24$ of the males at C.C. were s t i l l hooting, while no hooting v/as heard at C.B. or at M.Q.L. This tendency for C.C. males to persist i n hooting longer into the season than those at C.B. or M.Q.L., agrees i n part • with the findings of Bendell & E l l i o t t . (1967). Hooting v/as also examined for variation i n the number of songs per minute. Males were timed i n continuous song for periods of 5 minutes. Songs were eliminated i f the male was known to be i n the immediate v i c i n i t y of a female or another male - conditions which could alter the 'normal* rate of song. - 2 9 -- 3 0 -A l l areas showed the same rate of singing by this measure - sl i g h t l y over 5 per minute, (Table 7 ) . Table 7 . Number of songs sung per minute at C • C •, C.B* and M.Q.L. M.Q.L. C.B. C.C. n ( 3 3 ) ( 1 2 ) ( 6 5 ) 2 2 3 2 6 songs 5 13 5 17 1 1 9 per 5 18 7 1 1 7 minute 3 __«i»«-oo«0 X 5 . 1 7 5 . 0 1 The song of the blue grouse consists of low-frequency hoots i n single-toned syllables, given i n a series which usually does not vary from six (Bendell & E l l i o t t , 1967). ( S t i r l i n g (1965) describes hooting and gives a sonogram of the sound.) , In the present study, we counted the number of syllables i n songs during broadcast hooting. The songs of males near other birds were treated separately. The results from 1967 and 1968 were pooled. At least two song types were frequently used (Table 8). The six syllable type accounted i n a l l populations, for about 80$ of the songs heard, while the five syllable type accounted for most of the remainder. Two, three, four and -31-seven syllable songs were heard infrequently. Table 8 . Number of syllables i n blue grouse songs No. M.Q.L. C.B. C.C. syllables i n song Normal Near an. Normal Near an. Normal Near an. song grouse song grouse song grouse (n:266) (n:22) (n:145) (n:10) n:124) (n:22) 2 0.4(#) 3 0.4(#) 4- . . . . 0 . 8 O ) 5 . . . . 1 7 . 7 ( $ ) 2 7 . 0 6 68.6(#) 46 .0 7 1.909 5 . 0 5 & 6: 6 & 7 (mixed songs) 1 0 . 2 ( 9 9 2 3 . 0 14.0 82.0 9 . 0 88.0 2 . 0 7 . 0 8 7 - 0 4.0 9 . 0 4.0 3 6 . 0 5 0 . 0 5 . 0 1 0 . 0 There was no difference between the populations i n the di s t r i b u t i o n of these song types. However,' s i g n i f i c a n t l y more 5-syllable songs were heard when the cocks were near other birds. Also there seemed to be (although significance could not be demonstrated) more "mixed" songs used near other birds than during normal broadcast hooting. I t i s l i k e l y that song i n a l l areas was "set" at the 6-syllable type, but when a male was involved i n another a c t i v i t y such as seeking out another bir d , the song became variable. b) B e h a v i o r o f grouse i n response t o o b s e r v e r In g e n e r a l , t h r e e measures were taken, o f b e h a v i o r we observed d u r i n g census, i ) The e f f e c t o f b e h a v i o r on the s u c c e s s o f our census t e c h n i q u e , i i ) the f r e q u e n c y w i t h which we observed i n t r a s p e c i f i c b e h a v i o r p a t t e r n s and i i i ) d i f f e r e n c e s i n the p r e d a t o r escape b e h a v i o r used toward u s . i ) The su c c e s s o f the census t e c h n i q u e depended upon s i g h t i n g and c l o s e l y o b s e r v i n g grouse on the ground b e f o r e t h e y f l e w . . (See Z w i c k e l , 1965.) As a measure o f the e f f e c t i v e n e s s o f thes e census methods, the number of b i r d s encountered which were seen b e f o r e f l u s h i n g , the number which were seen i n f u l l view, and the number t h a t c o u l d be c a p t u r e d , were a l l compared between p o p u l a t i o n s ( F i g . 6; Ta b l e 9)• In no p o p u l a t i o n was t h e r e a s i g n i f i c a n t d i f -f e r e n c e between y e a r s . T h e r e f o r e the da t a o f both y e a r s v/ere summed. Between p o p u l a t i o n s , t h e r e was no demonstrable d i f f e r e n c e , between M.Q.L. and C.B. There was a s i g n i f i c a n t d i f f e r e n c e between C.C. and the o t h e r two i n eve r y c a s e , when the r e s p e c t i v e age and sex groups v/ere compared. The b i r d s a t C.C. were l e s s o b s e r v a b l e and l e s s approachable t h a n those a t the o t h e r a r e a s . Table 9 . Successful capture attempts with noosing pole, $ of t o t a l attempts,.1967-68 Study area M.Q.L. C.B. C.C. T e r r i t o r i a l males attempts: 1 0 2 80 54 $ success: 24 .5$ 28.8$ 8 . 3 $ Silent males attempts: 3 9 42 2 5 $ success: 12.8$ 4 5 . 2 $ 0 Brood females attempts: 28 1 9 3 9 $ success: 7 5 . 0 $ 9 4 . 7 $ 3 5 . 9 $ Lone females attempts: 4 7 3 9 2 $ success: 40 . 4 $ 5 1 . 3 $ 0 Roughly 60$ of a l l birds encountered at these l a s t two areas could be observed to some degree on the ground, and of these 3 0 $ could be captured. By contrast, only about 1 5 $ of birds encountered at C.C. could be observed, , and only about 2 0 $ of those observed could be captured. These results were l i k e l y caused by a combination of factors. However, assuming the same technique was used i n a l l areas, behavioral differences between the various . populations i s the simplest explanation. The additional measures taken below, asked more s p e c i f i c a l l y what these d i f ferences were. -34-F i g u r e 6 . Number of grouse seen before f l u s h i n g as a °/o of t o t a l encountered. M Q U 0 0 d C B C C MALES FEMALES MALES FEMALES MALES FEMALES Populat ion trend: DECREASING STABLE INCREASING - 3 5 -i i ) "Intraspecific" behavior toward observer This section includes a l l behavior which i s known to have some specific function i n encounters between grouse. Auditory signals v/ere frequently recorded while we stalked grouse. One important sound we e l i c i t e d from the cocks, was the t e r r i t o r i a l song. Often hooting was begun i n ap-parent response to us. Moreover, humans can make a reason-able imitation of the male's hooting and this seemed to accentuate the response. We hooted at 9 8 males and ob-served their response (Table 1 0 ) . In a l l populations, 2 5 - 3 0 $ of males made no obvious response. The response of cocks at M.Q.L. and C.B. were very similar. However at C.C, s i g n i f i c a n t l y more'birds either moved away or stopped sing-ing than did so at the other areas. In addition, whereas at M.Q.L. and C.B., 30 - 3 5 $ of males either increased hooting intensity or gave the "feather spread display", at C.C t h i s never happened. In general, cocks at C.C. sang less frequent-l y i n response to a r t i f i c i a l hooting. Table 1 0 . Response of t e r r i t o r i a l males to observer and a r t i f i c i a l hooting, 1 9 6 7 - 6 8 . Study area: M.Q.L. C.B. C.C. sample size: (40) (34) (24) Response 1 . 0 0 42$ 2 . 5 $ 9 $ 3 3 $ 3 . nil..remain s i l e n t or . 3 3 $ 3 2 $ 2 5 $ 4. start singing or increase 3 3 $ 26$ o: 5 . feather spread or approach 3 0 $ 3 2 $ 0 Another social signal of the blue grouse which may have a somewhat similar function to hooting, i s a loud wing f l u t t e r which they can give upon alighting. Bendell & E l l i o t t ( 1 9 6 7 ) describe this as the " f l u t t e r f l i g h t " and think i t . i s a t e r r i t o r i a l signal equal to song. Blackford ( 1 9 6 3 ) des-cribes a similar sound i n the dusky grouse (Dendragapus  obscurus obscurus) and concludes that i t i s a form of "ter-r i t o r i a l drumming". I compared the number of birds which gave the sound after flushing from us, (Table 1 1 ) . Table 11. Number of birds giving " f l u t t e r f l i g h t " when flushed, 1967-68, i n per cent. Study area M .Q.L. C.B. C .c. Cn) % {n) $ 25-9 (189) 9.6 (115) 6.8 (136) 6.0 (117) 1.4 (72) 5- 2 (154) Brood hens 20.9 (115) _ _ _ _ 0.9 (103) 0.0 (118) 1.0 (97) 0.0 (57) There v/ere s i g n i f i c a n t l y more f l u t t e r s made by both t e r r i t o r i a l males and brood females at M.Q . L . , than by males at the other tv/o areas. Among sil e n t males and lone females, less than 6 per cent gave this sound, and no difference be-tween populations could be demonstrated. The threatening or "attack intention" c a l l s of both sexes are usually observed only i n highly aggressive birds, immediately prior to attacking. These include the "growl" or "ca-ca" threat c a l l of the male ( S t i r l i n g , 1965; S t i r l i n g & Bendell, 1970), female cluck ( S t i r l i n g , 1965), and "qua-qua" cry of the female ( S t i r l i n g , 1965). These sounds-were heard only very infrequently during the f i e l d work. In 100 ob-servations of grouse of both sexes i n each area, at M.Q .L . they v/ere heard 5«1 times, at C.B. 4.3 times and at CO. only 0.4 times. 3 8 -Blue grouse also have many, visual signals which they use i n intraspecific situations. I t was .noted how grouse differed i n the ease with which we could observe them. Some grouse, when encountered by humans, use behavior which seems to have the purpose of reducing v i s i b i l i t y . This behavior ("crouch and run", Appendix 7 ) was observed i n yearling males when near t e r r i t o r i a l cocks, and i n a variety of grouse, when being pursued by us, (Fig. 7 ) . There was no s i g n i f i c -ant difference between grouse at M.Q.L, and C.B., i n the numbers showing thi s behavior. In a l l cases, however, com-paring the sex and age categories separately, birds at C.C. showed the behavior s i g n i f i c a n t l y more often, than those at either of the other areas. The "feather spread" or "sexual display" ( S t i r l i n g , 1 9 6 5 ) i s the most obvious visual signal of the blue' grouse. S t i r l i n g described i t and concluded that i t functions pr i n -c i p a l l y i n sex advertisement. The display seems to take over where song and f l u t t e r f l i g h t s end, i n advertising a male's ownership of t e r r i t o r y . Males using this display toward us may have been acting more aggressively than males who did not (Hg'orth, 1 9 6 7 ;. Lumsden, 1 9 6 5 ) . At M.Q.L. and C.B., 3 5 - 3 7 $ of a l l adult males seen gave the feather spread, while at C.C., 1 1 $ did so (Table 1 2 ) . This difference be-tween C.C. and the other tv/o areas i s s i g n i f i c a n t . No s i g -nificant difference could be shown between M.Q.L. and C.B. Variations i n the degree of display may also be mean variations i n aggressiveness. The intensity of display i n - 3 9 -F i g u r e 7 . Grouse showing " c r o u c h and run" b e h a v i o r i n p e r c e n t . c z 3 C "O c n 75 -S O 3 O 50 K O C3 2 o _: CO 25 UJ 63 § 2 n: 197 singing 25 silent I 39 lone 99 brood 89 26 singing si|ent 26 lone 16 brood silent |on~ singing MALES FEMALES POPULATION: Q L D E C R E A S I N G MALES FEMALES C B STABLE 70 73 191 30 brood MALES FEMALES C C INCREASING -4Q-each instance was rated on a scale from 1 - 3 . according to the amount of t a i l fan, neck pouch display, and eye comb coloration. The average intensity of display by this measure, at M.Q.L. and C.B., was 1.6 - 1.7 with no significant d i f -ference between them, while at C.C. no bird rated above 1.0. Table 12. Number of observer, adult males which displayed toward 1967-68, i n per cent. Study area M.Q.L. C.B. C.C. n: (139) (130) (37) % displayed: 36.7 34.6 10.8 Gestures signifying direct aggression and attack i n -tention were also observed. These included "neck stretching" and "head dipping" - both highly aggressive patterns, seen immediately before an attack i s made on a mirror or another bird (Appendix 8). The two patterns were treated together (Table 13). They were observed every 12 - 16 encounters at M.Q.L. and C.B., whereas at C.C. they were observed only once every 30 encounters with grouse. Again, the difference between C.C. and the other two areas i s si g n i f i c a n t . -41-Table 13. Neck stretching or head dipping observed i n 100 encounters, 1967-68. Study area M.Q.L. C.B. C.C, no. times observed: 8.1 5.7 0.3 Predator avoidance behavior This behavior functions primarily i n the interspec-i f i c sense. "Flushing" i s the most obvious predator avoid-ance behavior. The "flushing distance" or distance between the observer and grouse when i t flew, was used to quantify the response, (Fig. 8). Again there was no significant d i f -ference between M.Q.L. and C.B. Flush distances were s i g n i f -icantly longer at C.C. i n each sex and age category, except the lone female class. A related phenomenon was the "reluctance" of birds to f l y from us. Thi's was measured by the time i t took for a grouse to flush, and the distance i t walked- or-ran before flushing (Table 14). Note that M.Q.L. and C.B. again re-sembled one another. Comparing C.C, i n each category s i g -n i f i c a n t l y fewer birds took over 2 minutes to flush and fewer moved over 20 meters, than those at the other areas. Brood defense behavior, displayed by brood hens, probably functions solely as a response to predators. Bendell & E l l i o t t (1967) describe this behavior from the f i e l d . F i g u r e 8. F l u s h i n g d i s t a n c e s a t M.Q.L., C.B. and C.C. Table 14. "Reluctance" to flush. Distance grouse moved on ground before flushing and the time from f i r s t disturbance to flushing, 1967-68. A. Time to flush. {% of encounters where bird took over 2 min.) Study areas M.Q.L. C.B. C.C. MALES singing: 5 0 . 1 41 .8 0 (n : 2 0 2 ) ( n : l 2 2 ) ( n : l 2 3 ) s i l e n t : 2 3 . 8 1 1 . 8 0 (n : 1 0 7 ) (n : 6 8 ) (n : 1 5 3 ) FEMALES brood: 35«4 41.4 14.0 (n : 1 3 3 ) ( n : l l ) (n:?l) ( n : l l 9 ) (n : 6 3 ) (n : 5 7 ) B. Distance moved on ground. {% that moved over 2 0 meters.) MALES singing: 3 6 . 2 2 3 . 5 1 . 0 (n:256) (n : 1 5 7 ) ( 1 3 9 ) s i (n:!24) (n : 7 8 ) (n:154) FEMALES brood: ........... 3 2 . 8 36.4 1 9 » 5 (n:148) (n : 2 2 ) (n : 1 1 3 ) (n : 1 3 7 ) n:80) (n : 5 7 ) Two basic elements were recognized i n thi s behavior: an attempt by the female to lead us (the predator) away, and an intimidating rush toward us. In the former, movement was -44-generally away from the enemy and i n the l a t t e r , movement was generally toward i t , culminating at times with contact. Again, M.Q.L. and C.B. resemble one another (Table 15). At C.C. there was s i g n i f i c a n t l y less leading and rushing than at the other areas. Table 15. Brood defense behavior. The number of brood hens i n per cent, which showed "leading" and/or "rushing", 1967-68. Study area M.Q.L. C.B. C.C. n: (280) (74) (256) leading 98.5 99.2 35.5 rushing at 77.4 58.1 4.1 In 1968 the response of hens during leading and rush-ing v/as given a rating on a predetermined scale. Three cate-gories were devised for each display, according to the near-ness of approach to the observer, degree of feather spread, amount of vocalization, and general vigor of the response. The mean index for each population v/as calculated (Table 16). Following the i n i t i a l encounter with brood hens, their brood defense was further rated by recording their response to a r t i f i c i a l "chick c a l l i n g " . (By whistling through the teeth, humans can produce a reasonable imitation of a young chick i n distress.) Again, the mean index of their response was - 4 5 -determined for each area (Table 16). Table 16. Vigor displayed by hens i n brood defense behavior toward observer. Study area M.Q.L. C.B. C.C. Mean score (n : 1 5 0 ) (n : 3 0 ) (n : 1 1 3 ) 1 . 7 0 . 7 Mean score (n : 1 5 0 ) (n : 3 0 ) (n : 113) (intimidation) .... 1 . 3 1 .1 0 . 2 Mean score (response to chick (n : 1 3 7 ) (n : 2 7 ) (n : 1 0 9 ) 1 .1 0.6 There were significant differences between a l l popula-tions i n the mean index of predator intimidation. The index of vigor for leading did not vary between M.Q.L. and C.B., but i t was s i g n i f i c a n t l y lower at C.C. than at either of the other areas. Hens at C.C. apparently defended their chicks less vigorously than hens at either M.Q.L. or C.B. Chick behavior was also p r i n c i p a l l y a predator escape response. C r i t i c a l evaluation of chick behavior was possible only i n 1968 and was only done at M.Q.L. and C.C. The co-hesion of undisturbed broods was measured by noting the dis-tance of individual chicks from the hen, when the broods were f i r s t discovered (Fig. 9). Note that C.C.- chicks v/ere consistently found farther from their hen than chicks at M.Q.L. F i g u r e 9 . D i s t a n c e u n d i s t u r b e d c h i c k s were observed from hen. E 22 u. z UJ 20 95Z C L . 90l C L . § o ct u. mean I 18 Q UJ > UJ £fl 16 Cfl O E u UJ o z 14 12 h-f MQL C C The behavior of chicks at the moment of disturbance was c l a s s i f i e d into three types of response: "scatter and hide under", "crouch and flush", and "flush immediately". Chicks were divided into three age groups, 1 - 2 , 3 - 4 , and 5 - 6 weeks; each group was treated separately (Pig. 1 0 ) . Note that at every age, differences occurred i n the behavior of chicks between the two areas. A l l differences were s i g -n ificant except at age 1 - 2 v/eeks when the proportions that flew immediately, were not different. Of those that did f l y , however, the number of chicks at C.C. that flew over 50 meters (Table 1 7 ) was si g n i f i c a n t l y greater than at M.Q.L. i n a l l age classes. An obvious feature of these results i s that as they aged, chicks at M.Q.L. showed a low and de-creasing proportion, which flushed immediately, while those at C.C. showed a high and increasing proportion which did so. More chicks at M.Q.L. "crouched and flushed" when disturbed, especially i n the older age classes, while at C.C. a smaller and r e l a t i v e l y fixed number did. At M.Q.L., si g n i f i c a n t l y more chicks displayed the "hide under" behavior and th i s persisted into the older age classes, while at C.C. no chicks at the older ages used this behavior. The meaning of these behavior patterns i s not known. Chick behavior may have paralleled adult behavior; adults at M.Q.L. showed the same reluctance to flush. -47a-F i g u r e 1 0 . B e h a v i o r of c h i c k s when d i s t u r b e d by o b s e r v e r . * - Numbers show per cent u s i n g type of b e h a v i o r . -48-Table 1 7 . Number of chicks i n per cent which flew less than 50 meters when flushed. Study area M.Q.L. C.C. Age i n weeks 1 - 2 97.3 36.2 (61) (69) 3 - 4 19.4 11.9 (67) (218) 5 - 6 12 . 0 1.9 (92) ( 1 5 5 ) c) Behavior i n the test arena Three phases were recognized i n the response of males to the test arena: "exploratory", "courting" and "inter-action". The f i r s t was behavior of the cock while seeking out the source of the hen c a l l s being broadcast. The second was behavior displayed when the dummy female was seen and before there was any reaction to the mirror image. The t h i r d was the reaction to the image (Appendix 12), The exploratory phase was quantified by determining the speed- of advance of the male toward the arena, and by noting the alterations i n his song (Table 18). V i r t u a l l y a l l males, regardless of population, i n -creased the loudness of hooting when the whinny was played. Also, there was a general increase i n the number of complete songs per minute. There was no significant difference between M.Q.L. and C.B. i n tbe rate of approach of the re-sponding males; however, at C.C. the rate of advance was sig n i f i c a n t l y slower than at the other areas. Table 18. Alterations i n song and rate of advance of males during response to test arena. per cent increasing intensity of song mean increase i n f u l l songs per minute advance (feet/ minute) M.Q.L. 100 (n : 2 5 ) 3.41 (n : 2 5 ) 5:21.73 s:4.38 (n:16) C.B. 85 (n:8) 0.85 (n:8) 5:48.79 s:8.3 (n : 7 ) C.C. 93 (n : 2 3 ) 2 . 2 7 (n : 2 5 ) 5:5.00 s:4.03 (n:14) Courtin g was analyzed according to the number of ele-ments o f b e h a v i o r observed p e r minute. Ten p a t t e r n s and poses were recognized. A l l but two of these, "standing" and "gentle pecking" have been described by others. The two new patterns are described i n Appendix 7. In addition, the "hard peck", normally a highly aggressive pattern, was seen. This and other apparently aberrant forms of behavior, such as "normal pose" (upon the back of the hen), accounted for the only differences between areas. When a l l courting acts per -50-minute v/ere t o t a l l e d , the males at M.Q.L. averaged 5«8, C.B. 4 . 1 and C.C. 2 . 3 (Table 1 9 ) . There v/as no difference between M.Q.L. and C.B. or between C.B. and C.C. M.Q.L. did, however, average s i g n i f i c a n t l y higher than C.C. When the "aberrant" forms of behavior are eliminated, there are no significant differences between any of the populations. Therefore there was no difference i n the vigor of courting between the areas, but at M.Q.L. "aberrant" forms of be-havior were more often observed during courting. Table 19. Number minute of acts of courting i n test arena. observed per Study area M.Q.L. C.B. C.C. n: ( 7 ) ( 5 ) (6) mean of a l l acts 5 . 7 6 s :2.6 4 . 1 2 s:0.9 2 . 2 7 s:1.8 mean of a l l acts minus aberrant 3.80 4.06 2 . 2 5 acts The phase of interaction commenced when ,the male re-acted to his mirror image. His response was quantified by measuring the time that elapsed from the moment of his ar-r i v a l u n t i l one of three common aggressive acts were observed (Table 2 0 ) . Also the t o t a l number of aggressive acts observed per minute was calculated from the moment of f i r s t i n t e r -action (Pig. 1 1 ) . - 5 1 -Figure 1 1 . Response of males to test arena by average number of aggressive acts per minute. - 5 2 -Table 20. Time i n minutes, to f i r s t aggressive behavior i n test arena. Study area M.Q.L. C.B. C.C. n: (8) ( 5 ) (8) minutes u n t i l f i r s t aggressive act: "bead-dip" 0.54 4.28 0 . 9 (0.5-0.8) (0.4-12.5) (0.5-1.4) "gu-gu c a l l " 1.80 15.80 4.14 (0.5-5.4) (4.5-20.8) (1.4-6.4) "wing s t r i k e " 2.58 8 . 77 3 . 7 3 (0.8-5.4) (4.8-14.7) (0.5-9.4) No difference emerged between the areas i n the time taken for a response to the mirrors. In addition, no d i f f e r -ences were evident i n the types of behavior patterns, ob-served i n front of the mirrors. However, when the average number of aggressive acts performed per minute, was determined and a mean was calculated for each population, the differences shown i n Fig. 11 were evident. Again the mean for M.Q.L. was s i g n i f i c a n t l y higher than that for C.C., but there was no significant difference between M.Q.L. and C.B., or be-tween C.B. and C.C. Therefore, responding to the test arena, cocks at M.Q.L. when compared to those at C.C, advanced more quickly toward the "whinny" c a l l , courted the dummy hen with more aberrant aggressive acts, and made a more vigorous attack on the mirror. Cocks at C.B. reacted with intermediate vigor. Summary of behavior results "Spontaneous" t e r r i t o r i a l song was carried on longer into the summer at C.C. than at either M.Q.L. or C.B. Pig. 12-A summarizes some of the important responses of birds tov/ard human observers. Evidently, birds at M.Q.L. (the declining population) and C.B. (the stable population) reacted somewhat s i m i l a r i l y , while birds at C.C. (the re-cently increased population) reacted i n a noticeably d i f f e r -ent manner. Grouse were less frequently observed on the ground and were less often captured at C.C. than at C.B. or M.Q.L. Cocks at C.C. less frequently "hooted" at the ob-server or gave "feather spread" i n response to him. Grouse at C.C. less often gave the " f l u t t e r f l i g h t " when disturbed, less often uttered the "threatening" c a l l s and showed less "attack intention" behavior patterns than grouse at the other areas. The predator avoidance behavior also showed d i f f e r -ences. "Flushing distance" was longer at C.C, time to flush shorter, and distance moved on the ground shorter than at M.Q.L. or C.B. Brood hens defended their young less v i g -orously at C.C Chicks were usually found further from their hen at C.C than at M.Q.L. Chicks at C C showed a greater tendency to f l y immediately when disturbed than chicks at -54-M.Q.L. They also "hid" more frequently at M.Q.L. than at C.C. Chick behavior was not measured at C.B. -55-P i g u r e 12. Summary of behavior r e s u l t s . A comparison of behavior by p o p u l a t i o n . A'- C E N S U S B E H A V I O R Successful capture attempts Flush distanc B= T E S T A R E N A B E H A V I O R Song Attack minor MQL CB CC decreasing stable increasing - 5 6 -DISCUSSION Probably the most sound conclusion drawn from the results of thi s study i s that the f i r s t part of the n u l l hypothesis i s not always true. Twenty various measures of behavior v/ere compared between populations, and i n the majority (16), significant differences v/ere recognized. This held for certain aspects of spontaneous behavior, for the reaction of grouse toward people, and for the response of male grouse toward their mirror images. Moreover, the same differences could be recognized both years of the study by a variety of observers. The behavior was peculiar to area, and not to the year i n which i t was recorded, or to the observer who recorded i t . Blue grouse, observed at the pop-ulation l e v e l , cannot be considered as standard e n t i t i e s . In at least this one major aspect, birds can be noticeably different i n different areas. Without further contrary e v i -dence i t must be concluded that those hypotheses that l i n k changes i n behavior to changes i n numbers i n populations, at least have the potential of being accurate. Variation i n be-havior at the population le v e l i s a prime prerequisite of such ideas. Further, other models which suppose different populations of the same species to be made up of animals which are essentially alike should be examined.critically. It i s suggested that direct regulation of animal numbers - 5 7 -solely through mortality by environmental variables are such hypotheses. Models of regulation of numbers solely through competition for some commodity (Nicholson, 1933; Lack, 1954) or through mortality by such environmental hazards as weather and disease, must be changed ad hoc, to cover the p o s s i b i l i t y of variations i n behavior between d i f -ferent populations. Otherwise, i t i s d i f f i c u l t to see how they can f u l l y explain the numbers of blue grouse. It has been pointed out several times how variants i n natural populations can affect population density (Chitty, 1967; Pimentel, 1963; Wynne-Edwards, 1966). Future study should focus on more specific testing of the various hypo-t h e t i c a l ways behavior can affect population dynamics. The second part of the n u l l hypothesis serves to examine one prediction of such a model. I t i s obviously more complex than the f i r s t part. Chitty (1967) sees population changes as a direct result of. selection for different genetic 'types' i n a population. One evidence of this selection i s a change i n the aggressiveness of individuals as populations r i s e or f a l l . He predicts that "animals present i n stationary or declining populations have been selected for their superior a b i l i t y to survive the effects of mutual interference." He la t e r states that th i s means "supposedly more aggressive individuals i n the stationary or declining populations". This contains two major statements that must be examined. The f i r s t concerns numerical differences between the popul-ations, and the second concerns the basis of the differences 'jo-i n behavior between areas. Population trends and dynamics The densities of a l l three populations i n this study had different trends. These trends were established from long term study prior to, and including this study. At the 'increasing' population, the trend prior to th i s study was determined from rel a t i v e success of hunters i n f a l l , and not from counts of breeding birds as was the case at the other two areas. In these l a t t e r two, I was able to confirm the trends as declining and n i l (stable), through counts. However, at the 'increasing' population, the same method did not confirm an increase over the two years of the work. Hunter returns can be a very crude estimate of grouse popul-ation density at times, because hunter success also depends on unrelated factors such as annual production and the time of migration. It i s unlikely however, that production would continue to r i s e and migration time continue to retard from 1964-67. There was a continual, and very large increase i n the success of hunters i n this period. Therefore i t seems safe to conclude that the population had increased and i n 1968 became stable. Since the breeding adults of the area were dying at approximately 30$ annually, most of the birds associated with this r i s e would s t i l l be i n the population i n 1968. For this reason, the population was considered to be of the 'increasing' type for the purpose of.this study. An important feature of the results i s that I was not able to show obvious differences .in other population para-meters, which correlated with the observed trends and dens-i t i e s . The mortality of adults appeared similar i n a l l areas and did not d i f f e r s i g n i f i c a n t l y from that reported i n the past from stable populations. Also, recruitment i n any one year, was similar between areas and was not s i g n i f -icantly different from stable populations i n other studies. These conclusions are boviously inconsistent with the con-clusions above that the trends of the populations were-dif-ferent. The mortality data may have been affected by method. In fact, no.annual mortality rate could be calculated for the 'increasing' area. This resulted because no birds could be captured and banded there (Table 9 ) . I suggested that mortality of adults could be estimated from age structure figures, assuming my measurement of a stable population from 1 9 6 7 - 6 8 was accurate.- This indicated mortality about the same as at the other areas. However, thi s may have i n t r o -duced an error. Mortality of adults i n 1 9 6 7 - 6 8 may have been extreme. This may have prevented an increase i n density. There i s no way to check t h i s p o s s i b i l i t y , however either way thi s cannot affect the v a l i d i t y of the test which depends primarily on trend. S i m i l a r i l y , recruitment may, i n fact, have been d i f -ferent between areas. In this case, my conclusion i s based on the same kind of data for each area - a captured and/or shot sample of birds. A l l were of the same relative accuracy. -60-T n t e r e s t i n g l y , when the two y e a r s ' data were pooled, M.Q.L. (the d e c r e a s i n g p o p u l a t i o n ) showed a s i g n i f i c a n t l y lower r e c r u i t m e n t than the other two a r e a s . Conclusions from these data are weak, but suggest t h a t r e c r u i t m e n t may, i n f a c t , have been h i g h e r i n the expanding and s t a b l e p o p u l a t i o n s than i n the d e c l i n i n g . T h i s would e x p l a i n the apparent f a l l of t h a t p o p u l a t i o n . P r o d u c t i o n of c h i c k s was the one parameter which d i d prove d i f f e r e n t between a r e a s . The d i f f e r e n c e c e n t e r e d around s u r v i v a l from the nest t o the time of m i g r a t i o n , a l -though i n one year ( 1 9 6 7 ) i t a l s o i n c l u d e d a d i f f e r e n c e i n the numbers of nonproductive hens. I n a l l cases, the d i f f e r -ences favoured the i n c r e a s i n g area over the other two. Popu-l a t i o n s of r e d grouse (Watson, 1 9 6 5 ) , w i l l o w ptarmigan (Mercer, 1 9 6 9 ; Bergerud, 1 9 7 0 ) , and r o c k ptarmigan (Theberge, 1 9 7 0 ) have a l s o shown v a r y i n g p r o d u c t i v i t y , which c o r r e l a t e d w i t h the dynamics of the p o p u l a t i o n . At l e a s t i n the case of the w i l l o w ptarmigan, r o c k ptarmigan and blue grouse i n t h i s study, i n c r e a s e d p r o d u c t i v i t y was a s s o c i a t e d w i t h an i n c r e a s -i n g p o p u l a t i o n . The e f f e c t of t h i s d i f f e r e n c e on the p o p u l a t i o n s , i s q u e s t i o n a b l e . Obviously, expanding p o p u l a t i o n s must have more r e c r u i t s than deaths, and t h e r e f o r e must have r e l a t i v e l y more r e c r u i t s than s t a b l e or d e c l i n i n g p o p u l a t i o n s . In ex-panding p o p u l a t i o n s of blue grouse, i n c r e a s e d numbers of p o t e n t i a l r e c r u i t s ( c h i c k s ) may somehow r e s u l t i n i n c r e a s e d numbers g e t t i n g i n t o the breeding p o p u l a t i o n . This i s not -61-the case f o r s t a b l e p o p u l a t i o n s -. i n years when p r o d u c t i o n i s h i g h , t h e r e i s s i m p l y an i n c r e a s e i n the w i n t e r l o s s ( B e n d e l l , 1955 and unpublished r e s u l t s ; Z w i c k e l , 1 9 6 5 ) . Nor d i d the number of young produced, determine whether p o p u l a t i o n s of w i l l o w ptarmigan would i n c r e a s e or decrease -even though p r o d u c t i v i t y d i d i n c r e a s e w i t h the p o p u l a t i o n d e n s i t y (Mercer, 1 9 6 9 ) . Indeed, the c o n c l u s i o n t h a t an ex-cess of young i s produced by n a t u r a l p o p u l a t i o n s i n a l l y e a r s , has been r e l a t i v e l y g e n e r a l (Lack, 1966; J e n k i n s , 1963; Choate, 1963; Boag, 1964, 1965). The answers t o many of the above quandries may be r e s o l v e d , as f i e l d technique i n the case of the blue grouse, becomes more r e f i n e d . P o p u l a t i o n changes seem to take p l a c e r e l a t i v e l y s l o w l y i n these b i r d s . Por example, Boag (1965) d e s c r i b e s a 10$ annual d e c l i n e and i n t h i s study M.Q.L. was d e c l i n i n g at a s i m i l a r 10$ w h i l e C.C. a p p a r e n t l y rose at 12$ a n n u a l l y . The present f i e l d methods seem to be p e r f e c t l y adequate to measure these o v e r a l l changes i n abundance. I t i s p o s s i b l e , however, t h a t they are not s e n s i t i v e enough t o measure the s l i g h t changes i n other parameters such as age s t r u c t u r e , m o r t a l i t y and p r o d u c t i v i t y which are r e l a t e d t o the changes i n abundance. Three d i f f e r e n t d e n s i t i e s were r e -corded, one r e l a t i v e l y h i g h , one medium and one low. At l e a s t two t r e n d s e x i s t e d , d e c l i n i n g and s t a b l e . On weaker evidence, an i n c r e a s i n g d e n s i t y v/as r e c o g n i z e d . -62-The case for differences i n aggression between,  populations The next stage i n applying the results of this study to the n u l l hypothesis, involves examining the behavior d i f -ferences, to see i f there i s any merit i n concluding aggress-ive differences between populations. The behavior which was recorded can be divided into three categories, according to the certainty of i t s interpretation as agonistic behavior. In the f i r s t category i s a l l behavior which i s known to occur i n interactions between grouse. This behavior has been des-cribed largely from an aviary, but i n most cases, qualifying observations have been made i n the f i e l d . A l l this behavior i s well documented as agonistic behavior, either aggressive, non-aggressive or some intermediate. The second category i s behavior which i n t u i t i v e l y , when compared to the behavior of other animals, can be interpreted as agonistic behavior. Generally, no specific data i s known, however, to support t h i s interpretation. The t h i r d category contains a l l the re-maining behavior which i s probably not agonistic behavior. The f i r s t category of behavior i s the most important to apply to the n u l l hypothesis. It includes behavior of attack intention such as the "gu-gu threat c a l l " , "neck stretch" and "head dip" as v/ell as "hard peck","wing s t r i k e " and other gestures of fighting. In every case, regardless of the situation i n which th i s behavior was recorded, birds at the increasing population less frequently used the pat-terns than birds at the stable and declining populations. This i s d i r e c t l y contrary to what the n u l l hypothesis pre-dicted. The f i r s t group of behavior elements also includes the one display which can be interpreted as appeasement or submissive behavior - the "crouch and run". This pattern, adopted by subordinate yearling males i n the presence of singing males, seems to reduce threatening display and appar-ently acknowledges higher social rank (Appendix 8). In con-trast to what the n u l l hypothesis predicted, this pattern was seen most frequently i n the increasing populations-. In discussing the second category of agonistic be-havior, the term threat i s used to refer to those gestures which communicate higher social status, and not only direct intentions of attack. The second category contains, as a major component, behavior of t e r r i t o r i a l ownership such as the "hoot song", " f l u t t e r f l i g h t " and the "feather spread display". I t now appears that most of the male actions and ornamentation that were once thought to be direct lures to the female can be interpreted as threats to other males -females are attracted to these, secondarily. (Guthrie, 1 9 7 0 ) . Hjorth ( 1 9 6 7 ) examined this general theme i n the family Tedraonidae and found i t applicable: "Apparently, all.phases of male reproductive behavior...are threats of varying i n -tensity. The majority of grouse males seem sex-unconscious u n t i l very late before the consummatory act." (p. 2 4 1 ) Therefore by this interpretation, i f an intruder i s greeted v/ith any or a l l of the above behavior, the behavior displayed, and the bird displaying i t , can be termed threatening and -5'+-aggressive. In v i r t u a l l y every case, regardless of the situation i n which the behavior was recorded, birds at the increasing population used these 'threatening* patterns less frequently than birds at the stable and declining populations. The only case where thi s conclusion apparently did not hold, was also the only spontaneous behavior I was able to measure. The number of males participating i n broadcast singing was higher i n the increasing population. Birds were heard, hoot-ing at the increasing area (C.C.) i n August, while at the other areas none at a l l were heard. Singing was probably more widespread even i n June and July at C.C. These results are i n agreement with Bendell & E l l i o t t (196?) who state that grouse hoot more i n dense populations at a l l times. The dens-i t y of grouse at C.C. was much higher than at either of the other areas (Fig. 3). However, there i s no reason to suspect the explanation of these authors, that this occurs simply because grouse stimulate each other more i n dense populations, and not because the birds themselves are different. There i s a large difference between spontaneous, broadcast song and the rest of the behavior mentioned i n this study which was e l i c i t e d by a v i s i b l e intruder to which the, grouse was forced to react. In spite of t h i s , i f t e r r i t o r i a l song i s indeed a threat, th i s result must remain as the one piece of ev-idence which did align with the n u l l hypothesis and against the general model being tested. The "chick-defense" behavior of hens may also contain -65-aggressive elements. I t shows as i t s main feature, a type of advertising display somewhat similar to the male's "feather spread display" and also shows other more d i r e c t l y aggressive elements such- as "hard pecking" and "wing s t r i k -ing". There are no data, however, which show that hens which defend their chicks aggressively, are also aggressive i n encounters with other grouse. The behavior does not seem to be related to increased production of chicks because i n this study, the area that showed the most vigorous chick defense also showed the poorest production. Jenkins et a l (1967) show a variation i n brood defense behavior which seemed to be related to changes i n population size i n red grouse. In the present study, brood defense was far more conspicuous i n the declining and stable populations, and this may relate to the n u l l hypothesis i n some indirect way. The t h i r d category of behavior i s important because the general model proposes a single, unifying factor (agon-i s t i c behavior) to explain the findings. The various types of chick behavior, the measures of how "approachable" grouse v/ere, the response of male grouse to the "whinny" c a l l , and the response of males to the dummy female are involved. Some of these measures showed s t r i k i n g differences between areas. Yet, no case for their interpretation as agonistic behavior seems possible. This means that although the birds showed differences i n their agonistic behavior which did align against the n u l l hypothesis, they also showed differences i n other behavior which may not be related to agonistic -66-behavior at a l l . The general theory being tested did not include these other types of behavior. This leaves the a l -ternate p o s s i b i l i t y open. Population dynamics may relate more di r e c t l y to some other type of behavior than agonistic behavior. The model may have to be changed to cover th i s p o s s i b i l i t y . A case could be made, that any interpretation of the results could be questioned on the basis that they v/ere simply an a r t i f a c t . I gathered most observations from s i t -uations quite removed from an actual "grouse - grouse" en-counter. There i s no way to show that behavior grouse use toward humans i s related to the behavior they show toward other grouse. Moreover, even the control situation - the test arena, suffers i n the same way. The situation was "un-real" i n several ways including the dubious function of the "whinny" c a l l , the exactly opposing movements- of the mirror, the corners of the mirror where no image could be seen, and possibly others. This argument can be levelled quite widely at those who have presented animals with test situations. Pish have been presented with a variety of models to test which colors and shapes e l i c i t attach (Lismann, 1932). McBride (1958) tests chicks and predicts which would be dominant i n the actual encounter betv/een birds. These, and most who use models, mirrors, and "complete stimulus situations" (Tin-bergen, 1951, 1959; Noble, 1935; Marler, 1955; and others) imply that the conclusions they draw w i l l hold true i n the -67-related "re a l " situations. Theberge (1971) reviews the use of mirrors as an ethological tool and concludes that i t i s a r e l i a b l e method for studying animals i n int r a - s p e c i f i c encounters. Obviously these test situations w i l l never be exactly similar to the rea l situations. However, there i s increasing evidence that they can be used to accurately predict what w i l l happen i n r e a l situations. One feature which makes a r t i f a c t unlikely i s the variety of different observations which led to the same con-clusion. I t was possible to quantify 20 different measures of behavior from three widely different situations. In 16 of these measures, significant differences were recognized. A l l of these contrasted the increasing population with the other two. The six or seven which could be interpreted as agonistic differences, likewise contrasted the increasing stock with the others. The results are also open to empirical testing by repetition. As the science of ethology develops, i t may be possible to interpret the reaction of animals to different situations, 'with more certainty. This type of study should be repeated with various populations i n a variety of d i f -ferent (and similar) stages of growth. Different methods of measuring behavior should y i e l d similar r e s u l t s . Note that this study did not address i t s e l f to the problem of determining the source of the behavior d i f f e r -ences between populations. Christian et a l ( 1 9 6 4 ) contends that phenotypic changes i n behavior cause population changes. -68-Chitty (1967) feels genetic changes i n behavior have the same effect. Both p o s s i b i l i t i e s are obviously open i n the present study. ' At least one behavioral difference (the amount of t e r r i t o r i a l song) was explained previously as a phenotypic effect of density (Bendell & E l l i o t t , 1967). The answer to this question w i l l await the appropriate re-search. The effect of the behavioral differences on popul-ation performance i s open to further comment. Aggression and population regulation A number of authors report changes i n behavior which relate to changes i n density (Kluyver et a l , 1 953 ; King, 1955; Jenkins, 1961; Watson, 1965; Tompa, 1964; Sadlier, 1965; Healey, 1965). However, a l l of these consisted only of brief seasonal changes i n behavior. The changes, for example the onset of t e r r i t o r i a l behavior, were followed by an elimin-ation of some portion from the potential breeders. These authors suggest that this elimination was determined i n i n -tensity by the behavior of the animals. But their data can-not be used to support t h i s . Their results are extremely im-portant though, because they show ways i n which behavior can d i r e c t l y affect survival and population size. Another kind of evidence i s a demonstration, that the intensity of an elimination from the population, varies d i r -ectly with the amount or severeness of social interaction. Errington (1951) shows that fighting was greater i n years of declining muskrat (Ondatra zibethica) numbers. Mercer (1969) -69-f e e l s t h a t w i l l o w p t a r m i g a n were more a g g r e s s i v e as t h e i r p o p u l a t i o n d e c l i n e d . Watson (1964) shows t h a t as r e d grouse p o p u l a t i o n s became more s p a r s e , b i r d s defended l a r g e r t e r r i -t o r i e s and were more a g g r e s s i v e . Theberge (1971) c o n c l u d e s t h a t c h i c k s t a k e n from a r o c k ptarmigan p o p u l a t i o n and t e s t e d i n the l a b , showed h i g h e r a g g r e s s i v e n e s s i f t a k e n from a p o p u l a t i o n which had peaked and s t a r t e d a d e c l i n e , t h a n i f t a k e n from an i n c r e a s i n g one. These s t u d i e s have shown t h a t the s e v e r e n e s s o f s o c i a l i n t e r a c t i o n can change as the d e n s i t y o f a p o p u l a t i o n changes. They do not show how t h i s c hanging b e h a v i o r a f f e c t s the e l i m i n a t i o n of i n d i v -i d u a l s from the b r e e d i n g s t o c k . O b v i o u s l y the above r e p r e s e n t the r e s u l t s of two d i f -f e r e n t t y p e s of s t u d y . Both k i n d s must be c a r r i e d out w i t h the same p o p u l a t i o n i f t h e r e i s t o be a t r u e e v a l u a t i o n of b e h a v i o r i n r e g u l a t i n g i t s numbe'rs. The f i r s t type of study attempts t o answer the q u e s t i o n : I s a s u r p l u s group o f a n i m a l s produced s o l e l y by i t s f a i l u r e t o be supreme d u r i n g some b e h a v i o r a l p r o c e s s ? The second type of study a s k s : I s the s e v e r i t y o f the ( h y p o t h e t i c a l ) c o n t e s t f o r supremacy (and t h e r e f o r e the number e l i m i n a t e d ) a f u n c t i o n of v a r i a t i o n i n the b e h a v i o r of the a n i m a l s themselves? T h i s work has made a s m a l l c o n t r i b u t i o n towards answering the l a s t q u e s t i o n i n the case of b l u e g r o u s e . A f i r s t s t e p i n d e t e r m i n i n g whether some b e h a v i o r a l c o n t e s t can be e f f e c t e d by v a r i a t i o n s i n the b e h a v i o r between i n d i v i d u a l grouse, v/as t o show t h a t the same k i n d of b e h a v i o r can be -70-noticeably different between birds- More s p e c i f i c a l l y , the results suggested that differences i n agonistic behavior existed between grouse, and this could be seen most s t r i k -ingly when birds of different populations were compared. Moreover, i t i s further suggested that s t r i k i n g differences i n agonistic behavior v / i l l most often be found between popu-lations of different trend. The findings apparently support the idea that social interactions may be more severe i n some populations, notably those that are declining or stable as compared to those that are increasing. They cannot, however, be used to suggest that the differences i n behavior v/ere causing the densities to change. This i s largely because the f i r s t study, mentioned above, has never been carried out on blue grouse. The period during f a l l , winter or early spring when the grouse have not been studied (Bendell & E l l i o t t , 1967; Lance, 1967) may be the time when adjustment occurs. U n t i l a detailed study of the ethology and numbers of grouse during t h i s part of their l i f e history can be carried out, any further speculation on the relationship between behavior and the regulation of numbers i n these birds i s unwarranted. It i s possible that behavior and population are re-lated i n a cause and effect relationship by some type of social struggle, perhaps occurring on the v/inter habitat. At this time, the model being tested contends that less aggress-ive birds are excluded from the population. However, i n populations where habitat i s freely available, the 'contest' -71-i s very mild and most birds are able to survive. The •contest' has a two part purpose then: i t e.jects some potential recruits from the population and i t acts as a s e l -ective force favouring aggressiveness. Presumably i n an increasing population, as the habitat a v a i l i b i l i t y decreases, the elimination (and therefore the selective force) becomes more severe u n t i l the population s t a b i l i z e s . My results do not appear to f i t this viev; on two points. F i r s t l y , i f s e l -ection affects agonistic behavior, i t apparently affects other types of behavior as w e l l . It i s possible that these other types of behavior are included i n the things s e l -ected for i n the absence of selection for aggression ( i e . : " . . . . f i t t e d , to v/ithstand a l l other hazards of their environ-ment", Chitty (1967) p. 64). But t h i s needs testing. Second-l y , the population at C.C. apparently ceased to increase i n 1968, however i t s behavior was not noticeably different from 1967 and continued to- contrast with C.B., another stable population. I t i s possible that changes i n behavior i n blue grouse are too slig h t to detect for several years following an increase because of their r e l a t i v e l y slow turnover. The relationship between population dynamics and agression i s probably not as simple as predicted by the general model. There are some clues to the type of social struggle that may occur. As mentioned, regulation of numbers i n blue grouse i s correlated with the disappearance of chicks i n their f i r s t winter (Bendell & E l l i o t t , 1967), A 'regulated' number of chicks are successful i n the social contest so - 7 2 -t h a t , each y e a r o n l y the amount r e q u i r e d t o r e p l a c e m o r t a l -i t y and c o n t i n u e the t r e n d o f the p o p u l a t i o n s u r v i v e . The w i n t e r h a b i t a t i s v e r y d i f f e r e n t and f a r removed from the summer h a b i t a t . Yet i t i s on the summer h a b i t a t t h a t the evi d e n c e o f r e g u l a t i o n has been ob s e r v e d . A l s o grouse appar-e n t l y a d j u s t t h e i r numbers t o l o c a l c o n d i t i o n s on the summer range ( E l l i o t t , 1 9 6 5 ) . I t i s u n l i k e l y t h a t a s o c i a l c o n t e s t on the w i n t e r range c o u l d have the s e e f f e c t s . I t i s s i m p l e r t o assume, t h a t , as i n the r e d grouse ( J e n k i n s e_t a l , 1 9 6 5 ) the s o c i a l i n t e r a c t i o n t a k e s p l a c e on the b r e e d i n g grounds. The b r e e d i n g grounds have r e c e i v e d the l e a s t study i n the l a t e w i n t e r when grouse f i r s t r e t u r n t o i n h a b i t them. B e h a v i o r , n o t a b l y a g g r e s s i v e b e h a v i o r , has the po-t e n t i a l f o r v a r y i n g between p o p u l a t i o n s i n r e l a t i o n t o t h e i r p o p u l a t i o n t r e n d s . B e h a v i o r t h e r e f o r e has the p o t e n t i a l f o r a c t i n g as a c a u s a l f a c t o r on p o p u l a t i o n performance. T h i s p o t e n t i a l can b e s t be examined by examining p o p u l a t i o n s f o r e v i d e n c e o f s o c i a l s t r u g g l e ' and o f an o u t c a s t group. - 7 3 -SUMMARY T h i s s t u d y was t o t e s t t h e h y p o t h e s i s t h a t b e h a v i o r r e g u l a t e s t h e d e n s i t y o f b l u e g r o u s e . I t examined t h e p r e -d i c t i o n s t h a t g r o u s e f r o m d i f f e r e n t a r e a s can behave d i f -f e r e n t l y so t h a t r e l a t i v e l y n o n - a g g r e s s i v e b i r d s a r e f o u n d i n a r e a s w i t h i n c r e a s i n g numbers as compared t o b i r d s f r o m a r e a s w i t h s t a b l e o r d e c l i n i n g p o p u l a t i o n s . Grouse d e n s i t i e s d u r i n g t h e s t u d y d i d n o t change on two a r e a s b u t d e c l i n e d on a t h i r d . One s t a b l e p o p u l a t i o n had r e c e n t l y r i s e n t o an e x t r e m e l y h i g h d e n s i t y , and was t r e a t e d as an ' i n c r e a s i n g ' t y p e o f p o p u l a t i o n f o r t h e p u r p o s e o f t h e s t u d y . The o t h e r two were o f a v e r a g e t o low d e n s i t y . The e n v i r o n m e n t s o f t h e t h r e e p o p u l a t i o n s had t h e same c l i m -a t e , and v e g e t a t i v e c o v e r . The a n n u a l m o r t a l i t y o f a d u l t s was s i m i l a r i n a l l t h r e e a r e a s ( a p p r o x i m a t e l y 3 0 $ ) . The r e c r u i t m e n t i n any one y e a r was not m e a s u r a b l y d i f f e r e n t between a r e a s ; however, t h e d e c l i n i n g a r e a showed a l o w e r r e c r u i t m e n t o v e r t h e two y e a r s o f t h e s t u d y . P r o d u c t i o n was h i g h e s t i n t h e ' i n c r e a s -i n g ' p o p u l a t i o n , b u t a l l a r e a s p r o d u c e d ample c h i c k s t o r e -p l a c e a n n u a l m o r t a l i t y o f a d u l t s . Three t y p e s o f b e h a v i o r were r e c o r d e d : s p o n t a n e o u s s o n g , t h e r e a c t i o n o f g r o u s e t o humans, and t h e r e a c t i o n o f c o c k s t o a t e s t o f a g g r e s s i o n w h i c h i n c l u d e d m i r r o r s . Of 2 0 v a r i o u s measures o f b e h a v i o r , 16 r e v e a l e d s i g n i f i c a n t d i f f e r --74-ences between the populations. The majority of these were between the 'increasing' population and the other two. Aggressive patterns (threatening c a l l s , "head dips", "neck stretches") were seen more frequently than non-aggress-ive patterns ("crouch and run") at the declining and stable areas, compared to the area that had been increasing. Other behavior for which aggressive interpretation i s only i n t u i t i v e ("feather spread display", song) also indicated that the increasing type of grouse were less aggressive. Much of the behavior recorded was not agonistic behavior, and here differences also occurred. Therefore, although aggressive differences were noted, other differences i n behavior also occurred between the populations. The hypothesis adequately predicted the findings of the study. Behavior, notably agonistic behavior, has the potential for varying between stocks. Hostile in t e r -actions between grouse has, at least the potential for caus-ing the variable disappearance of chicks which results i n the regulation of blue grouse populations. However, the study did not answer the problem of determining the cause of the behavior differences, nor of determining whether the behavior differences were, i n fact, causing the population dynamics to be different i n the various areas. Many studies have shown that behavior i s i n some way related to popu-la t i o n processes; very few have shown how the effect i s mediated to the actual numbers of the animals. In blue -75-grouse, the adjustment l i k e l y o c c u r s during' the w i n t e r or on the b r e e d i n g h a b i t a t i n l a t e w i n t e r and e a r l y s p r i n g . -76-LITERATURE CITED Bendell, J . F., 1954. A study of the l i f e h i s t o r y and pop-u l a t i o n dynamics of the sooty grouse, Dendragapus  obscurus f u l i g i n o s u s (Ridgway). Unpubl. Ph.D. t h e s i s , U n i v e r s i t y of B.C. , 1955a. Age, breeding behavior and migration of sooty grouse, Dendragapus obscurus f u l i g i n o s u s (Ridgway). Trans. N. Am. W i l d l . Conf„, 20:367-381. , 1955b. Disease as a c o n t r o l of a population of blue grouse, Dendragapus obscurus f u l i g i n o s u s (Ridgway). Can. J . Zool., 33:195-223. , and P.W. E l l i o t t , 1966. Habitat s e l e c t i o n i n blue grouse. Condor, 68:451-446. _______ and , 1967. Behavior and the r e g u l a t i o n of numbers i n blue grouse. Can. W i l d l . Serv. Report Ser. No. 4, 76 pp. Bergerud, A. T., 1970. Population dynamics of the willow ptarmigan,,Lagopus lagopus a l l e n e i i n Newfoundland, 1955-1965. Oikos, 21:299-325. Blackford, J.L., 1963. Further observations on the breed-ing behavior of a blue grouse population i n Montana. Condor, 65:485-513. Boag, D.A., 1964. A population study of the blue grouse i n southwestern A l b e r t a . Unpubl. Ph.D..thesis, Wash. State U n i v e r s i t y , 129 pp. , 1965- Indicators of sex, age and breeding phenology i n blue grouse. J . W i l d l . Mgmt., 29:103-108. , 1966. Population a t t r i b u t e s of a blue grouse pop-u l a t i o n i n southwestern A l b e r t a . Can. J . Zool., 44:799-814. Brooks, Ac, 1926. The d i s p l a y of Richardson's grouse with some notes on the species and subspecies of the genus Dendragapus. Auk, 43:281-287. -77-C a r r i c k , R., 1963, E c o l o g i c a l s i g n i f i c a n c e o f t e r r i t o r y i n the A u s t r a l i a n magpie, Gymnorhina t i b i c e n . P r o c . X I I I I n t e r n O r n i t h o l . Congr., pp. 740-753. C a r r i c k , R., and M. D. Murray, 1964. S o c i a l f a c t o r s i n pop-u l a t i o n r e g u l a t i o n o f the s i l v e r g u l l L arus n o v a e h o l -l a n d i a e . Stephens. C.S . I.R.O. W i l d l . Res., 9:189-199. C h r i s t i a n , J . J . , and D.E. D a v i s , 1964. E n d o c r i n e s , b e h a v i o r and p o p u l a t i o n . S c i e n c e , 146:1550-1560. C h i t t y , D., i960. P o p u l a t i o n p r o c e s s e s i n the v o l e and t h e i r r e l e v a n c e t o g e n e r a l t h e o r y . Can. J . Z o o l . , 38:99-113. , 1964. Animal numbers and b e h a v i o r , i n : F i s h and W i l d l i f e . A memorial t o W„ J . K. Harkness. Ed. J.R. Dymond. Honyman, Can. pp. 41-53* _______ and E. Ph i p p s , 1966. S e a s o n a l changes i n s u r v i v a l i n mixed p o p u l a t i o n s o f two s p e c i e s o f v o l e . J . Anim. E c o l . , 35:313-331. , 1967. The n a t u r a l s e l e c t i o n o f s e l f - r e g u l a t o r y b e h a v i o r i n animal p o p u l a t i o n s . P r o c . e c o l . A u s t . , 2:51-78. Choate, T. S., 1963. H a b i t a t and p o p u l a t i o n dynamics o f w h i t e - t a i l e d p t a r m i g a n i n Montana. J . W i l d l . Mgmt., 27:684-699. C r a i g , J . W., L. C. Ortman, and A. M. Guhl, 1965. G e n e t i c s e l e c t i o n f o r s o c i a l dominance a b i l i t y i n c h i c k e n s . Anim. Behav., 13:114-133. D a v i s , D, E., 1964. The p h y s i o l o g i c a l a n a l y s i s o f ag g r e s -s i v e b e h a v i o r , i n : S o c i a l b e h a v i o r and o r g a n i z a t i o n among v e r t e b r a t e s . Ed. W. E t k i n . U n i v . o f Chicago p r e s s , pp. 53-74. E l l i o t t , P. W., 1965. F a c t o r s a f f e c t i n g the l o c a l d i s t r i b u -t i o n o f b l u e grouse on a b r e e d i n g r a n g e . M.Sc. t h e s i s U n i v e r s i t y o f B.C., 92 pp. E r r i n g t o n , P. L., 1 9 5 1 - C o n c e r n i n g f l u c t u a t i o n s i n p o p u l -a t i o n s o f the p r o l i f i c and w i d e l y d i s t r i b u t e d muskrat. Am. N a t u r a l i s t , 85 : 2 7 3 - 2 9 2 . -78-Guthrie, R. D., 1970, Evolution of human threat display organs. Evolutionary Biology, 4:257-302. Healey, M. C., 1967. Aggression and self-regulation of pop-ulation size i n deermice. Ecol., 4-8:377-392. Hjorth, I., 1967. Fortplantninsbetweenden inom honsfag-elfamilsen Tetraonidae. Var.Fegelvarld Arg., 26:193-241. Hornocker, M. C., 1969. Winter t e r r i t o r i a l i t y i n mountain l i o n s . J. Wildl. Mgmt., 33:457-464. Jenkins, D., 1961. Social behavior i n the partridge Perdix  perdix. I b i s , 103a:155-188. , A. Watson, and G„ R. Miller,-1963. Population stud-ies on red grouse, Lagopus lagopus scoticus (Lath.) i n northeast Scotland. J. Animal Ecol., 32:317-376. _, 1963. Population control i n red grouse. Proc. 13th Intern. Ornith. Congr., pp. 690-700. __ , A. Watson, and G. R. M i l l e r , 1967. Population f l u c t -uations i n the red grouse, Lagopus lagopus scoticus. J. Animal Ecol., 36:97-122. King, J. A., 1955. Social behavior,social organization and population dynamics of a black-tailed p r a i r i e dog town i n the Black H i l l s of S. Dakota. Contr. Lab. Vertebr. B i o l . , University of Mich., 67:1-123. King, R. D., 1968. Food habits i n relation to the ecology and population dynamics of blue grouse. Unpubl. M.Sc. thesis, University of B.C. 62 pp. Kluyver, K.N., and L. Tinbergen, 1953. Territory and the population of density i n titmice. Arch. Neerl. Zool., 10:265-289. Krajina, V. J. (editor), 1965. Ecology of western North America, v o l . 1. Dept. of Botany, University of B.C., Vancouver, 112 pp. Krebs, C. J., 1966. Demographic changes i n fluctuating pop-ulations of Microtus californicus . Ecol. Monog., 36:239-273. Lack, D., 1954. The natural regulation of animal numbers. Claredon Press, Oxford. 343 PP» - 7 9 -, 1966. P o p u l a t i o n s t u d i e s o f b i r d s . C l a r e d o n P r e s s , O x f o r d . 341 pp. Lance, A.N.,1967- A t e l e m e t r y study o f d i s p e r s i o n and b r e e d i n g b i o l o g y i n b l u e g r o u s e . Unpubl. M.Sc. t h e s i s , U n i v e r s i t y o f B.C. 44 pp. Lismann, H. W., 1932. Die Umwelt dws k a m p f f i s h e s ( B e t t a splendens Regan), c i t e d from: M a r l e r , P. R. and W.J. Hami l t o n , 1966. Mechanisms of animal b e h a v i o r , W i l e y P r e s s , New York. Lumsden, H, G., 1965. D i s p l a y s o f the s h a r p t a i l g r o u s e . Res. Branch, Ont. Dept. Lands & F o r . Tech. s e r . , Rep. #66. M a r l e r , P., 1955. S t u d i e s o f f i g h t i n g i n c h a f f i n c h e s (2), the e f f e c t o f dominance r e l a t i o n s o f d i s g u i s i n g females as males. B r i t . J . Anim. Behav., 3:137-146. , and W. J . Hamil t o n , 1966. Mechanisms of animal be-h a v i o r . John W i l e y & Son, New York, 771 pp.. McBride, G., 1958. The measurement of a g g r e s s i v e n e s s i n the domestic hen. Anim. Behav., 6:87-91. Mercer, W. E., 1969. E c o l o g y o f an i s l a n d p o p u l a t i o n of Newfoundland w i l l o w p t a r m i g a n . M.Sc. t h e s i s , U n i v e r -s i t y o f W i s c o n s i n . N i c h o l s o n , A. J . , 1933. The bal a n c e o f animal p o p u l a t i o n s . J . o f Animal E c o l . , 2:132-178. Noble, G. K. and V/. Vogt, 1 9 3 5 . An e x p e r i m e n t a l study o f sex r e c o g n i t i o n i n b i r d s . Auk, 52:278-286. P i c o z z i , N., 1968. Grouse bags i n r e l a t i o n t o the management and. geology o f h e a t h e r moors. J . A p p l . E c o l . , 5: 483-488. P i m e n t e l , D., 1963. N a t u r a l p o p u l a t i o n r e g u l a t i o n and i n t e r -s p e c i e s e v o l u t i o n . P r o c . I n t . Cong. Z o o l . , 16: 329-336. S a d l i e r , R. M. S., 1965. The r e l a t i o n s h i p between a g o n i s t i c b e h a v i o r and p o p u l a t i o n changes i n the deermouse, Peromyscus m a n i c u l a t u s . J . Anim. E c o l . , 14:331-352. -80-Siegel, P. B., I960. A method for evaluating aggressiveness i n chickens. Poultry Science, 39:1046-1048. Smith, N„ D. and I. 0. Buss, 1963. Age determination and plumage observations of blue grouse. J. Wildl. Mgmt., 27:566-578. Smith, S. M., 1967. Seasonal changes i n the survival of the black capped chickadee. Condor, 69:344-359. Southwick, C. H., 1955. Regulatory mechanisms of house mouse populations: social behavior affecting l i t t e r s urvival. Ecol., 36:627-634. S t i r l i n g , I. G., 1965. Studies of the holding, behavior and nu t r i t i o n of captive blue grouse. Unpubl. M.Sc. thesis, University of B.C. 125 pp. 1 , and J . F . Bendell, 1966. Census of blue grouse v/ith recorded c a l l s of a female. J. Wildl. Mgmt., 30: 184-187. , and , 1970. The reproductive behavior of blue grouse. Syesis, 3:161-171. Theberge, J., (manuscript) 'Aggression and control of density i n rock ptarmigan'. Unpubl. Ph.D. thesis, University of B.C. Tinbergen, N., 1 9 5 1 . The study of i n s t i n c t . Oxford Univ. Press, London. , 1959. Comparative studies of the behavior of gulls (Laridae): a progress report. Behavior, 15:1-70. Tompa, F. S., 1964. Factors determining the numbers of song sparrows, Melospiza melodia (Wilson) on Mandarte Island, B. C„, Canada. Acta Zool. Fenn., 109:1-73. Watson, A., 1964. Aggression and population regulation i n red grouse. Nature, 202(4931):506-507. , 1965. A population study of.ptarmigan (Lagopus mutus) in Scotland. J. Anim. Ecol., 34:135-172. , 196'7a. Social status and population regulation i n the red grouse (Lagopus lagopus scoticus). i n : The Royal Soc. Pop. St. Group - abstracts of proceedings # 2 , 1967. pp. 22-30. -81-, 1967b. P o p u l a t i o n c o n t r o l by t e r r i t o r i a l b e h a v i o r i n r e d grouse. Nature, 2 1 5 ( 5 1 0 7 ):1274 - 1 2 7 5 . Watts, C. H. S., 1969. The r e g u l a t i o n o f wood, mouse (Aposemus s y l v a t i c u s ) numbers i n Wytham Woods B e r k s h i r e , J . Anim. E c o l . , 58:285-504. Wing, L., 1946. Drumming f l i g h t i n the b l u e grouse and c o u r t s h i p c h a r a c t e r s o f the T e t r a o n i d a e . Condor, 48: . 1 5 4 - 1 5 7 . Wynne-Edwards, V.C., 1962. Animal d i s p e r s i o n i n r e l a t i o n t o s o c i a l b e h a v i o r . Hafner, New York. 653 pp. Wynne-Edwards, V. C , 1966. R e g u l a t i o n of numbers as a homeo s t a t i c p r o c e s s i n v o l v i n g s o c i a l b e h a v i o r . The Roy a l Soc. Pop. S t . Group - a b s t r a c t o f p r o c e e d i n g s #2, 1967. pp. 7-12. Z w i c k e l , P. C. 1965. E a r l y m o r t a l i t y and the numbers o f b l u e g r o u s e . Unpubl. Ph.D. t h e s i s , U n i v e r s i t y o f B.C. 155 PP. , and A. N. Lance, 1966. De t e r m i n i n g the age of young b l u e g r o u s e . J . W i l d l . Mgmt., 50:712-717. , and J . F. Bendell,.1967a. A snare f o r c a p t u r i n g b l u e grouse. J . W i l d l . Mgmt., 51:202-204. , and , 1967b. E a r l y m o r t a l i t y and the r e g u l a -t i o n o f numbers i n b l u e grouse. Can. J . Z o o l . , 45: 815-851. - 8 2 -APPENDICES APPENDIX I . The v e g e t a t i v e cover of the study areas i n 1967-A: Middle Quinsam Lake. B: Comox Burn. C: Copper Canyon. Appendix 1 (cont'd) - 8 3 -- 8 4 -APPENDIX I I . The p o p u l a t i o n d a t a c a r d . Circle: NCB UB B NB NEST SHOT MISC. OBSERVER GEN. LOC BANDS: R |  DATE TIME Ll ADM (H.S.) YRL M (H.S.) ADF JUV UNIDENT REMAINS. BROOD, C L U T C H SIZE JUV AGE 1. 2. 3. 4. 5. 6. 2-AGES SOUND ONLY: hoot whoot flight flutter gu-gu threat qua-quo cry whinney cluck wrng cmn chel DIS & DIR DROPPINGS: C l Cae Ord H.S., FIB, SFT, GR, GRY, CRT. (old.ne-) . DOG: point break flush by in search, other. COVER: gen veg: VO.O.D.VD. veg 100ft: VO.O.D.VD, Assoc LOCATION: ground stu-Tip 'ree hill log flying; ground wet Y/EATHER: WND (It m S t ) TMP (eld m w ht) PPT (It m hvy) " CLD CHICK DATA: Wh! Fl Prim I 2 3 4 5 6 7 8 DIS & DIR: nrst hooting lost bird worker moving bird flew time this bird _ SPECIFIC LOC ; Legend: not checked f o r bands open UB unhanded -D 0 0 0 0 9 0 0 0 dense new banding *V'X) 0 0 0 0 0 0 0 0 v e r y dense r i g h t l e g A S S O C 0 0 0 0 0 a s s o c i a t i o n l e f t l e g Wht ....... weight a d u l t male f o o t l e n g t h H.S h o o t i n g , s i l e n t .primary YRL • o a • e © y e a r l i n g f e a t h e r a d u l t female n r s t ...... n e a r e s t JUV . . . o o . j u v e n i l e l o c a t i o n wrng 'warning' c a l l 'come-in' c a l l c h i c k c a l l d o c k e r c a e c a l o r d ..... o r d i n a r y f i b f i b r o u s s o f t green gray g r i t v e r y open -85-APPENDIX I I I . "Listening transects" for measuring blue grouse densities. The purpose of this method was to give a quick cen-sus of t e r r i t o r i a l males from a larger area than was possible by t o t a l search. Methods were essentially the same as reported by S t i r l i n g & Bendell (1966). Female grouse c a l l s were trans-mitted with a Wightman E l e c t r i c transistorized amplifier, model C.W. - 6 equipped with an 8-inch horn speaker. Calls were played from p l a s t i c records (45 rpm) which were cut from tape recordings made i n the U.B.C. aviary. The "whinny" c a l l of the hen was the only sound broadcasted at every l i s t e n i n g station. The locations of a l l hooting males v/ere recorded on standard 3" x 5" cards. The cards were blank except that the major compass bearings had been printed on each. The logging road I was using as a transect was marked i n at each station and the card v/as then used as a small map on which to mark singing males. For each song heard, i t s estimated dis -tance, and compass bearing were recorded as well as the num-ber of songs being sung per minute and the number of hoot syllables per song. The time, weather and relat i v e song bird a c t i v i t y were also noted. The information from the cards was lat e r transferred to large scale base maps of the various grades. The lengths of the individual transects were as follows: -86-Transect # (log grade c l a s s i f i -cation, MacMillan & Bloedel Co.) B. W. B-6 B-6-B5 length (yards) 3 , 4 3 5 2 , 5 0 5 3 , 1 5 5 1 , 2 3 0 area effectively censused (sq. yards) 669,000 501,000 631,000 246,000 A l l distances from the lis t e n i n g posts to singing males were estimated. A l l songs estimated at over 1 0 0 yards from the road were eliminated, yielding an effective census of a s t r i p 2 0 0 yards wide. Because l i s t e n i n g posts v/ere approximately 1 0 0 yards apart, most songs were recorded from two different bearings. Because logging grades at the C.C. study area were rarely over 2 5 0 yards apart, the entire area was apparently close enough to roads to be censused with th i s method. This may be the only j u s t i f i c a t i o n for using this method. Grouse prefer open, raised areas from which to hoot ( E l l i o t t , 1 9 6 5 ) and i n some grouse habitat, the only place such features are found i s along roads. To check the accuracy obtained, two roads on either side of the area t o t a l l y searched, were used as li s t e n i n g transects, (Table A 3 - 1 ) . Table A3-1. Number of males counted by t o t a l search and the number counted by list e n i n g count, 41 acres, C.C. Total search 14 #new: Listening counts (Total) 13 1 2 3 4 1 0 1 2 10 12 1 0 3 0 0 - 8 7 -APPENDIX IV. A method of aging blue grouse c h i c k s at a d i s t a n c e . The method of Z w i c k e l and Lance (1966) f o r aging young blue grouse works o n l y i f b i r d s are i n the hand. Be-cause i n the w i l d , many c h i c k s cannot be captured, whereas they can u s u a l l y be observed w e l l enough t o estimate r e l a t i v e f e a t h e r development and s i z e , a method was d e r i v e d f o r aging by these means. Young grouse pass through three c o n s e c u t i v e f e a t h e r c o v e r i n g s i n the course of t h e i r f i r s t y e a r . The f i r s t i s f i n e down, which i s y e l l o w w i t h b l a c k c r y p t i c markings; the second i s the j u v e n i l e plumage, which i s l i g h t y e l l o w and w i d e l y marked w i t h c r y p t i c bands; and the t h i r d i s the f i r s t w i n t e r plumage which resembles a d u l t plumage (Taber, 1963). The time of mo u l t i n g of these v a r i o u s plumages bears a good c o r r e l a t i o n t o the age of the c h i c k ( B e n d e l l , 1955; Boag, 1965; Smith and Buss, 1963; Z w i c k e l & Lance, 1966). Methods I examined 40 s k i n s of c h i c k s c o l l e c t e d from the U.B.C. a v i a r y at v a r i o u s stages of growth. Grouping the s k i n s i n t o s i x 10-day age c a t e g o r i e s , d i f f e r e n c e s were noted i n the r e l a t i v e s i z e , coverage by down, development of the j u v e n i l e and y e a r l i n g f e a t h e r s and ge n e r a l appearance, between the groups. Two r e p r e s e n t a t i v e sketches of c h i c k s from each age group were prepared. One showed a c h i c k on the ground and i l l u s t r a t e d f e a t h e r development. The other was a s m a l l e r -88-silhouette of one i n f l i g h t (Fig. A4-1). On occasion, chicks were captured which had been aged previously by the sketches. Results Figure A4-1 i l l u s t r a t e s the sketches used for f i e l d reference and the c r i t e r i a used for assigning chicks to the various groups. In practice, the sketches alone were suf-f i c i e n t for most observers to assign age groups and the verbal c r i t e r i a were rarely used. Table A4-1 shows how the estimated ages of chicks compared with their ages as determined by the method of Zwickel and Lance (1966). Table A4-1. Number of estimates of ages made with chicks of known age, accuracy obtained. Age class: 1 2 3 4 5 6 Total No. of estimates 1 6 4 9 4 5 30 No. accurate 1 4 4 8 1 5 26 % accuracy: 80$ The overall accuracy obtained was 80$ with the poor-est accuracy i n the class 5 group. Class 1 chicks rarely had to be estimated because most of these could be captured. The method served to aid inexperienced f i e l d workers i n \ w -89-estimating approximate ages on sight. For the purpose of this study (a rough s t r a t i f i c a t i o n of behavior observations with chick ages) the method was adequate. Figure A 4 - 1 . - 9 1 -P i g . A4-1 ( c o n t ' d ) . . . -95-APEENDI-X V. A comparison of " b i r d s - p e r - h o u r " census and t o t a l s e a r c h census. The number o f grouse l o c a t e d p e r hour o f 'normal' s e a r c h i n g has been used t o compare r e l a t i v e d e n s i t i e s be-tween ar e a s ( Z w i c k e l , 1965). Because o f b i a s e s i n t r o d u c e d by d i f f e r e n t i a l l o c a t a b i l i t y o f the sexes and s o c i a l groups, the number of lone females l o c a t e d p e r hour i n the p e r i o d p r i o r t o n e s t i n g gave the most a c c u r a t e measure of r e l a t i v e d e n s i t y . T a b l e A5-1 shows the number of lo n e females l o c -a t e d d u r i n g t h i s study at M.Q.L. and C.C. ( p o p u l a t i o n s w i t h l a r g e d i f f e r e n c e s i n a c t u a l d e n s i t y ) . T a b l e A -5-1. Lone hens l o c a t e d p e r hour as a measure of p o p u l a t i o n d e n s i t y . Birds/100 Lone females A l l b i r d s a c r e s , t o t a l p e r hour, p e r hour s e a r c h May 1-June 5 a l l y e a r M.Q.L. 6 1967: 0.4- 1.1 1968: 0.3 0.7 C.C. 34- 1967: 0.6 2.9 1968: 0.7 2.3 There was a d i s c r e p a n c y (by a f a c t o r o f 3) between, the two measures. I t i s e v i d e n t t h a t a l a r g e e r r o r would be i n t r o d u c e d by comparing these two areas by " b i r d s - p e r - h o u r " a l o n e . T h i s d i s c r e p a n c y may be evi d e n c e t h a t s e a r c h time became " s a t u r a t e d " by o b s e r v a t i o n s a t about 2-3 per hour. The average time spent on each o b s e r v a t i o n at M.Q.L. i n 1968 was 11.5 minutes. Adding to this an estimated 5 minutes of "waste" time per observation, a worker used 15-20 minutes per observation. It i s unlikely that he could locate more than 5 birds an hour. At densities similar to those at M.Q.L., birds were located at approximately one per hour. As densities r i s e much over three times this density, the "birds-per-hour" method has limited application. APPENDIX VI. Nesting phenology. I compiled the l i s t s of broods of known age at each population and back-dated these to the dates of hatch. When combined with the hatching dates of the nests located, this yielded hatch peaks for the areas (Pig. A6-1). In a l l populations, 60-80$ of hatches occurred within the same three week period, June 15 - July 5. In 1967, the peak at M.Q.L. and C.B. occurred i n the June 15-21 period while at C.C, i t occurred one week later i n the June 22-28 period. In 1968 M.Q.L. and C.C. peaked together i n the June 22-28 week and CB. peaked the week e a r l i e r . Because these differences are so small i t i s not con-ceivable that they could have been the cause of different survival of chicks and different productivity between areas. Zwickel (1965) reported a mean hatch period i n the week of June 18-24 for M.Q.L. and C.B. i n the 1962-64 seasons which closely matches the results of the present study. - 9 7 -Fi.gu.re A6-1. Number of broods h a t c h i n g d u r i n g g i v e n weeks of the summer, i n per c e n t . 1967 3&I M.Q.L. o 1 0>-Si) C.B. o So Of: 3*) C.C. 1968 o M.Q.L. a (>?-8o) C.B. May (to 3 D June 1-7 8-14 o 15 21 22-28 29- 6-12 J u l y 5 13- 20-19 26 C.C. WEEKS OF BREEDING SEASON (MAY 31 TO JULY 26) / o -98-APPENDIX V I I . B e h a v i o r p a t t e r n s and c a l l s o f b l u e grouse w i t h a g o n i s t i c i n t e r p r e t a t i o n . MALES: P a t t e r n s and poses A g o n i s t i c s i g n i f i c a n c e R e f e r e n c e Normal n e u t r a l pose F l u t t e r f l i g h t F e a t h e r s p r e a d d i s p l a y ( s e x u a l d i s p l a y ) A l e r t pose c r e s t r a i s e d t a i l r a i s e d Neck s t r e t c h ( t h r e a t pose) and p a c i n g Head d i p (head throw) Hoot pose" and d i s p l a y hoot Rush and chase Pace Hard peck ( p e c k i n g ) Wing s t r i k e s i n g l e , d o u b l e . -probably none - i f i n f u l l view may be m i l d l y t h r e a t e n i n g - t e r r i t o r i a l a s s e r t i o n , -moderate t o i n t e n s i v e t h r e a t -sex a d v e r t i s e m e n t , t e r r i t o r y a s s e r t i o n , moderate t o i n t e n s i v e t h r e a t - c o n f l i c t between f l e e -i n g and r e m a i n i n g . -may be m i l d t h r e a t but s i g n i f i c a n c e obscure - i n t e n s i v e , t h r e a t and a t t a c k i n t e n t i o n - i n t e n s i v e t h r e a t and a t t a c k i n t e n t i o n - t e r r i t o r i a l a s s e r t i o n , - i n t e n s i v e t e r r i t o r i a l a s s e r t i o n , t h r e a t . - i n t e n s i v e i n t i m i d a t i o n , extreme a g g r e s s i o n -extreme c o n f l i c t between a t t a c k and f l e e - a t t a c k p r o b a b l e - d i r e c t a g g r e s s i o n - d i r e c t a g g r e s s i o n S t i r l i n g , 1965 Wing, 1946; B l a c k f o r d , 1963; S t i r l i n g , e t a l , 1970 Brooks, 1926; S t i r l i n g , 1965; S t i r l i n g et a l , 1970 B e n d e l l & E l l i o t t , 1967 S t i r l i n g , 1965; B e n d e l l et a l , 1967; Appendix 8 Appendix 8 S t i r l i n g , 1965; B e n d e l l et a l , 1967 B e n d e l l et a l , 1967 S t i r l i n g , 1965; Appendix 8 S t i r l i n g , 1965; Jump a t t a c k - d i r e c t a g g r e s s i o n S t i r l i n g , 1965; Appendix 8 - 9 9 -Crouch F l u s h Crouch & r u n Walk, r u n away C a l l s : - h i d e , p r e p a r e f o r f l u s h , • a n t i - p r e d a t o r b e h a v i o r , - i n t e r - s p e c i f i c s u b m i s s i o n - " e x p l o s i v e " f l i g h t from p r e d a t o r - i n t e n s i v e s u b m i s s i o n . Appendix 8, -moderate to i n t e n s i v e s u b m i s s i o n . Hoot song Ca-ca c a l l ( growl) -sex a d v e r t i s e m e n t , t e r r i t o r i a l a s s e r t i o n , moderate to i n t e n s i v e t h r e a t . - i n t e n s i v e t h r e a t , a t t a c k p r o b a b l y . B l a c k f o r d , 1 9 6 5 ; S t i r l i n g , 1 9 6 5 . S t i r l i n g et a l , 1 9 7 0 . FEMALES: P a t t e r n s and noses S i g n i f i c a n c e R eference N o r m a l n e u t r a l pose A l e r t pose F l u t t e r f l i g h t C h i c k defense Neck s t r e t c h Hard peck Rush and chase Crouch - i n d i f f e r e n c e - c o n f l i c t , meaning o b s c u r e . (see above) -a l o c a t i o n announce-ment, meaning o b s c u r e . B l a c k f o r d , 1 9 6 5 . - p r e d a t o r d i s t r a c t i o n , c o n t a i n s many seeming a g o n i s t i c elements. - i n t e n s i v e t h r e a t , a t t a c k p r o b a b l y . - d i r e c t a g g r e s s i o n S t i r l i n g et a l , 1 9 7 0 . (see above) S t i r l i n g , 1 9 6 5 . Appendix 8 . - d i r e c t a g g r e s s i o n - h i d e , p r e p a r e f o r f l u s h , i n t e r - s p e c i f i c sub-m i s s i o n . -100-F l u s h Crouch and r u n Walk, r u n away C a l l s :  "Hard" hen c l u c k s , ( c l u c k i n g , c l u c k c a l l e t c . ) Qua-qua (hen c r y ) - " e x p l o s i v e " f l i g h t from p r e d a t o r , i n t e r - s p e c i f i c submi -in 1 on. - i n t e n s i v e s u b m i s s i o n ^moderate to extreme s u b m i s s i o n . -used i n e n counters w i t h p r e d a t o r s but a l s o in a g g r e s s i v e e n c o u n t e r s • w i t h o t h e r g r o u s e . -sexual a d v e r t i s e m e n t , may be t h r e a t t o o t h e r hens. Appendix 8. S t i r l i n g , 1965. S t i r l i n g , 1 9 6 5 : B l a c k f o r d , 196J>, APPENDIX V I I I . New d i s c r i p t i o n s of b e h a v i o r p a t t e r n s . 1. Crouch and r u n T h i s p a t t e r n was observed i n a l l age and sex c a t -e g o r i e s and appeared t o be g i v e n i n response to human ob-s e r v e r s as w e l l as to o t h e r g r o u s e . I t was c h a r a c t e r i z e d by a low, h o r i z o n t a l body p r o f i l e , low neck and head, t i g h t con-t o u r f e a t h e r s , f u l l y f o l d e d , h o r i z o n t a l t a i l and i n c o n s p i c u o u s c r e s t , combs, wings and a i r s a c s . In t h i s pose, the b i r d r a n q u i c k l y between patches of v e g e t a t i o n where i t remained h a l f - c r o u c h e d , l o o k i n g about ' n e r v o u s l y ' b e f o r e moving on. T h i s p a t t e r n a p p a r e n t l y s e r v e s to reduce v i s u a l s i g -n a l l i n g when s u b m i s s i v e b i r d s r e t r e a t . I t was c h a r a c t e r --101-i s t i c of y e a r l i n g males when approached by h o o t i n g c o c k s , and was observed on many o c c a s i o n s i n both sexes when we approached. I t d i f f e r s from the t y p i c a l response toward p r e d a t o r s where the grouse g e n e r a l l y "crouches" c o m p l e t e l y and then " f l u s h e s " . I t i s one of the most important p a t t e r n s s i g n i f y i n g n o n - a g g r e s s i o n . Lumsden (1965) d e s c r i b e s a somewhat s i m i l a r p a t t e r n i n the s h a r p t a i l grouse, s i g n i f y i n g s u b m i s s i v e n e s s i n a d e f e a t e d cock a f t e r a f i g h t . 2. Head d i p T h i s p a t t e r n was g i v e n by e i t h e r sex d u r i n g a num-ber of poses and d i s p l a y s . The most common p a t t e r n i t was a s s o c i a t e d w i t h , i s the "neck s t r e t c h " , however i t was a l s o seen w i t h the " a l e r t " pose and v a r i o u s degrees of " f e a t h e r s p r e a d d i s p l a y " . Head d i p p i n g i n v o l v e d h o l d i n g the head e r e c t and w i t h a sharp, d e l i b e r a t e t h r u s t , d r i v i n g the c l o s e d b i l l downward a d i s t a n c e of about 1-5 i n c h e s . The r e t u r n o f the head to an u p r i g h t p o s i t i o n was always slower than the downward d i p . The p a t t e r n resembles a "hard peck d e l i v e r e d i n mid a i r and i s an important i n d i c a t i o n of a g g r e s s i v e n e s s . I t was one of the most common elements of a cock's b e h a v i o r p r i o r t o and d u r i n g a t t a c k s on the m i r r o r . I t was a l s o seen i n e ncounters of both sexes w i t h u s . 3. Hard peck T h i s p a t t e r n was s i m i l a r t o " p e c k i n g " ( S t i r l i n g , -102-1965), an a c t of d i r e c t a g g r e s s i o n which I renamed t o d i s -t i n g u i s h i t from " g e n t l e p e c k i n g " d e s c r i b e d below. 4 . G e n t l e peck T h i s a c t was seen used by a d u l t cocks o n l y . I t v/as used toward the dummy female which the cock was c o u r t i n g . I t was seen b e f o r e the commencement of c o p u l a t i o n and i t was seen most o f t e n a f t e r an i n i t i a l bout of attempted cop-u l a t i o n . I t c o n s i s t e d of v e r y g e n t l e , but d e l i b e r a t e pecks, g e n e r a l l y d i r e c t e d a t the neck or head of the hen but a l s o p e r i o d i c a l l y , a t the back, t a i l and wings. They were d e l i v -e r e d i n a s e r i e s , u s u a l l y two or t h r e e a second, which l a s t e d one to s e v e r a l seconds. The cock d e l i v e r e d the pecks from a number of d i f f e r e n t p o s i t i o n s - a n t e r i o r t o the hen, mounted on her back and from both s i d e s . T y p i c a l l y , a f t e r demounting from a c o p u l a t i o n attempt, he "head nodded" and moved toward her from the a n t e r i o r and commenced " g e n t l e p e c k i n g " b e f o r e remounting. The s i g n i f i c a n c e o f the p a t t e r n i s o b s c u r e . I t was r a r e l y seen i n the i n i t i a l phase of c o u r t i n g and t h e r e -f o r e , may never o c c u r i n u n d i s t u r b e d n a t u r e . I f e e l i t v/as d e r i v e d from the nape-grabbing movement d u r i n g c o p u l a t i o n and may f u n c t i o n t o e n t i c e u n w i l l i n g hens t o squat. 5. S t a n d i n g T h i s pose was a t y p i c a l p a r t of the " p r e c o p u l a t o r y -103-r u s h " d e s c r i b e d by S t i r l i n g (1965) but was not mentioned by t h a t a u t h o r . Most o b s e r v a t i o n s o f i t were t a k e n d u r i n g the c o u r t s h i p o f dummy females, but on one o c c a s i o n , a cock was seen t o use i t when c o u r t i n g a l i v e hen w i t h c h i c k s . Only h o o t i n g cocks use i t . The pose o c c u r r e d a f t e r the p r e c o p u l a t o r y r u s h and "whoot". The cock t h e n s t o o d c o m p l e t e l y m o t i o n l e s s i n f u l l " f e a t h e r s p r e a d d i s p l a y " , d i r e c t l y a d j a c e n t t o the hen. The pose was h e l d f o r from 5 seconds t o almost a minute. There was no obvious p o s i t i o n the cock c h a r a c t e r i s t i c a l l y adopted next t o the hen, except t h a t he was never seen " s t a n d -i n g " b e h i n d h e r . There was no obvious attempt by the cock t o d i s p l a y one, or both o f h i s neck r o s e t t e s . When break-i n g the pose, the cock t y p i c a l l y began t o "head nod" and move toward the hen's t a i l where mounting commenced. The purpose o f the pose i s undoubtedly i n t e n s i v e s e x u a l d i s p l a y t o the hen. The e l o n g a t e d s t a n d i n g sometimes observed w i t h dummy hens may have been an i n d i c a t i o n t h a t the hen n o r m a l l y e l i c i t s mounting by some s i g n a l ( s u c h as s q u a t t i n g ) which i s absent i n the model. 6 . Neck s t r e t c h T h i s a c t was d e s c r i b e d and named by S t i r l i n g , (1965). He d e s c r i b e d i t as the most i n t e n s i v e t h r e a t toward another g r o u s e . I t i s s i m i l a r to B e n d e l l & E l l i o t t ' s (1966) " t h r e a t pose", however because i t i s always d i s p l a y e d by a b i r d i mmediately p r i o r t o and d u r i n g an a t t a c k , I f e e l i t -104-i s more a c c u r a t e l y termed arr " a t t a c k i n t e n t i o n " than a t h r e a t . Hence the r e t u r n t o the o l d e r term. I t was gener-a l l y a s s o c i a t e d w i t h " p a c i n g " - nervous w a l k i n g back and f o r t h l a t e r a l l y t o the o t h e r b i r d . 7 . Jump a t t a c k T h i s a c t was a s m a l l hop t h a t cocks took immediately b e f o r e c o n t a c t i n g t h e i r m i r r o r image d u r i n g a f i g h t . S t i r l i n g - ( 1 9 6 5 ) d e s c r i b e s t h i s a c t , i n p a r t , as the "wing a t t a c k " . However, because cocks were seen t h a t .jumped i n t o the a i r w i t h o u t s t r i k i n g v/ith the wings ( i n s t e a d , s l a s h i n g downward v/ith the b i l l and f e e t ) , t h i s a c t must be r e c o g -n i z e d as s e p a r a t e from these l a t e r a c t s o f f i g h t i n g . I t appeared t h a t when cocks engaged another v/ith a "jump a t t a c k " , t h e y used i t i n com b i n a t i o n w i t h a number of d i f f e r e n t t a c t i c s . APPENDIX IX. s i d e 1. The d a t a c a r d f o r b e h a v i o r used toward o b s e r v e r . (If bird responding to observer, mark alt appropriate slots 'X') M O V E M E N T S A N D G E N E R A L B E H A V I O R ( A L L B IRDS) M: h. s -O B S E R V E R G E N L O C D A T E S E E N B E F O R E F L S H G E N : Sloop Sun Dust Defecate Sky -watch Stretch: wing P O S E S : Neutral M O V E M E N T S F: l . b - Y r - C h T I M E : S F n i l F U L L VIEW N O O S E A T M P TPreen Scratch Drink F e e d Shake Wing- f l ip Pant Gawk F l u f f neck, body, yawn Spont f lush F r e e z e A ler t Crest up T a i l up Crouch Ht pose D i s p l a y F l u s h immed Dis t walk D is t run C i r c l e obs. C i s t d is t obs F L U S H : T i m e to fl L n d tree L n d st, Ig N O O S E D : In hand: s t rg le , R E L E A S E : F l y Run Walk _ Mvmts : sec re t i ve , Dir f ly_ f. v i e w Dist f ly_ F l d is t F l loud wng L n d loud wng Ht of fit p a s s i v e Combs up P e c k Sound Sound D isp Vi Vl f Injured _ C H K B H V R : F l y immed Scatter & hide Crouch 8. f lush Squeal at f lush a) d i s t fr hon b) dist f iy c) in hnd: strg, pssve d) snd in hnd 1 I I I 7 I I I ^ I I I A I I I S I I I I T i m e to (irst ch i ck cnl . T i m e to F ' c o m c - i n . I - 1 0 5 -side. 2. MALES: Whinny used SOUNDS: Hoot H/rr Whoot (No.)_ _Gu-gu threat (No.)„ Sylbs. _Wing clap (No.) DISPLAY: Combs: nil y o r Neck: nil Vi Vl f Tai l : nil Vi Vi f To: obs F - B F - L ADM, Follow Nk stretch Hd bob Rush & Whoot Mount Tread Copulate Side to F: L R AGONISM: Agnst: obs ADM YRM F JUV, Rush Avoid Th pose Hd throw Pace Peck Wng strike Chase (dist) Victor stance ART. HOOT: H louder H/min Mve clsr Mvo off Display {Vi Vl f) MISC: Countour ftrs: tight loose raised Combs up in flgt Shoulder wht Wings under tail FEMALES: SOUNDS: Alarm elk Soft cluck Hiss Warning ru-tu Qua-qua cry Whinny Yuk Come-in call BROODY: Incubate Brood Walk off nst Fly off nst Brood cks Lead: 1 2 3 Defense: 1 2 3 R s p c h c o l l : nil 1 2 3 AGONISM: Agnst: obs ADF ADM JUV Chase (dist) COURT: Appr male Avoid male Dist chased Squat Copulate APPENDIX X. Methods of stalking grouse and observing behavior. The use of encounters between humans and grouse as situations from which to make behavior comparisons, de-pended on a fixed manner of finding and observing the grouse, We made over 5 , 0 0 0 encounters with birds during the study: Females Study area Males 1967 1968 1967 1968 M.Q.L. 541 571 528 504 C.B. 202 269 180 189 C.C. 1 9 5 288 195 166. The encounter could be divided into three phases. Variations from the general pattern generally occurred within the framework described. 1. Search: This was conducted by men working singly, each accompanied by a trained pointing dog. Each -106-was instructed to search within the boundaries of the study-area and to cover i t i n an even manner, on a grid of their own choosing. Workers varied s l i g h t l y i n their method of search according to their experience, endurance, etc. A l l generally walked slowly with the dog ranging i n front. An attempt was made to keep the dog within sight and under control at a l l times. There are " l i k e l y " areas to search for grouse and new observers were told of these at the outset. The average worker covered an estimated 5 miles per day (8 hours). At this rate, with an average effective search width of 5 0 0 feet, i t took each man at least 4- days (4—6) to obtain 100$ coverage of a 1,000 acre study area. Table A10-1 compares workers' success at locating grouse on the same habitat. Note that the variation between workers for any one month was consistently smaller than the variation between months for any one worker. Thus, people found grouse at approximately the same rate which depended mostly on the time of the year. In different populations, the same worker found birds at a rate which varied more than the variation seen between workers i n the same area. (For example, worker #1 located 31.2 birds i n 10 hours search at C.C. during May, and only 8.7 i n the same time at M.Q.L., also i n May.) 2. The point: The only function dogs served was to locate grouse which otherwise the worker would not have known were i n the v i c i n i t y . Four dogs were used, three Pointers -107-Table A10-1. Number of search at grouse M.Q.L. located i n by various 10 hours workers. of Worker Hooting male Silent male Lone female Brood female A l l birds 1. May 5.0 0 3.8 0 8 . 75 June 1.4 • 0 . 7 0 . 7 ' 4 .5 7.10 July 1.6 3.2 1.2 2.8 8.80 August 0 0.4 0.4 2 .7 3.60 2. May 7 . 7 3.0 3.0 0 13.40 June 5.6 5.8 2 .7 1.6 15.70 5 . May 7.4 3.0 3.0 0 13-40 June 3.0 4 . 1 5-6 0.8 13 .50 July 0.4 , 1 .9 1 .9 5.8 10.00 August 0 0 .9 2 .3 4.6 7.8 4. May 5 . 3 1 . 9 2 .3 0 . 9.4 June 2 .7 2.8 2.6 0.6 8.8 July 1.0 1.1 1.0 1 . 7 4 . 9 August 0 0.2 0 . 5 2.8 3.4 5 . May 6.4 1.8 1.8 0 10 c 3 June'. 2 . 5 3.4 2.6 0 . 9 10 .3 July 1.4 1.4 1.2 2.0 6.4 August 0 0.2 0 . 7 2.2 3 . 3 -108-and a Brittany Spaniel. Most "points" were made by scent. As can be inferred from Table A10-1, the dogs did not d i f f e r appreciably i n their a b i l i t y to locate grouse. 3. The stalk: During this procedure, the worker, and possibly the dog, moved slowly toward the bird's B U S - ' pected location to accurately locate i t . When the observer sighted or heard the grouse, the dog was stopped and was not active i n any of the further developments, While stalking, most workers crouched s l i g h t l y , walked carefully and s i l e n t l y , stopped every pace or two and searched the vegetation ahead, for the bird. Most stayed behind or abreast of the dog, releasing him to move forward only when the vegetation had been searched. In some cases, the dog was not needed for locating grouse. Hooting males, for example, could be located by following up the sound of their song. Also, grouse at times can be seen at some distance s i t t i n g on logs and stumps. In these cases, the dog was immediately stopped or heeled and the bird stalked d i r e c t l y . This brought the bird into f i r s t contact with the ob-server. At this time the observations on "general" behavior were f i l l e d i n on the card and the a r t i f i c i a l hoot was given. (See Appendix 9 . ) Stalking included manoevering to a position which allowed a clear observation of the bird from approx-imately 20-25 feet. In some situations, the active movement was provided by the bird, as when a brood hen moved i n to defend her chicks. -109-4-. The bird i n " f u l l view": This meant the bird could be seen i n entirety and any leg bands could be re- • corded. A l l observations on poses and behavior i n reaction to the observer, were made at this time. A "capture attempt" meant the noosing pole was extended and the noose moved to within 10 feet of the grouse. Small differences existed between the workers depending on situations, i n the methods of advancing the noose toward the bird and f i n a l l y slipping • i t over i t s head. 6. The flush: Grouse generally ended the situation by f l y i n g off. The flush distance was then paced off, distance moved by the bird while on the ground, time spent under observation etc. were recorded. In practice, most of the slots on the data card were f i l l e d i n after the encounter was finished. APPENDIX XI. Handling blue grouse. An early objective was to determine whether grouse reacted d i f f e r e n t l y to handling; i e : did some struggle while others did not? I also wished to know i f grouse dis -played different behavior when released. Moreover, because handling grouse i n the f i e l d can damage them, the routine of handling was standardized. When noosed,.grouse were quickly approached and trapped against the ground with the out-stretched hands to -110-q u e l l s t r u g g l i n g . As soon as p o s s i b l e , the b i r d was grasped by the humeral p o r t i o n of the wings and/or the l e g s . The noose was removed i m m e d i a t e l y . Throughout the h a n d l i n g , the b i r d was h e l d suspended by e i t h e r i t s wings or l e g s , or b o t h . The muscles and bones of the appendages were p e r f e c t -l y c a p a b l e o f s u p p o r t i n g the weight. Hanging ( e s p e c i a l l y by the l e g s i n the i n v e r t e d p o s i t i o n ) seemed t o q u e l l s t r u g g l i n g t o a l a r g e e x t e n t . By t h i s method b i r d s r a r e l y s u f f e r e d damage and l o s t v i r t u a l l y no body f e a t h e r s . F u r t h e r s o p h i s t i c a t i o n , p r i m a r i l y f o r w eighing, i n -v o l v e d p l a c i n g a h a rness around the humeral p o r t i o n of the wings, or around the l e g s j u s t above the f e e t . The h a rness was c o n s t r u c t e d of a s h o r t l e n g t h of p l y a b l e l e a t h e r w i t h a s l i t i n each end. One end was s l i p p e d around the base of the wings ( o r around the l e g s ) and t hrough the s l i t i n the o p p o s i t e end. G e n t l y r e l e a s i n g p r e s s u r e , the b i r d would hang from the thong a l l o w i n g an easy method f o r w e i g h i n g . Grouse were a l s o c o n t e n t to hang by one f o o t , from a l e g band d u r i n g w e i g h i n g . The method gave q u i c k e r , more a c c u r a t e r e s u l t s t han sack methods and d i d l e s s damage to the b i r d s . S m a l l young c o u l d be h a n d l e d s i m i l a r i l y , s i m p l y by s u b s t i t u t i n g a rubber e l a s t i c band f o r the thong. -111-APPENDIX XII. Test arena method. The following routine was followed i n subjecting males to the test arena situation: 1. A male was observed for several days u n t i l I was confident of locating the area inside his t e r r i t o r y from which he generally sang. 2. With a minimum of disturbance, I approached this position to within 50-60 yards, 'at a time of broadcast hooting, ( a l l tests v/ere given during the hours of 0500-1000 and 1800-2200). The "arena" was arranged on the ground i n a f l a t area, clear of vegetation for at least 2 yards square. a) Three plate glass mirrors, 40 cm x 60 cm. v/ere arranged i n a triangle, their faces outward. They were stood on their long edges and supported by three slotted blocks of wood (Fig. A12-1). b) An 8 - inch horn speaker was stood upright i n the center of the mirrors. c) A stuffed dummy female blue grouse v/as placed approximately 1% feet from the mirrors and d i r e c t l y i n front of one of the faces. She was mounted i n a "squatting" posture similar to that adopted by females during copulation ( S t i r l i n g , 1965), except that her head was elevated to render her more v i s i b l e . d) A 'Wightman E l e c t r i c ' transistorized amplifier (model CW-6) was attached to the speaker and situated i n a hide 10 to 20 yards from the s i t e . The hide was b u i l t of -112-vegetation, logs and rocks from the immediate area. Care was taken to cover, with vegetation, any part of the equipment that looked unnatural. This included the supporting blocks, the lead wire and the corners made by the joining of the mirror faces. Frequently I arranged the apparatus well i n advance of the test period to minimi z.-the effect.of any disturbance during the setting up pro-cedure. Thus, I set up i n the evening to test birds the .following morning. 3. Prior to each test, I recorded rel a t i v e l i g h t intensity, wind direction, wind strength, temperature, pre-c i p i t a t i o n f a l l i n g , amount of water on the vegetation, and relati v e song bird a c t i v i t y . The distance and direction to a l l hooting grouse was estimated. A l l hooting was timed and the number of hoot elements per song determined. 4. After remaining motionless for approximately "k hour, I commenced playing sequences of the female precop-ulatory "whinny" (described by S t i r l i n g , 1965). I played 0 sequence of ten to twelve whinnys every 5 minutes througho\ the test period. 5 . I timed the t e r r i t o r y holder's hooting before and throughout the test and noted and timed a l l his movemev A ' P h i l l i p s ' "casette" portable tape recorder was used to record data. 6. From the moment the cock appeared i n sight, I dictated a continuous recording of a l l his movements, c a l l ; and behavior patterns. This allowed an accurate timing of The t e s t arena. (Note dummy female) -114-every gesture throughout the test period. 7. I terminated tests when, either no further re-sponse could be e l i c i t e d from the male after 4 consecutive playings of the c a l l , or his response became a continuous sighting of the mirror. In the l a t t e r case, males were observed to damage their wings by st r i k i n g the mirror. The average test took approximately 45 to 60 minutes to perform. APPENDIX XIII. Interpretation of the test arena behavior; number of tests given. The set procedure outlined for presenting th i s test situation to grouse resulted i n a standard form of response. I divided this into three phases and presented the results accordingly. At the playing of the f i r s t "whinny" c a l l , the cock began the 'exploratory phase' of his response. When he saw the dummy female he began the 'courting phase'. As he became aware of his image i n one of the mirror faces, he entered the 'interactive phase'. Each of these phases had i t s characteristic behavior patterns. The f i r s t phase was dominated by the male's hoot song and his method of searching for the 'hen'. He either walked, ran or flew - s i l e n t l y , with hooting, or with loud "wing f l u t t e r s " . During this phase, the male was responding solely to the sound of the "whinny". (This c a l l was recorded i n the aviary at U.B.C. by Ian S t i r l i n g when females, i n - 1 1 5 -e a r l y s p r i n g , s q u a t t e d , s i g n i f y i n g s e x u a l r e c e p t i v e n e s s . The b e h a v i o r was g e n e r a l l y toward humans on which the hens seemed to be i m p r i n t e d . The c a l l has never been r e c o r d e d i n the w i l d . T h i s i m p l i e s t h a t i t c o u l d be an a r t i f a c t of the s i t u a t i o n i n the a v i a r y . S t i r l i n g ( 1 9 6 5 ) c o n c l u d e s t h a t i t i s a normal p r e c o p u l a t o r y c a l l o f the hen which f u n c t i o n s t o a t t r a c t , t h e male to h e r . However, t h i s has y e t to be s u b s t a n t i a t e d by o b s e r v a t i o n from the w i l d . T h e r e f o r e , the r e a s o n males respond t o the c a l l i s s t i l l a r e l a t i v e l y open q u e s t i o n . ) I t was assumed t h a t the cock's b e h a v i o r i n r e -sponse t o the c a l l c o u l d be i n t e r p r e t e d s o l e l y i n terms of s e x u a l d r i v e . C o u r t i n g was dominated by a c t s o f s e x u a l d i s p l a y and attempted c o p u l a t i o n s . T y p i c a l l y the cock e n t e r e d the s i t e w i t h a " p r e c o p u l a t o r y r u s h " and "whoot" and f o l l o w e d v/ith the t y p i c a l c o u r t i n g a c t s d e s c r i b e d elsewhere. T h i s o b v i o u s l y o c c u r r e d w i t h i n s i g h t of the m i r r o r image. V a r i o u s males broke from the c o u r t i n g phase i n t o i n t e r a c t i o n w i t h the m i r r o r , a t d i f f e r e n t times d u r i n g the c o u r t i n g p r o c e d u r e . A l l cocks q u i t e s u d d e n t l y s w i t c h e d t h e i r a t t e n t i o n from the dummy hen to the m i r r o r . T h i s happened at d i f f e r e n t l o c a t i o n s , but t y p i c a l l y the cock would mount the hen then q u i c k l y f l a s h i n t o " f e a t h e r s p r e a d " d i s p l a y w i t h h i s s t a r e f i x e d on the m i r r o r . A f t e r a second or two he e i t h e r r e -t r e a t e d or f l e w d i r e c t l y at the m i r r o r . Pew cocks r e t u r n e d t o the hen a f t e r i n i t i a l r e a c t i o n t o the m i r r o r . F i g h t s seemed to o c c u r most o f t e n i n the f o l l o w i n g -116-squence: 1. Feather spread d i s p l a y , p o s s i b l y hoot song 2. Head (throw) d i p , p o s s i b l y gu-gu c a l l 3c Neck s t r e t c h - back to 1, 2 or: 4. Pace - back to 1, 2, 3 o r : 5. Jump a t t a c k w i t h combination of t a c t i c s : a. double wing s t r i k e 'b. s i n g l e wing s t r i k e c. hard peck d. s l a s h i n g with, f e e t 6. 5 repeated or back to 1, 2, 3, 4. 7. R e t r e a t from s i t e o c c urred at a l l stages but was most commonly seen a f t e r 1. This phase was q u a n t i f i e d a c c o r d i n g t o the number of a g g r e s s i v e a c t s committed per u n i t time i n the arena. Pre-sumably d i f f e r e n c e s i n t h i s measure would r e f l e c t d i f f e r e n c e s i n the a g g r e s s i v e " d r i v e " of the i n d i v i d u a l s . A s i m i l a r r a t i o n a l was adopted by McBride (1958) who t e s t e d the aggres-s i v e n e s s of chickens and by Theberge (1971) who t e s t e d the aggressiveness of ptarmigan c h i c k s . The number of ag g r e s s i v e a c t s committed per minute i n c o n t r o l l e d s i t u a t i o n s i s emerging as a c r i t e r i o n f o r a g g r e s s i v e n e s s . Not a l l t hree phases were seen i n each t e s t performed. In some, the male d i s c o v e r e d the observer or was 'spooked' by the apparatus. Whenever some problem w i t h d e s i g n such as these, o c c u r r e d , the cock r e t r e a t e d and d i d not r e t u r n . On other o c c a s i o n s , l i v e females e i t h e r responded to the c a l l or were i n the v i c i n i t y beforehand. The cock then c o u r t e d the r e a l female i n s t e a d of the dummy. The most -Un-common complication was caused by s i l e n t , (yearling) males which also were attracted to the c a l l . The cock then re-sponded to this by chasing them from the area. Often the cock was apparently alerted to these intruders 'by nothing more than the sound of their walking through the vegetation. Some degree of success was experienced with 56 d i f -ferent t e r r i t o r i a l males, (Table A13-1). On instances where birds.were retested on subsequent occasions, only the f i r s t test v/as incorporated into the calculations. Table. A13-1. Aggressive tests to different males, 1967-68. Phases responded with: attempts exploration courting interaction (n) Study area M.Q.L. 40 25 11 11 C.B. 10 8 6 . 6 C.C. 45 23 10 8 APPENDIX XIV. Repeat tests of same male. Repeat mirror tests were given to five different cocks, (Table A14-1). The largest variation was 6.1 acts per minute between the f i r s t and th i r d test. This was a -118-change of approximately 30$. The t e s t e l i c i t e d a r e l a t i v e l y standard response and therefore subjecting each cock to sin g l e t e s t s was a v a l i d procedure. Table A14-2 shows the responses of two hi g h l y •aggressive' cocks and one 'non-aggressive' cock to the two t e s t s i t u a t i o n s used i n the study. Table A14-1. Repeat t e s t s by mirror method of same males. Male Study area Advance to Sex acts Aggres. whinny per min- a c t s / (ft./min) ute minute #1081 C.C. 1st: 3.5 0.4 1.7 2nd: 4.0 0.0 1.1 unhanded C.C. 1st: 3.8 1.5 2.1 2nd: 2.3 1.5 1.0 unhanded M.Q.L. 1st: 22.5 4.9 2.2 2nd: 20.0 4.5 3.4 #1651 M.Q.L. 1st: 70.0 6.4 12.0 2nd: 75.0 6.0 10.0 #1100 M.Q.L. 1st: 50.0 2.6 16.4 2nd: 43.6 3.0 14.0 3rd: 25.8 1.0 10.3 Table A14-2. Repeat tests of same male by two tests of . aggression. Male Aggressive Response acts/min to observer to mirror \ seen display*** flush before distance flushing* (feet) #1651 12.0 #1100 16.4 #1081 1 . 7 * - x: seen on ground, xx: f u l l view *** - x: xx: }£, xxx: f u l l , display X X X 2 0 X X X X 3 0 X X X 15 X X X 15 X X X 2 0 X X X 15 X X X X 2 0 X X X X X 2 0 X X X X 2 5 X X X 2 0 X X X 3 0 X 30 80 7 5 1 5 0 

Cite

Citation Scheme:

        

Citations by CSL (citeproc-js)

Usage Statistics

Share

Embed

Customize your widget with the following options, then copy and paste the code below into the HTML of your page to embed this item in your website.
                        
                            <div id="ubcOpenCollectionsWidgetDisplay">
                            <script id="ubcOpenCollectionsWidget"
                            src="{[{embed.src}]}"
                            data-item="{[{embed.item}]}"
                            data-collection="{[{embed.collection}]}"
                            data-metadata="{[{embed.showMetadata}]}"
                            data-width="{[{embed.width}]}"
                            data-media="{[{embed.selectedMedia}]}"
                            async >
                            </script>
                            </div>
                        
                    
IIIF logo Our image viewer uses the IIIF 2.0 standard. To load this item in other compatible viewers, use this url:
https://iiif.library.ubc.ca/presentation/dsp.831.1-0101885/manifest

Comment

Related Items