UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

The ecology and population dynamics of blue grouse in the sub-alpine King, D. G. 1971

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

Item Metadata

Download

Media
831-UBC_1971_A6_7 K55_3.pdf [ 9.27MB ]
Metadata
JSON: 831-1.0101920.json
JSON-LD: 831-1.0101920-ld.json
RDF/XML (Pretty): 831-1.0101920-rdf.xml
RDF/JSON: 831-1.0101920-rdf.json
Turtle: 831-1.0101920-turtle.txt
N-Triples: 831-1.0101920-rdf-ntriples.txt
Original Record: 831-1.0101920-source.json
Full Text
831-1.0101920-fulltext.txt
Citation
831-1.0101920.ris

Full Text

THE ECOLOGY AND POPULATION DYNAMICS OF BLUE GROUSE IN THE SUB-ALPINE by D. Go KING B.Sc. Un i v e r s i t y of B r i t i s h Columbia, 1964 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE i n the Department of Zoology We accept t h i s thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA 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 s h a l l make it f r e e l y a v a i l a b l e for reference and study. I further agree that permission for extensive copying of t h i s thesis for s c h o l a r l y purposes may be granted by the Head of my Department or by h i s representatives. It is understood that copying or p u b l i c a t i o n of t h i s thesis f o r f i n a n c i a l gain shall not be allowed without my written permission. The University of B r i t i s h Columbia Vancouver 8, Canada i Abstract This study was designed to follow up previous studies (Bendell and E l l i o t t 1967, Lance 1967, Zwickel and Bendell 1967) which suggested blue grouse regulated t h e i r numbers through j u v e n i l e mortality over winter, and to examine the population of.grouse that l i v e d t h e i r e n t i r e l i v e s on winter range. Grouse were observed and c o l l e c t e d i n the sub-alpine of Vancouver Island between May, 1965, and June, 1966. Data from the uplands were compared to grouse on lowland breeding ranges. The major findings were: (1) A low density and apparently stable breeding population l i v e d i n the sub-alpine with sex and.age r a t i o s and recruitment s i m i l a r to those of lowland populations. (2) A l l events of reproduction following spring migration were delayed approximately one month compared to the lowlands. Further, the nesting season was shorter by approximately four weeks. (3) Grouse i n the sub-alpine selected open forest and h i l l y areas as on the lowlands. (4) In winter, some males at l e a s t , l i v e d separately from hens and chicks. The males l i v e d i n the open forest of the upper elevations of the sub-alpine but, the habitat used by the hens and chicks i s unknown. (5) The main source of j u v e n i l e mortality, and hence population regulation, probably occurred i n autumn with f i r s t snow f a l l and/or brood break-up. Late winter behavioral i n t e r a c t i o n may also be important i n regulating numbers. (6) No f a c t o r of the sub-alpine was found that could explain the s i z e and success of lowland populations. There was some evidence to suggest that the q u a l i t y of food i n the sub-alpine may.be important to reproductive success on the lowlands. i i TABLE OF CONTENTS PART Page I INTRODUCTORY TOPICS . . . . . . . . . . . . . . . 2 Chapter 1. Introduction . . . . . . . . . . . . . . 2 Chapter 2 Study Area and Methods 5 (a) Location . . . . . . . 5 (b) Methods . . . . . . . . . . . . 7 Chapter 3 Habitat and Climate . . . . . . . . . . . . . . . 10 (a) Sub-Alpine Habitat . . . . . . 10 (b) Lowland Habitat 12 (c) Climate . . . . . 14 II RESULTS AND CONCLUSIONS . . . . . . 16 Chapter 4 Migrations . . . . . -16 (a) Spring . .16 (b) Autumn 17 Chapter 5 Habitat Selection by Residents . . . 24 (a) Males . 25 (b) Females . 30 (c) Winter . . . . . . . . 32 Chapter 6 Reproduction . . . . . . . . . . . . . 36 (a) Influence. of Weather 36 (b) Hooting Display . . . . . . . . . . . . . 39 (c) T e s t i c u l a r Cycle . . . . . . . 43 (d) Females . . . . . .. . . . . 47 (e) Brood Size and Growth 50 i i i Page Chapter 7 Populations .• . . . . . . 55 (a) Males 55 (b) Females . . . . 60 (c) Production 60 (d) M o r t a l i t y Factors 61 DISCUSSION . . . . . . 65 Cr i t i c i s m s of the,Data . . . . . . . . . . 65 Size and Importance of the Sub-alpine v? Grouse Population . . . . . . . . . . 67 Habitat Selection Compared to the Lowlands 69 The Late Breeding Season.in the Sub-Alpine 70 Seasonal Migrations 72 Population Regulation on the Winter Range 74 SUMMARY . . . . . . 79 L i t e r a t u r e Cited 83 APPENDIX A Grouse Co l l e c t e d i n the Sub-alpine from May, 1965, through June, 1966, Divided i n t o Adult, Yearling, and Juveniles and Sex . . 90 APPENDIX B S t r u c t u r a l D e t a i l , Per Cent of Study Area, and A l t i t u d i n a l Range of the Six Sub-Alpine Habitats Shown i n Figure 2 with a B r i e f Description of Each . . 92 APPENDIX C Structure of the Habitat Types of Lowland Blue Grouse Range 99 i v Page APPENDIX D A Chart Showing Sub-alpine Clim a t i c Data f o r May 1965 to May, 1966: R a i n f a l l , Snow Pack, and Temperatures . . . . . . . . . . 101 APPENDIX E Food of Grouse i n the Sub-alpine with Tables and a.Brief Description of Major Items.. . 104 APPENDIX F Moult Patterns of Primary Feather of Sub-alpine Grouse 116 APPENDIX G Observations on Hens, Nests, and Broods, Spring and Summer, 1965 and 1966 122 APPENDIX H A Table of Chicks and Eggs used i n Estimating Hatch Dates and Time of Laying 124 APPENDIX I The Distance to Nearest Neighbour of Hooting Males on Beecher and Washington i n 1965, and on, Browns i n . 1966 126 APPENDIX J The Per Cent.of Yearlings i n Undisturbed Popu-l a t i o n s i n the Sub-alpine and on.the Low-lands; and the Replacement of Shot T e r r i t o r y Holders within the Same and i n the Following Year . . . 128 APPENDIX K Predation Observed i n the Sub-alpine . . . . . 130 APPENDIX L Parasites of Grouse Collected i n the Sub-alpine i n 1965 and 1966 132 APPENDIX M The Seasonal;Change in.Amount of Fat of Grouse i n the, Sub-alpine . . . 134 APPENDIX N Size of the Weekly Samples of Sub-alpine Grouse Used i n . P l o t t i n g Change i n T e s t i c u l a r Volume , through the Year 138 LIST OF TABLES TABLE Page. 1 Grouse Collected on Forbidden Plateau Between May, 1965, and June, 1966 „ . •. . . . . . . . 8 2 A Comparison of Sub-alpine and Lowland Habitat Types , . 13 3 Monthly Temperature, Rainfall, and Snow Pack of the Sub-alpine for May, 1965, to May, 1966 . . . . . . 14 4 Orientation of Grouse;Tracks During Spring Movements, 5 Use of Sub-alpine Habitats by Migrating Grouse . . . . . 22 6 Number of Grouse in Each Sub-alpine Habitat During the Breeding Season (in Per Cent) 24 7 Habitat Selection by New Males and Yearlings Compared to Old Males . . . . o . . . . . . o . . . . . . . 27 8 Number of Grouse Collected in the,10 Days Before.and After May 18 in 1965 and 1966 . . . . . . . . . . 41 9 The Dates when Yearling Hooters were Collected . . . . 42 10 Average Brood Size in the Sub-alpine and Lowlands In 19 6 5 e o o e « o o o o • a ' o » e s o e • • • • • 30 11 Density of Grouse,in the Sub-alpine and on the Lowlands 56 12 Comparison of the Main Periods of Laying in the Sub-alpine and Lowlands with Average Maximum and Minimum Temperatures in the Two Weeks.Prior to Laying, and with Snow Cover and Vegetative Growth at Laying . . 71 v i LIST OF FIGURES FIGURE ' Page 1 Location of the Three Main Sub-alpine Study Areas and the Nearest Lowland Study Area 6 2 P r o f i l e s of the Sub-alpine Habitat Based on A l t i t u d e , Tree Cover, Slope, and Rock Outcrops . „ . „ . . . . 11 3 The Change i n Number of S i l e n t Males, Lone Hens and Broods Observed during Autumn Migration i n Sub-alpine . . . 18 4 Areas of.Concentrated Autumn and Spring Migrations i n Relation to C l i f f s and Canyon Walls; and the Location of Grouse Banded on.the Lowlands and Recovered i n the Sub-alpine . . . . . . . . „ . » . . . . . . . . . . . . . . 20 5a Location of Male T e r r i t o r i e s and Habitat Types on Mount Washington . . . „ . . . . . . . ' . . • . . . . . • . . . . 28 5b Location of Male T e r r i t o r i e s and Habitat Types on Mount 6 A Comparison of the Timing of some Events of the Breeding Season Between the Sub-alpine and Lowlands . . . . . 37 7 A Comparison of Spring Temperatures between the Sub-alpine and the Lowlands i n 1965 and 1966 38 8 Seasonal Change i n Hooting Males Through the Summer i n the Sub-alpine and on the Lowlands , . , , , < , , . . . 40 9 Seasonal V a r i a t i o n i n Average Volume,of the Testes of Adults and Yearlings of the Sub-alpine compared with the Lowlands . . . . . . . . „ • . . . 45 10 A Comparison of Sub-alpine and Lowland Hatch Dates for 1965 « o » 9 « * a c * « e » c » c « o e • ' • • • « * A9 v i i FIGURE Page 11 A Comparison of the Growth of Chicks in the Sub-alpine and on the Lowlands 52 12 A Comparison.of the Range of Body.Weights of Adult Males from the Sub-alpine and Lowland . . . . . . . . 54 13 A Comparison.of the Per Cent of Autumn Chicks Lost over Winter and Early Winter Snow F a l l 76 14 Ridgetop Habitat of Mount Washington . . 95 15 C l i f f Habitat on Mount Beecher . . . . . . . . . . . . 95 16 Photo of Parkland Habitat Showing Open Space Between Tree Clumps . . . . . . . . . . . . 95 17 Open Parkland Habitat of Higher Elevations . . . . . . 96 18 Dense Forest Habitat of the Lower Sub-alpine . . . . . 96 19 A Rock Outcrop in Open Forest Habitat . . . . . . . . . 96 20 Winter Range in.Late February . . . . . . . . . . . . . 97 21 Blue Grouse RoostTree in January . . . . . . . . . . . 97 22 Roost Tree in March . . . . 97 23 Immature Sub-alpine Trees Encased in Snow . . . . . . . 97 24 Blue Grouse Winter Range in January .98 25 A Nest Location on.a Rock Outcropping at 4000 Feet . . 98 26 Typical Sub-alpine Brood Range . . 98 v i i i Acknowledgments Dr. J , F. Bendell, my supervisor, f i r s t suggested my thesis problem to me. Throughout the project he f r e e l y gave of h i s time i n much h e l p f u l discussion and advice; provided materials, labora-tory space, and a t e c h n i c a l a s s i s t a n t ; and permitted me free access to unpublished data i n h i s files„ To him I am most g r a t e f u l and wish to express my deepest appreciation. I would also l i k e to extend thanks to the members of my committee, Dr. H„ D„ Fisher, Dr. R. H. Drent, Dr. V. J . Krajina, and Dr. C. V, Finnegan, for t h e i r assistance and advice at d i f f e r e n t stages i n t h i s study and i n the preparation of t h i s manuscript. And a s p e c i a l thanks to Dr. W. S. Hoar, Head of the Department of Zoology, fo r permitting me to take time out from my work on an assignment with Canadian U n i v e r s i t y Services Overseas. Many i n d i v i d u a l s a s s i s t e d i n the c o l l e c t i o n and analysis of the data, and i n innumerable other ways. Space i s i n s u f f i c i e n t to thank each i n d i v i d u a l l y , but I would l i k e to s i n g l e out a few: Peter Prince, without whose help the f i r s t summer would not have been a success, Dr. F, C. Zwickel, who provided free access to h i s unpublished f i l e s on Comox Burn, Dr. J , R. Adams, who checked my blood smears f o r pa r a s i t e s , and i d e n t i f i e d endoparasites. Dr. K. Beamish, who provided i d e n t i f i c a t i o n s for various pieces of plant material. Dr. G. G. E. Scudder, who i d e n t i f i e d the inserts taken from crops. And Mrs, H. S. Chapman, who provided good food and a warm bath between excursions onto the winter range. To a l l , I am most g r a t e f u l . Without the f u l l co-operation of personnel of Crown Zellerbach of Canada (Comox Division) and of Mount Washington Mines Limited, t h i s project could not have proceeded. Both companies permitted me f u l l use of t h e i r roads, provided s h e l t e r , p a r t i c u l a r l y i n winter, and helped i n many other ways. A s p e c i a l thanks to both. F i n a n c i a l assistance was contributed through a grant from the National Research Council of Canada and a scholarship from the Canadian W i l d l i f e Services. L a s t l y , a s p e c i a l word for my dog, S a l l y , without whose u n t i r -ing and f a i t h f u l work and companionship t h i s study, e s p e c i a l l y the winter aspect, would not have been p o s s i b l e . THE ECOLOGY AND POPULATION DYNAMICS OF BLUE GROUSE IN THE SUB-ALPINE Part I Introductory Topics Part II Results and.Conclusions Discussion Summary PART I INTRODUCTORY TOPICS 1. Introduction This thesis i s part of a continuing study into the .factors which regulate the abundance and distribution of the Sooty Blue Grouse, Dendragapus obscurus fuliginosus (Ridgway). Basic aspects of the biology arid ecology.of the Sooty Blue Grouse are given by Bendell (1954, 1955a, 1955c), Fowle (1960), S t i r l i n g (1965, 1968),. Simard (1965), and King (1968). And specific studies into the factors which regulate the abundance and distribution are reported by E l l i o t t (1965), Zwickel (1965), Bendell and E l l i o t t (1966, 1967), Zwickel and Bendell (1967a), and Lance (1967). A l l were carried out during April through September at low elevation on Vancouver Island. The key result of these studies was to show that the death rate or dispersal of juveniles between autumn and early spring is the most important parameter involved in.the regulation of breeding densities. A similar conclusion was arrived at for blue grouse,in Alberta (Boag 1966), ptarmigan (Lagopus sp.) in Scotland (Jenkins 1963, Watson 1965) and Montana (Choate 1963), spruce grouse (Canachites canadensis) (Robinson 1969), and the song sparrow (Melospiza melodia) on Mandarte Island (Tompa 1964). Mortality of young between time of leaving their parents and entering the breeding population, according to Chitty (1964, 1967), Bendell (1970) and Lack (1966), i s a general phenomenon 3 r e g u l a t i n g animal p o p u l a t i o n s . With t h i s background, the broad objec-t i v e of t h i s t h e s i s was to study the blue grouse i n undisturbed h a b i t a t at high e l e v a t i o n s where the grouse w i n t e r and where some b i r d s spend t h e i r e n t i r e l i f e ; and to determine the f a t e of the chicks a f t e r the breeding season. Sooty Blue Grouse occupy lowland h a b i t a t , l a r g e l y created by log g i n g and burning, f o r the breeding season only. In l a t e summer the grouse r e t i r e to the sub-alpine to w i n t e r and do not r e t u r n to the lowlands u n t i l the f o l l o w i n g March. P r i o r to t h i s study there was no extensive examination of grouse at high e l e v a t i o n i n e i t h e r w i n t e r or summer. General observations on the behaviour and h a b i t s of blue grouse i n w i n t e r had been made by s e v e r a l workers (Skinner 1927, Bent 1932, M a r s h a l l 1946, Wing 1947, Caswell 1954, Rogers 1968, and o t h e r s ) . The main conclusions,of these i n d i v i d u a l s were that the grouse spend most of the w i n t e r i n coniferous trees and that they feed l a r g e l y on c o n i f e r needles. S p e c i f i c s t u d i e s i n t o the q u a l i t y of the w i n t e r food i n r e l a t i o n to grouse numbers have been attempted by Hoffmann (1961) and Boag and Kiceniu k (1968). Zwickel and Bendell (1967a) say that blue grouse populations seem to respond to changes ( l o g g i n g , burning, regeneration) of the summer range i n a density-dependent manner. These authors suggest.the c o n t r o l may be one or a combination of some form of autumn or wi n t e r t e r r i t o r i a l behaviour as occurs i n red grouse (L,. lagopus s c o t i c u s ) (Jenkins et a l . 1963), p r e d a t i o n , or s t a r v a t i o n . B e n d e l l and E l l i o t t (1967) suggest.that the q u a l i t y of the summer range, p a r t i c u l a r l y food 4 quality, may affect chicks that go into the winter and influence their chance of su r v i v a l ; that there may be interaction between hen and chicks at the time of brood break-up which taken along with the quality of young produced on a par t i c u l a r summer range may be important to population regulation. On the other hand, Lance (1967) says mortality over winter and the process of regulation occurs independently of conditions on the summer range although he has no data to support this view. However, l i k e Bendell and E l l i o t t , he believes that i n t r a s p e c i f i c h o s t i l i t y between hen and chick over winter probably regulates r e c r u i t -ment. In following up these arguments, I attempted to fi n d how and when chicks died i n winter, which ones died, and ultimately, how blue grouse regulate t h e i r numbers. I was not able to f u l f i l t h i s objective, however, p r i n c i p a l l y because of the i n a b i l i t y to find chicks through the winter. Most of the thesis i s concerned with the grouse that remained at high elevation through the year. I asked: how large a population l i v e d and bred i n the sub-alpine and what was i t ' s structure? What was the d i s t r i b u t i o n of the grouse i n the sub-alpine and how was i t related to the sub-alpine habitat? What production occurred i n the sub-alpine and was i t important to grouse numbers? Was there interchange between the sub-alpine and lowland breeding populations? How were the grouse distributed during the winter and what habitat did they use? And, was there a population of surplus yearling males i n the sub-alpine? This f i n a l question was framed to learn i f some yearling males did not descend to lowland breeding grounds as suggested by Beer (1943), Bendell 5 (1955a), Bendell and E l l i o t t (1967), and others, although Zwickel and Bendell (1967a) present evidence that suggests that a l l yearling males do descend. Throughout the thesis my results are compared with those from the lowland studies. Similarities and differences are stressed with an attempt to explain them. 2. Study Area and Methods (a) Location The main study areas were on Beecher (Becher) Mountain and Mount Washington in the Forbidden Plateau region of Vancouver Island, British Columbia (Figure 1, page 6). In the second year, Browns Mountain, be-tween Beecher and Washington, was also used. The area searched on Mount Beecher was 5.60 sq. mi.; on Mount Washington 2.60 sq. mi.; and on Mount Brown 0.85 sq. mi.; a total of 9.25 square miles. Forbidden Plateau i s about 3500 feet above sea level with peaks to 5200 feet. To the east, elevations drop quickly to lowlands under 1500 feet. To the west, mountainous terrain extends many miles with peaks to 7000 feet occurring 8 to 10 miles away. Valleys and ridges of the plateau run generally from the southeast to northwest but these are disected by many rivers and deep canyons. These areas were selected because they appeared representative of the sub-alpine habitat of Vancouver Island and were thought to be the wintering grounds for grouse from lowland breeding ranges. Further, they were near Comox Burn (2 miles) and Quinsam Lakes (16 miles) where Figure 1. Location of the three main sub-alpine study areas and the nearest lowland study area. 7 important lowland studies of blue grouse were made (Bendell 1954, E l l i o t t 1965, and Zwickel 1965). It was hoped that birds banded on these.lowlands would be found on these uplands in migration (Bendell and E l l i o t t 1967) and in winter. (b) Methods My method of study was to search, observe, and collect grouse. Pointing dogs were used throughout. Field work began in May, 1965, and ran through to June, 1966. I was in the f i e l d almost every day except when weather conditions made f i e l d work extremely d i f f i c u l t . An attempt was made to give a l l parts of the study areas equal search, un t i l i t became apparent that few, i f any, birds lived in the areas of dense forest, then most time was concentrated in the more open habitat. In autumn and through the winter, after i t became apparent that many grouse were passing through my study area, some time was spent searching other sub-alpine areas for grouse. Moreover, in late autumn and early spring I visited nearby lowlands to monitor the departure and arrival of grouse from them. At the beginning of the study I had hoped to noose and band (Zwickel and Bendell 1967) some grouse to get data on territory size and movements and on seasonal changes in behavior. However, most grouse, particularly males, were found high in trees and were impossible to catch. (This was before the use of recorded calls (Stirling and Bendell 1966) had been fully developed,as a technique.for capturing grouse). And as data on age, weight, and breeding conditions were wanted, the grouse were collected. After a grouse was removed, ,search was continued in the area for any replacements or others that might appear. These, too, were collected. During the study I collected 128 grouse (Table 1) (Appendix A) and recorded for each: date and hour, an identification number, age, sex, weight (triple-beam balance to nearest gram), activity, location, vegetation within a radius of 25 yards, weather, distance to other birds and known fixed points, and any other relevant observations. TABLE 1 Grouse collected on Forbidden Plateau between May, 1965, and June, 1966 Age* Females Males Total Adult 9 81 9G Yearling 6 17 23 Juvenile 6 9 15 128 * Juvenile was.a bird under 7 months of age; yearling, a bird 7 to 15 months; adult , a bird over 15 months. Blood films were taken from many birds and.all gonads were placed in Bouin's solution. The grouse were then frozen for later examination. As far as possible, the same information was recorded for a l l other grouse observed. At examination in the laboratory, measurements were made of the amount of fat on the body, the crop contents were analysed, the entire 9 gut was searched for parasites, and weights were taken of the gizzard, heart, caeca, and l i v e r . The s i z e of the gonads was measured volumetri-c a l l y , the primary moult was recorded, and the blood smears given a preliminary survey for p a r a s i t e s . A maximum-minimum thermometer (located 5 feet o f f the ground and sheltered) was used to record the d a i l y high and low temperatures from May through September, 1965, From October through to May, 1966, temper-atures were recorded only f o r those days spent i n the f i e l d . R a i n f a l l was recorded d a i l y and measured i n inches using a standard r a i n gauge. The accumulation of snow on the ground and the rate of spring melt were recorded r e g u l a r l y at stations at three elevations (1500, 3000, and 4500 feet) and i r r e g u l a r l y at several other s t a t i o n s . An evapori-meter was set up for June through August, the f r o s t - f r e e period. In the summer of 1965, data on the sub-alpine habitat were taken at selected points throughout the study areas. The following were examined: extent of tree cover, tree height, extent of ground cover by t a l l and short (over and under 12 inches) shrubs, the slope of the t e r r a i n , the s i z e and kind of openings, and exposure. Exposure refers to the command of view the s i t e offered. A treeless ridgetop offered greatest exposure and small forest clearings the l e a s t . Similar data were taken at the l o c a t i o n of every grouse observed and c o l l e c t e d . A e r i a l photos were used to determine the extent of the general patterns of vegetation found i n the ground survey. 10 3. Habitat and Climate (a) Sub-alpine Habitat The study area was i n the Sub-alpine Mountain Hemlock Biogeo-c l i m a t i c Zone (Krajina 1965, 1969), however, the area was not homogenous throughout due to v a r i a t i o n s i n topography. The lower l i m i t s of the zone (3100 to 3500 feet) were e a s i l y recognized by the presence or absence of mountain hemlock (Tsuga mertensiana) (Brooke 1966, Peterson 1964). The zone i s a heavy f o r e s t at lower elevations but thins above 4000 feet where trees are found i n scattered clumps separated by meadows of low shrubs. Differences i n the geology of the d i f f e r e n t mountains of the study area produced important differences i n t h e i r topographies. Mount Beecher and Browns Mountain are extremely broken and rugged igneous rock (Hardy 1953). There are many rock outcrops and c l i f f s barren of anything except mosses, l i c h e n s , and a few herbs. These openings int e r r u p t the forest p a r t i c u l a r l y at the lower elevations (under 4000 f e e t ) . (Figure 15, Appendix B). On the other hand, a large portion of Mount Washington i s underlain by e a s i l y eroded sedimentary rock (Hardy 1953) r e s u l t i n g i n ridges with gentle slopes, few outcrops and, hence, few forest openings. I c l a s s i f i e d the habitat of the study area i n t o s i x types: Dense Forest, Open Forest, C l i f f , Ridgetop, Parkland, and Open Parkland (Figure 2, page 11) on the basis of the density of tree cover, the degree of slope, and the extent of rock outcrops. In areas undisturbed by rock outcrops, f o r e s t was continuous below 4000 feet (Dense Forest) Figure 2. Profiles of the sub-alpine habitat based on altitude, tree cover, slope, and rock outcrops. The numbers are the amount of each habitat in a l l areas in per cent. R O C K O U T C R O P S G E N T L E S L O P E S T E E P S L O P E R IDGE O V E R 4 0 0 0 F E E T U N D E R 4000 F E E T PARK LAND O P E N P A R K L A N D C L I F F R I DGE 8 D E N S E F O R E S T O P E N F O R E S T 32 11 POND 33 O 12 with clumped forest above this elevation (Parkland). Forest interrupted by,outcrops on gentle slopes (under 15 degrees) formed the Open Forest, and on steep slopes, the C l i f f type. Outcrops in Parkland were not important except at high elevations (over 4500 feet) on mountain tops where a very open barren habitat (Open Parkland) was found. Acute ridges within the parkland formed the Ridgetop type. Diagrammatic figures of each type are found in Figure 2 (page 11) while plates of their structure are in Appendix B. (b) Lowland Habitat The lowland habitat needs description for comparisons between i t and the sub-alpine are frequently made. The lowlands were once dense conifer forest (Krajina 1969) but are now a mixture of open, prairie-like landscape dotted with charred logs and stumps among young stands of conifers. This is the result of logging, repeated burning, and planting (Bendell and E l l i o t t 1966, Zwickel 1965). The replanting created an unnatural plant succession, and habitat types which Bendell and E l l i o t t (1967) classified as Very Open, Open, Dense, and Very Dense. These were based primarily on the size and density of the con-ifers which covered approximately 2, 28, 45, and 75 per cent of the ground, respectively. Logs and stumps, shrubs, and herbs (plants without perennial woody tissue above ground (Peck 1961)) were important elements of the habitat. Bare rock and s o i l accounted for 12 to 50 per cent of open areas though less than 5 per cent in dense types (see Appendix C for details). It i s d i f f i c u l t to compare the sub-alpine habitat types with those on the lowlands. The conifers in the lowlands were mostly under 13 20 feet while trees in the sub-alpine, except on exposed ridges and at high elevations, were over 20 feet. Further, there were virtually no deciduous trees in the sub-alpine, although these made up about half the shrub cover on the lowlands. Finally, herbs were unimportant in the sub-alpine but were important in a l l habitat types on the low-lands. Nevertheless, in a broad comparison of the sub-alpine and lowlands, there are some structural similarities (Table 2). However, the sub-alpine C l i f f and Ridgetop types have no counterparts in the TABLE 2 A Comparison of Sub-alpine and Lowland Habitat Types Sub-alpine Type Comparable Lowland Type Open Parkland Very Open Parkland Open Dense Forest Very Dense Open Forest Dense C l i f f -Ridgetop -r o l l i n g lowlands as topography i s as important as vegetational struc-ture- in their composition (Figure 2, page 11). However, Bendell and E l l i o t t (1966) ,did find that the grouse preferred the knolls and slopes to basins and level areas within their habitat types. (c) Climate The sub-alpine zone i s characterized by snow cover which l a s t s 7 to 9 months and a cool short summer (Krajina 1965). Table 3 summarizes the average monthly minimum and maximum temperatures (°F), t o t a l monthly r a i n f a l l , and average monthly snow pack f o r the study area for May, 1965, through May, 1966 (Appendix D for d e t a i l ) . The TABLE 3 Monthly Temperature, R a i n f a l l , and Snow Pack of the Sub-alpine f or May, 1965, to May, 1966 Av. Monthly Temp . (°F) R a i n f a l l Snow Pack ( f t . ) Min. Max. To t a l (in.) 4500 f t . 1500 f t 1965 May 32 44 1.5 4.0 -June 42 64 1.2 1.0 -July 49 64 3.9 - -Aug. 50 66 4.4 - -Sept. 38 58; Tr. - -Oct. 34 46 (4.0) 0.2 -Nov. 27 35 - 0.5 -Dec. 19 27 - 6.0 0.5 1966 Jan. 20 28 - 10.0 2.5 Feb. 22 30 - 14.0 4.0 Mar. 24 35 - 14.0 -A p r i l 26 41 - 14.0 -May 31 44 - 11.0 -15 warmest month was August and the coolest was December, although the hottest day (90 degrees) occurred i n July and the coldest (15 degrees) i n February. From November through May a l l p r e c i p i t a t i o n f e l l as snow. In 1965, maximum snow depth was 9 feet (Snow Survey B u l l e t i n for March 1965) reached i n February, but i n 1966, i t was 18 feet reached i n the t h i r d week of March. In 1965, a l l snow melted by the f i r s t of July but i n 1966, snow remained to l a t e August (Lance, pers. comm.). In 1965, the f i r s t f r o s t came i n mid-September and the f i r s t snow on October 14. When daytime temperatures above free z i n g returned i n l a t e March (1966), snow melted o f f ridge tops and exposed out-croppings ending a period of approximately four months when the entire ground surface was covered i n snow. At 1500 feet elevation, snow came seven weeks (December 10) l a t e r , f e l l i n smaller q u a n t i t i e s , and disappeared four months e a r l i e r (March 30) than at 4500 feet . Hence, on the basis of snow pack and temperature, 1966 appeared less favourable than 1965, and high elevations l e s s favourable than low elevations to grouse. PART II RESULTS AND CONCLUSIONS 4. Migrations (a) Spring In spring, blue grouse migrate to summer lowland ranges and breed. This movement was studied i n the sub-alpine i n 1966 by recording the number and the d i r e c t i o n i n which grouse were, travell-? ing during early spring. A clear change i n behavior took place about March 25th when tracks very suddenly became oriented mostly towards the east (Table 4). This o r i e n t a t i o n of t r a v e l (highly s i g n i f i c a n t 2 change, Chi =81.7, 3df) towards the lowlands continued through the f i r s t week of A p r i l . In addition, 3 grouse that had been on the study area for several weeks disappeared, and 7 new grouse appeared i n another area. However, by A p r i l 11th, new grouse sign and new grouse TABLE 4 Orientation of Grouse Tracks during Spring Movements, 1966 Date Tracks Observed Per cent Headed East Before March 25 37 30 March 25 - A p r i l 10 38 89 A p r i l 11 - A p r i l 30 13 23 17 became scarce. Thus, the spring migration which had started about March 25th was e s s e n t i a l l y completed i n a period of about 15 days. This observation was supported by f i e l d work on the lowlands where no grouse were found during search on March 26th but 3 males were found on A p r i l 3rd. Thereafter, grouse became numerous and Lance (pers. comm.) noted that most grouse had arr i v e d on the lowland summer range by the second week of A p r i l . During the spring migration, the grouse appeared to f l y onto the study area from the west, walk to the crest of slopes, then f l y towards the lowlands to the east. They t r a v e l l e d alone and i n s t r a i g h t l i n e s . When ascending they often went long distances (up to 1500 feet) on foot. Such behavior was also observed by Anthony (1903) and Caswell (1954). No song (hooting) was heard during these movements. (b) Autumn The reproductive season ends with migration back to winter range. This movement was recorded by noting the change i n numbers of males, lone hens, and hens with brood from June through October ( F i g -ure 3, page 18). U n i d e n t i f i e d birds were not included except where sex was not needed. The curves i n Figure 3 are running bi-monthly averages. Two curves are shown f o r changes i n numbers of hens with brood observed: Curve A represents, all.broods seen while Curve B was drawn to show changes i n number of lowland migrants only. Broods seen i n July (except one) and two i n August were sub-alpine residents. Early i n the autumn migration i t became apparent that most grouse were passing through the study area apparently headed f o r the RUNNING BI-MONTHLY AVERAGES MAY JUNE JULY AUG SEPT OCT M O N T H Figure 3. The change in number of silent males, lone hens, and broods observerved during autumn migration in the sub-alpine. The points are bi-morithly averages and the lines are running means. A - all broods; B- sub-alpine broods only. 19 higher mountains 5 to 10 miles far t h e r west. Two adult males banded on the lowlands were c o l l e c t e d on the western edge of the study area. One was c o l l e c t e d on August 11th, 4.8 a i r miles southwest of i t s band-ing point and the second 3.4 miles (Figure 4, page 20). Only a small number of grouse remained on the study area for the winter and these w i l l be considered l a t e r . Migrating males were f i r s t detected i n the uplands about mid-J u l y which coincided with the s t a r t of t h e i r departure from the lowlands (Bendell and E l l i o t t 1967), Numbers slowly b u i l t to a peak i n mid-August though the above authors say that almost a l l male grouse have l e f t the lowlands by August 1st. The migration of males i n t o the sub-alpine did not terminate u n t i l early September, two weeks a f t e r the l a s t males l e f t the lowlands (Bendell and E l l i o t t 1967). These data suggest there was a two-week delay f o r most males between departure from the lowlands a n d i a r r i v a l i n the sub-alpine. In*this period, short excursions through the 1 to 2 miles of heavy f o r e s t between the lowlands and sub-alpine, f a i l e d to discover any grouse. I t appears, therefore, that males did not leave the summer range as soon as reported. Lone hens (broodless hens) migrate at the same time as the males. Seventy per cent (19/26) of the lone hens observed a f t e r mid-July were observed i n August. These data confirm the observations of Bendell and E l l i o t t (1967) and Boag (1966) that lone hens migrate at the same time as the males and e a r l i e r than hens with brood (below). On the other-hand, I found no evidence to i n d i c a t e that some hens that go to the low-land breeding range return to the sub-alpine by June as Zwickel (1965) suggested. Figure 4« Areas of concentrated autumn and spring migrations in relation to c l i f f s and canyon walls; and the location of grouse banded on the low-lands and recovered in the sub-alpine. 21 The migration of hens with brood began at the end of July. On July 31, a hen and 3 chicks, much la r g e r and older than a l l sub-alpine broods, were observed. Through August u n t i l snow came i n October, broods continued to pass through the study area although no c l e a r peak was attained, Bendell and E l l i o t t (1967) f e l t that a few broods l e f t the lowlands before the end of August, but most had l e f t by mid-Septem-ber. However, the sub-alpine data c l e a r l y shows that some broods leave both e a r l i e r (August 1) and l a t e r (October 10). Further, on October 31 I was able to locate a hen i n second growth Douglas f i r (Pseudotsuga  menziesii) on the edge of the Comox Burn lowland study ar e a • i n d i c a t i n g that even at that l a t e date some.female grouse remain near the summer range. In migration I found the grouse moved from the lowlands on foot as reported by Lance (1967). They moved alone, i n p a i r s , and i n groups of up to at l e a s t 6 b i r d s . Apparently, d i f f e r e n t age classes of males t r a v e l l e d together as I c o l l e c t e d a y e a r l i n g and an adult from a group of 3 males. At no time were 2 broods seen together. Lone hens were usually alone although they were seen with males (3 times), together (1), and with a hen with brood (1). The grouse apparently moved i n 'waves' which passed through d i f f e r e n t areas on d i f f e r e n t days. Moreover, some parts of the study area were traversed by more grouse than others. High c l i f f s and steep-sided canyons appeared to be b a r r i e r s to movement and tended to funnel the grouse up the easterly ridges and slopes. Figure 4 (page 20) shows canyons and c l i f f s that were d i f f i c u l t to ascend or cross on foot (for me, so I assume grouse a l s o ) ; and the areas where concentrations of 22 grouse appeared. Arrows show direction of travel. (Well-placed d r i f t fences and traps in areas of concentrated movement, such as the top of Beecher and the south slope of Washington, would likely catch a large number of migrating grouse). Migrating grouse were found i n a l l habitats of the sub-alpine although 70 per cent (Table 5) were found i n Parkland and Open Parkland types. This habitat was found on most ridges and upper slopes where TABLE 5 Use of Sub-alpine Habitats by Migrating Grouse (in per cent) Habitat Type (per cent of study area i n brackets) Grouse Class Number Observed Dense and Open Forest (38) Cliff- and Ridgetop (37) Parkland and Open Parkland (25) Males 96 3 20 77 Lone Hens 28 11 25 64 Hens with Brood 39 28 18 54 Total 163 10 20 70 c l i f f s and canyons funnelled the.grouse (Figure 4, page 20) and as a result, i t is d i f f i c u l t to know i f the grouse were selecting i t . Further, the smaller proportion of observations of grouse in dense habitats (forest, C l i f f ) was partly the result of greater d i f f i c u l t y of search. Nevertheless, the.overall distribution of migrating grouse was very different to that of the grouse during the breeding season when none was 23 found i n the f o r e s t , and 76 per cent occurred i n the C l i f f and Ridgetop h a b i t a t s . In migration, the grouse appeared to be choosing a d i r e c t i o n of t r a v e l f i r s t and, secondly, a route that permitted t r a v e l , though not n e c e s s a r i l y the easiest (Lance 1967). In spring migration, 9 grouse and the tracks of about.35 others were recorded. This was - about 20 per cent of grouse observed during the autumn migration. C l e a r l y , many grouse that crossed,the study area i n autumn e i t h e r returned to the lowlands by a d i f f e r e n t route, went undetected, or died between autumn and spring. I t was hypothesized that the d i f f e r e n c e i n numbers observed in,the autumn and spring would represent over-rwinter mortality. However, the great difference i n numbers detected (80 per cent) as opposed to the known annual mortality of about,30 per cent (Zwickel and Bendell 1967a) indicates that the change i n numbers cannot be used to ca l c u l a t e death rates over winter, and suggests many birds went undetected i n spring. In summary, grouse, l i k e most b i r d s , show c l e a r migratory movements to and from where they b reed. They arri v e d on t h e i r breeding grounds over a two-week period i n l a t e March and early A p r i l and l e f t from July through to October. Males and lone hens migrated f i r s t with the peak of t h e i r movement i n August. Hens with brood migrated through August, September, and in t o October. The number of grouse observed i n the spring was much below the number counted i n the autumn suggesting that some bi r d s returned to the breeding ranges undetected, or t r a v e l l e d by d i f f e r e n t routes to those.used i n autumn. Migrating grouse were found i n a l l habitats of the sub-alpine t e r r a i n as they made t h e i r way to and from winter range. They apparently t r a v e l l e d much of t h e i r journey on 24 foot. Males and broodless hens t r a v e l l e d alone or i n small groups while hens with brood t r a v e l l e d as a s i n g l e u n i t . 5, Habitat Selection by Residents The types of habitat selected by grouse during spring and early summer (A p r i l - J u l y ) l a summarized i n Table 6. As a measure of t o t a l use, the data f o r a l l classes of grouse f o r each habitat was summed. TABLE 6 Number of Grouse i n each Sub-alpine Habitat during the Breeding Season ( i n per cent) Habitat Type'and Percentage of To t a l Study Area Grouse-Glass Number Dense Observed- Forest (32) Open Forest (6) C l i f f Ridgetop Parkland (33) (4) (17) Open Parkland (8) Hooting Males 95 72 19 9 S i l e n t Males 53 - 2 30 23 45 -Lone Hens 11 - - 45 18 36 -Hens with Brood 10 - 10 • 10 10 70 -Totals 169 - 1 53 20 26 -C l e a r l y , most grouse selected the open types of habitat ( C l i f f , Ridgetop, and Parkland) i n preference to the heavily forested types and barren 25 mountain uplands (Dense and Open Forest, and Open Parkland). However, there were differences i n how the classes of grouse responded to the habitats and these w i l l be examined below. The d i s t r i b u t i o n of migrating grouse by habitat was very d i f f e r e n t to residents (Table 5,'page 22). In migration, 77 per cent of the males were found i n Parkland types, whereas only 9 per cent of the hooting and 45 per cent of the s i l e n t males were observed i n t h i s h a b i t a t . The 2 difference i s highly s i g n i f i c a n t (Chi =109.6, l d f ) , There was also a 2 s i g n i f i c a n t d i f f e r e n c e i n the use of C l i f f and Ridgetop (Chi =16.1, 3df) with a few migrating males (20 vs. 77 per cent) being found i n these types. Hence, migrating male grouse do not s e l e c t c l i f f edges and other prominences as do residents i n spring and summer, (a) Males Within the three habitat types where hooting males were found ( C l i f f , Ridgetop, and Parkland), there were clear preferences shown. Although the greatest percentage of the hooting males (72) were found i n the C l i f f type, when what was a v a i l a b l e i s considered, Chi-Square 2 tests i n d i c a t e that Ridgetop was more strongly preferred (Chi =13.5, 1 d f ) . Apparently breeding males preferred hooting posts that offered the greatest f i e l d of view and, therefore, more often chose the Ridge-top habitat and, secondly, the C l i f f type. The lack of openings and/or exposed points l i k e l y was the reason hooting males were not found i n the heavily forested h a b i t a t . This does not explain why hooters were not found on the f l a t , open tops of mountains (Open Parkland), a type of habitat occupied on the lowlands (Bendell and E l l i o t t 1967). 26 S i l e n t males observed during the spring selected the same habitat types as the hooting males although on rare occasions (1/53) they were found i n dense f o r e s t . Further, the Ridgetop was the type most highly 2 preferred by them (Chi =36.0, 1 d f ) . But differences i n habitat s e l e c -t i o n between hooting and s i l e n t males did e x i s t . F i r s t , a s i g n i f i c a n t l y 2 smaller (Chi =56,9, 1 df) proportion (30 vs 72 per cent) of s i l e n t males were found i n the C l i f f type. Secondly, there was a s i g n i f i c a n t l y 2 (Chi =806, 1 df) greater proportion (45 vs 9 per cent) of the. s i l e n t males i n Parkland habitat. Hence, s i l e n t males did not appear to s e l e c t open c l i f f edges and prominences as 'hooters' but, instead, l i v e d i n the parkland f o r e s t which was often nearby. Whether some of the s i l e n t males were hooters away from t h e i r song posts when observed, i s unknown. Nevertheless, 65 per cent were within 500 feet of known hooting posts suggesting t h i s may have been the case. Habitat s e l e c t i o n can also be examined by noting where y e a r l i n g grouse and new 'hooters' were found as compared to the d i s t r i b u t i o n of ol d hooters on t e r r i t o r y (Table 7,.page 27). The hooting yearlings were evenly d i s t r i b u t e d i n the three important habitats while 60 per cent of the s i l e n t yearlings were found i n the C l i f f type. On the other hand, the d i s t r i b u t i o n of the 12 new hooters i n 1966 (replacements f o r males shot i n 1965), was very s i m i l a r to that of o r i g i n a l hooters. In summary, these data i n d i c a t e that males e s t a b l i s h i n g song posts s e l e c t the same kinds of habitat as used by old b i r d s . A s i m i l a r observation was made on the lowlands by Bendell and E l l i o t t (1966). However, with-i n the preferred h a b i t a t s , Bendell and E l l i o t t found that resident males 27 TABLE 7 Habitat Selection by New Males and; Yearlings Compared to Old Males (in per cent) Grouse Glass Habitat Type Number Observed C l i f f Ridgetop Parkland Males (1965) 50 62 24 12 New Males (1966) 12 59 25 16 Y e a r l i n g Hooters 6 33 33 33 S i l e n t Yearlings 5 60 20 20 attracted new males to p a r t i c u l a r song posts. This did not appear to be the case i n the sub-alpine as 5 of the 12 replacements (1966) hooted from song posts not used i n 1965 and, secondly, 2 of the other 7 were yearlings that could not have been attracted to a resident male as they hatched a f t e r the residents were shot i n 1965. The data above show that hooting males s e l e c t only parts of the sub-alpine, but did habitat alone explain t h e i r d i s t r i b u t i o n ? The locations of the 46 hooters on Beecher and Washington i n 1965 were plo t t e d along with the habitat types (Figures 5a and 5b, pages 28 and 29) and the Clark and Evans (1954) 'distance to nearest neighbour' test applied. This test involves the c a l c u l a t i o n of R which ranges from 0 (clumping) to 1 (randomness) to 2,1491 (even spacing). For the e n t i r e study area R=l„44, while R=l„62 f o r Washington only and 1.77 for Beecher only. In each.case the test showed a highly s i g n i f i c a n t tendency to-wards even spacing of males despite the obvious e r r a t i c d i s t r i b u t i o n of Figure 5a. Location of male territories and habitat types on Mount Washington. Figure 5b. Location of male territories and habitat types on Mount Beecher. 30 preferred habitat (Figures 5a and 5b, pages 28 and 29) for song posts. The average distance between males was 0.303 miles (1600 f e e t ) . When I calculated the maximum spacing possible with the males evenly d i s t r i b -uted using Clark and Evan's test i n reverse, the males would have been 0.453 miles (2390) feet apart. However, when only that part of the study area i n which they were found i s considered, maximum spacing i s only 0.335 miles (1770 f e e t ) . This suggests males f i r s t selected t h e i r habitat types and, within them, spaced themselves maximally, perhaps through some form of t e r r i t o r i a l behavior. (b) Females Only hens observed i n the sub-alpine from A p r i l through July were considered resident although hens with small chicks were seen i n August. Chicks under f i v e weeks are known to remain close to t h e i r hatch s i t e s (Caswell 1954, Henderson 1960, and Lance 1967). Hens i n the spring and early summer were found i n very d i f f e r e n t habitat to that used by hens i n migration. Seven of the 11 hens ob-served were on steep slopes (30 to 45 degrees) of the C l i f f and Ridgetop types. They were i n areas of very t h i c k , t a l l bush (2 to 8 feet) (Vaccinium, Alnus, Rhododendron, Cladothamnus) containing scattered trees and small rock outcrops. Migrating hens of l a t e summer were never observed i n such h a b i t a t . The remaining 4 hens were i n Parkland although a l l were within 500 feet of thick bush and c l i f f s . These data suggest that hens i n spring seek,these steep bushy areas and, i f so, i t would help to explain why few were observed. Such habitat was the f i r s t to lose i t s snow cover i n the spring and show new vegetative growth. This may have att r a c t e d the hens as a.source of nutrients necessary for 31 egg production. Unfortunately, the crops of hens collected in this period contained no food. Although the hens were found in the same habitats as the silent males, they were not found.;in-the same parts of these habitats. Silent males were rarely found in the extremely dense bush of steep slopes where most females were located. Hooting males were never found in such habitat, although a few were near i t . Eight of the 11 hens were within 150 yards of known hooting posts. With random spacing only 2 or 3 should have been within that range. This supports the observations of Lance (1967) and Bendell and E l l i o t t (1967) oh the lowlands that hens choose areas close to males. Of the 10 hens with brood seen in July, 7 were in Parkland habitat and 9 were in gently sloping areas where red heather (Phyllo-doce), white heather (Cassiope), and low Vaccinium species predomin-ated. The other brood was on a rocky clearing of a low ridge in the Open Forest type where Vaccinium, copperbush, and rhododendron dominated. Tree cover within 100 feet was often less than 5 per cent and always under 20 per cent. In summary, the habitat the broods occupied appeared to be some of the most open habitat available. These observations agree with those of Bauer (1962), Lance (1967), E l l i o t t (1965), and others for blue grouse broods i n other areas. Hens with brood did not appear to select wet areas with succu-lent vegetation as reported by Lance (1967) and Marshall (1946). The weather during the last two weeks of July, when most of these broods were observed, was very hot and dry. Only 2 of the 10 broods were found near water although 3 others were i n damp areas. The other 5 were i n dry locations with 2 of them at l e a s t 2000 feet from e i t h e r water or damp ground. I t i s probable that the food^chicks (see Appendix E) along with lower temperatures permitted more independence from free water than found on the lowlands (Lance 1967). The data on hens wane i n s u f f i c i e n t f o r any analysis of s p a t i a l r e l a t i o n s h i p s between hens or differences between adult and yearlings i n choice of habitat. Moreover, only 1 nest was found. Hens with brood (7) found i n July were widely scattered, which may i n d i c a t e spac-ing . More data are needed. (c) Winter Grouse.and grouse sign were.rarely seen i n the winter except i n the open fo r e s t (Parkland and Ridgetop habitats) of higher elevations. This habitat was very d i f f e r e n t to the same habitat i n spring and summer, as a l l ground vegetation and rock outcrops were hidden by a blanket of snow (Figure 20, page.97). And as the winter progressed, the snow increased (to 18 feet i n March, 1966) to e f f e c t i v e l y bury a l l trees under 25 feet. This reduced crown cover by about h a l f i n a l l parts of the parkland not dominated by very.large trees. Further, young trees and trees with narrow crowns (Abies l a s i o c a r p a ) , even i f not buried, became snow bound to such an extent no limbs or f o l i a g e re-mained exposed (Figure 23, page 97). Within the parkland i n winter, the grouse were not evenly d i s -t r i b u t e d . The presence of large trees appeared important as few birds 33 or sign were found where only young trees grew. Apparently the large trees not only allowed grouse to move e a s i l y i n them and get food (needles, see Appendix E), but offered p rotection from the weather. Dense scrubby trees on exposed ridges were used but mainly i n periods of calm weather. Parkland having large trees was r e s t r i c t e d to about one-half square mile on the main peak of Beecher and to about 1 square mile on Washington. Through the winter of 1965-66 between 10 and 15 grouse l i v e d on the study area. A l l birds observed were males of which 4 (shot) were adult and the others believed to be. A l l hens and chicks disappeared from the study area with the f i r s t snow i n mid-October and none was observed again u n t i l l a t e March., Through the winter, extensive search i n a l l parts of the study area, i n adjacent areas, and i n lowland f o r e s t , f a i l e d to discover e i t h e r hens or j u v e n i l e s . Males, however, were seen r e g u l a r l y i n a l l parkland areas v i s i t e d , not only on Vancouver Island (Mount Arrowsmith and Wolf Mountain), but also i n i n t e r i o r B r i t i s h Columbia (Apex Mountain). In summary, these observations suggest that at l e a s t a portion of the male population u t i l i z e d a d i f f e r e n t winter range than that used by hens and j u v e n i l e s . The sexes winter separately i n ptarmigan (Lagopus mutus and L_. lagopus) (Weeden 1964) and c a p e r c a i l l i e (Tetrao urogallus) (Sei s k a r i 1962), so i t would not be unique to blue grouse amongst tetraonids. Observations of blue grouse, i n winter by Skinner (1927), Marshall (1946), and Caswell (1954) support t h i s conclusion. Whether the grouse found i n winter were the same or d i f f e r e n t , to those which bred on the study area was not p o s i t i v e l y known. A l l 34 males were shot i n 1965 where they were found i n winter (1965-66) but they may have moved from peripheral parts of the study area. I do not think the males found hooting i n the,spring of 1966 were those which wintered on the area because they were much below winter males i n weight. In early winter (November-January) grouse.were seen alone, i n small groups (2 to 3), and on one occasion (Apex Mountain) i n a f l o c k of 12.to 15. A f t e r mid-January a l l grouse seen were alone and may even have been spaced. Four males remained 100 to 150 yards apart on a small area of Beecher f o r at l e a s t 6 weeks i n February and March. S t i r l i n g (1965) observed aggressive behavior and hooting amongst.males i n January and February i n the aviary at The U n i v e r s i t y of B r i t i s h Columbia, My observations on the males i n January and February may, have represented S t i r l i n g ' s aggressive behavior, although,I observed neither f i g h t i n g nor hooting. While some grouse spent long periods (to at l e a s t 8 weeks) i n one.tree,or a clump of trees, others evidently moved about a large area as old sign . (tracks, droppings) was occasionally found where grouse were not.. Most grouse observed were i n trees feeding or l o a f -ing (at which they spent long.periods of time), But grouse did walk on and roost i n holes i n the snow. Most ground roosts were i n powder snow away from trees, and appeared to have been entered from f l i g h t . Most snow roosts, were used for only one night (18 to 24 droppings), however, large numbers of droppings (over 100) suggested some were used f o r two or more nights (and days?). 35 Blue grouse do not develop the large comb-like fringes on the toes as found i n ruff e d grouse (Bonasa umbellus) (Bump et a l . , 1947) although l a t e r a l fringes of e l a s t i c horny rods (present a l l year) do enlarge s l i g h t l y . When the snow was very s o f t , I observed grouse walking on the feathered tarsus i n a slow and awkward s h u f f l i n g step. The r e l a t i o n s h i p of body weight to the surface area of the feet of adult males i s about 80 gms/sq. cm. When the surface area of the tarsus i s also considered, the r a t i o i s reduced to about 40 gms/sq. cm. This r a t i o i s comparable to that of r u f f e d grouse (35 gms/sq. cm.) and partridge (Perdix perdix) (48 gms/sq. cm.) for the feet only (Wester-kov 1965). These observations suggest that blue grouse are not as highly adapted for walking i n s o f t snow as some Galliformes, and may explain why they spend much of the time i n trees i n winter. To summarize, blue grouse i n the sub-alpine i n both summer and winter pre f e r open habitat ( C l i f f , Ridgetop, and Parkland types) to the heavily forested areas (Open and Dense Forest types) and barren mountain tops (Open Parkland). In spring, displaying males selected ridgetops and c l i f f edges for t h e i r song posts. S i l e n t males during spring selected the same kinds of habitat as did the displaying males, although more were found i n parkland forest away from prominences and openings. In spring, hens appeared to s e l e c t t h i c k bushy areas of the c l i f f habitat while hens with brood i n July selected very open habitat with short vegetation. In winter, a portion (or a l l ? ) of the male grouse wintered separately from.the hens and juveniles and these birds selected the Parkland habitat dominated by large old trees. In l a t e winter these males may have been spaced apart through some form of i n t r a s p e c i f i c behavior. In general, the s e l e c t i o n of habitat was s i m i l a r to that reported for grouse on lowland breeding ranges. 36 6. Reproduction Hooting display, the t e s t i c u l a r cycle, and peak of hatch were examined along with snow pack, temperature, and date. These were then compared to sim i l a r observations made on the nearby lowland ranges (Figure 6, page 37). Data for the lowlands were taken from several sources (Bendell 1954, Zwickel 1965, Simard 1964, Stewart 1967, and unpublished data). Clearly, a l l events of the breeding season i n the sub-alpine following the a r r i v a l of grouse to areas where they bred were s i g n i f i -cantly delayed. I t i s also clear that the delay occurred i n the early part of the breeding season, that i s , i n the period before the testes reached the i r peak development and egg laying began. As the primary causes of the delay was apparently the sub-alpine weather of A p r i l and May, this i s examined before going into the s p e c i f i c events of the breeding season. (a) Influence of Weather The weather was much colder i n the sub-alpine with average maximum temperatures 22 degrees cooler and minimums 12 degrees cooler than on the lowlands i n the same week (Figure 7, page 38). In the sub-alpine, sub-freezing temperatures were common i n A p r i l and May and snow storms occasionally occurred. In May 1965 and 1966 (this was the only month i n which data were collected i n both years), average maximum temperatures were i d e n t i c a l , although minimums averaged 2.5 degrees lower i n 1966. Probably the most important effects of the lower temper-atures were that they retarded the disappearance of the winter snow pack - I I L_ I I I I I I | I I I | 1 1 1 A P R I L MAY JUNE JULY M O N T H Figure 6. A comparison of the timing of some events of the breeding season between the sub-alpine and lowlands. I 80+ LLI (X D h < 60-(X hi CL UJ AO-I -20- m I 9 16 24 M A Y 1 9 6 5 MEAN T E M P E R A T U R E S MAXIMUM LOWLANDS SUB-ALPINE • MINIMUM • MAXIMUM - MINIMUM H r 9 16 24 1 9 16 A P R I L M A Y 1 9 6 6 f — f 24 Figure 7. A comparison of spring temperatures between the sub-alpine and the lowlands in 1965 and 1966. Weekly mean maximum and minimum temperatures are shown* 39 and prevented ground vegetation from resuming growth; By A p r i l 1 i n both years, the lowlands were free of snow,and by mid-April new vegetative growth was w e l l underway. The snow pack of the winter of 1964-65 was le s s than that of 1965-66 and melted sooner.. The f i r s t areas from which snow melted were,the c l i f f edges with southerly exposures and windswept ridgetops. As l a t e as June 1 in,1966 few other,areas were free of snow and leaves were only.just,beginning to appear. In 1965.by June 1, areas with sprouting shrubs.were exposed on a l l slopes. However, as w i l l be noted l a t e r , breeding was n o t . e a r l i e r i n 1965 as might.have,been ex-pected had snow cover and new growth been important. Apparently, temperature alone may suppress breeding of b i r d s (Lofts and Murton 1968). These authors say temperature has a d i r e c t e f f e c t which ,acts, independently of vegetative growth and the supply of food.' (b) Hooting Display The f i r s t conspicuous event i n the breeding ,cycle i s the i n i t i a -t i o n of song. Figure 6 (page.37) showed that hooting began l a t e r and took longer to reach i t s peak i n the sub-alpine than on the lowlands. Figure,8 (page 40) compares i n greater d e t a i l . t h e hooting of males of the sub-alpine with that given by Bendell (1956) f o r low elevation: breeding populations of Vancouver Island. The units used to measure hooting were d i f f e r e n t but the r e s u l t s are, nevertheless, comparable. In the sub-alpine hooting was-measured by counting the number of hooters heard per week and by noting how many were heard at a given time. In 1966, hooting was f i r s t heard on A p r i l 24, a day that was stormy with f a l l i n g snow. The b i r d was.in a tree on a slope where snow • • SUB-ALPINE • • LOWLANDS APRIL MAY J U N E JULY AUGUST M O N T H Figure 8. Seasonal change in hooting males through the summer in fcHe sub-alpine and on the lowlands. The numbers represent sub-alpine sample sizes. 41 lay 8 to 10 feet deep. Its hooting was frequently broken.by 2 or 3 minutes of silence and after 15 minutes, i t stopped completely. Similar sporadic hooting continued through the last week of April and f i r s t two weeks of May. Of 16 males heard in this period, 11 were known to have hooted from trees where snow lay unbroken on the ground. No bird was ever, seen to hoot while on snow, although 4 were heard to hoot during snow storms. It was May 12 before continuous hooting for a , f u l l hour, from a single bird was heard. Hooting was most widespread in the last week of May in both years when 90 per cent (Figure 8, page 40) of a l l males observed (54) were hooting. The increase in activity was reflected in the number,of males collected (equal effort) in the 10 days before and after May 18 (Table 8). TABLE 8 . Number of Grouse Collected in the 10 days before and after May 18 in 1965. and 1966 Grouse Collected Year Before May,18 After May 18 1965 2 12 1966 3 12 Totals 5 24 Grouse hooted long enough after that date to allow time to find them. The difference between the numbers shot before and after May 18 is highly significant (Chi2=13.9, 1 df) „ 42 In June, the.number of hooting males f e l l rapidly. . At the begin-ning of July there was a very noticeable second peak in hooting activity which lasted until July 13. After that date, hooting was heard on only 4 days with the last on August 22. The peak in early July was correlated with the period of hatch in the sub-alpine (page 49) and may have resulted from the sudden appearance of hens (with brood) stimulating males to hoot. Bendell (pers. comm.) says that a similar secondary peak in hooting activity may occur on the lowlands. It i s apparent from Figure 8 (page 41) that the peak display on the.sub-alpine came about 3 weeks later than that reported for the low elevations (Bendell 1955b). Also, a high level of display was maintained for less than a month versus 2 months on the nearby lowlands. Further, hooting ceased on the uplands about the same time as on the nearby low-lands. As w i l l be seen in the next section a similar relationship was found in the testicular cycles of the high and lowland populations. Through the spring (1965 and 1966 combined) 13 yearling males were shot, of which 6 were hooting at the time of collection (Table 9). TABLE 9 The Dates when Yearling Hooters were Collected Date Number Per cent Observed Hooting Before May 18. 2 0 May 18 to June 2 6 83 After June 2 5 20 43 Five of the 6 hooters were c o l l e c t e d between May 20 and June 2 and the s i x t h on June 25. On the lowlands Bendell and E l l i o t t (1967) c o l l e c t e d 16 hooting yearlings of which 63 per cent were observed i n the two-week period of A p r i l 26 to May 11 with the remainder ( a l l replacements,for shot males) scattered through May, June, and J u l y . When these data f o r the sub-alpine and lowlands are compared to the curves i n Figure 8, (page 40), i t i s apparent that most yearlings i n both populations hooted only during the peak of dis p l a y . ' When hooting began, temperatures i n the sub-alpine averaged 32 degrees, that i s , 13 degrees lower than when hooting began on the low-lands (Figure 7, page 38). And when the peak was reached, average temperatures were 20 degrees lower than on the lowlands. Temperatures i n the sub-alpine did not reach those.found i n A p r i l on the lowlands (when lowland hooting reached a peak) u n t i l l a t e June, that i s , a f t e r hooting i n the sub-alpine had begun to subside. Hence, although the sub-alpine temperatures apparently delayed hooting, hooting c l e a r l y did not.depend on,a f i x e d temperature for i t s i n i t i a t i o n or maximum l e v e l of i n t e n s i t y , (c) T e s t i c u l a r Cycle To substantiate and explain the delay i n the peak of display a c t i v i t i e s i n the sub-alpine, the change i n s i z e of the testes was studied. Song i s a secondary sex c h a r a c t e r i s t i c and i t s i n t e n s i t y has been shown to be d i r e c t l y r e l a t e d to the s i z e of testes ( C o l l i a s and Taber 1951, Johnston 1956, Simard 1964). Figure 6 (page 37) showed that maximum-development of the testes and the peak.of display a c t i v i t i e s 44 did,coincide. To study the t e s t i c u l a r cycle in.the sub-alpine i n greater d e t a i l , 75 pai r s of adult and 19 pair s of y e a r l i n g testes were measured vo l u m e t r i c a l l y . The volumes f o r each week were averaged and plo t t e d and a running average drawn f or adults and yearlings (Figure 9, page 45), A l l grouse c o l l e c t e d i n 1965 and 1966, bo t h , s i l e n t and hooting, were pooled into one year as samples were too small to te s t separately. Only i n the t h i r d week of .May were the samples of adult males f o r 1965 (7) and 1966 (5) large enough to compare f or differe n c e between years. The average s i z e of testes were i d e n t i c a l (1.11 vs. 1.12 cc.) which suggests that there was no differe n c e between years i n the rhythm of the reproductive cycle. In no week were the samples of bo t h . s i l e n t and d i s p l a y i n g males adequate f o r comparison. Simard (1964) found no differe n c e between s i l e n t and hooting males on the lowlands. By inspection of Figure 9 (page 45), there :.are c l e a r l y some s i m i l a r i t i e s and some differences between the t e s t i c u l a r cycles of the sub-alpine and lowlands, The points i n common between adult and y e a r l i n g of high and low elevations are the date of commencement of recrudescencei the rate (slope) of f i n a l regression and the t o t a l length.of the cycle. That these p a r t i c u l a r points are s i m i l a r , strongly suggests that the same mechanism is.operating to con t r o l them. It w i l l also be noticed that the maximum s i z e attained by adults and yearl i n g s , coincides within t h e i r respective summer range, Differences i n the t e s t i c u l a r cycle between.the sub-alpine and lowland grouse with p a r t i c u l a r r e f e r e n c e : t o the adults were the following: 0) LU ul (/) . LU • h CN o > LU CD < tr. Ll • -o • -o CN • -o W E E K L Y AVERAGES • A D U L T • Y E A R L I N G RUNNING WEEKLY AVERAGES S U B - A L P I N E L O W L A N D S • A D U L T • YEARL ING ' • L -l u MAR APR Figure 9-MAY J U N E JULY AUG S E P T M O N T H Seasonal variation in average volume of the testes of adults and yearlings of the sub-alpine compared with the lowlands (see appendix N for sample sizes). 46 f i r s t , recrudescence took approximately 10 weeks in the sub-alpine versus 6 in the lowlands. This difference of 4 weeks is approximately the time lapse between a l l subsequent events of the breeding season between the grouse at the different elevations. Second, the maximum testes size which was reached during the last week of May and f i r s t week of June was not followed by a prolonged plateau with slow regression. Rather, regression in size began almost immediately and proceeded at the same rate found in the later stages of lowland grouse. Third, the maximum weekly average testicular volume was 1.55 cc vs. 2.09 cc on the lowlands and the average sizes for the peak 2 weeks were 1.43 cc (9) vs. 1.90 cc. (10). They were s t a t i s t i c a l l y different. When these volumes were related to average body weights (1246 grams vs. 1306 grams), testes in the sub-alpine grouse were s t i l l 27 per cent smaller. The largest sub-alpine pair of testes had a volume of 2.30 cc. versus 3.60 cc. on the lowlands. Simard (1964) found nine grouse with testes over 2.30 cc. and 15 others larger than the second largest pair (1.75 c c ) . The cause of the greater number of large testes and greater size in relation to body weight on the lowlands was likely the difference in temperature between the high and low elevations. Temperature causes differences in testicular size in other species of birds (Burger 1948, Lofts and Murton 1968). Lastly, regression was delayed one week compared to that on the lowlands. A study of the moult pattern of primary feathers suggested a similar delay compared to lowland males (Appendix F). In yearling males there does not appear to be any difference in size of testes between the lowlands and sub-alpine as found in adults. The high peak (June 1) in yearlings from the sub-alpine is based on a sample of only one b i r d . This i s quite inadequate f o r ei t h e r comparison with the lowlands or generalizations. Compared to the lowlands, i t i s cl e a r that the average maximum s i z e of the testes of-yearlings i n the sub-alpine was lower.if the si n g l e b i r d shot i n ' l a t e May i s not considered. As found by Simard (1964), recrudescence i n the yearlings was much slower than i n adults. S i m i l a r l y , no t e s t i c u l a r volume of a ye a r l i n g was found to overlap that of adults of the same week. In summary, both,the slow recrudescence and smaller s i z e of, sub-alpine testes can be, at t r i b u t e d to the lower temperatures. • More-over, because of the slow recrudescence, the length of season when v i a b l e sperm was produced was. reduced from 9 weeks to about 6 weeks (Simard 1964). This d i f f e r e n c e i n length of the e f f e c t i v e male cycle, one would expect, should b e , r e f l e c t e d i n the length of the period of hatch. This w i l l be considered i n the section on female reproduction to follow. (d) Females My data on breeding by females dv_e, at best, fragmentary (Appen-dix G) . The only nest located i n the sub-alpine was that of an adult hen with a clutch of.5 eggs found on July,13, 1965„ And even t h i s nest may have been a renest as i t was,2 weeks behind the average date f o r nests (below). (The hen defended the nest by vigorously attacking the,dog. Apparently t h i s i s unusual as Bendell and E l l i o t t (1967) state that a f t e r observations of many nest hens, that hens, when disturbed from 48 t h e i r nests e i t h e r f l u s h , or jump erect and walk away,without any p a r t i c u l a r display)„ The embryos were examined and were judged to be, 10 to 12 days of age on the basis of embryo growth i n pheasants; as given by Roseberry and Klimstra (1965). On June 9, a s i n g l e egg was found laying on bare ground under, a tree. There was no attempt to b u i l d a nest and a f t e r 5 days the egg was c o l l e c t e d . I t was.probably a 'dumped' egg. The only other evidence of nesting was from an adult hen shot May 28, 1966, at 4500 feet. I t had enlarged f o l l i c l e s (largest was 20 mm i n diameter) and possibly would have been l a y i n g w i t h i n a week. As only 1 nest was found, sub-alpine hatch dates were determined from the ages of chicks,located i n d a i l y search. Chicks were aged using the growth and moult of primary feathers (Zwickel and Lance 1966) and s i z e and behavior (Smith and Buss 1963). The estimated date of hatch f o r 7 broods observed i n July, the incubating hen, and a dead chick, are shown i n Figure 10, page 49, Hatching took place throughout,the month of July with the peak about July 10 (Figure 10). The e a r l i e s t date was about July 4, and the l a t e s t July 28 (had the neS.t hatched). On the lowlands, the peak of hatch i n 1965 was about.June 16 (unpublished data) and extended over 5 weeks from June,11 to J u l y 12, C l e a r l y , the peak of hatch on the sub-alpine was 3 to 4 weeks behind the lowlands and, therefore, agrees with the, difference i n peaks of t e s t i c u l a r cycles already shown-. Hatch on the lowlands (Zwickel 1965) extends over 9 weeks (June 1 to August 1). The shorter breeding season of the sub-alpine may mean that fewer hens that l o s e . f i r s t clutches renest, which account,for 24 per cent.of the successful lowland broods,(Zwickel 1965). L O W L A N D S \\ \ ' . S U B - A L P I N E J U N E J U L Y W E E K F i g u r e 10. A comparison of sub-alpine and lowland hatch dates f o r 1965 50 During May and.June, I c o l l e c t e d 3 y e a r l i n g females; none.showed ovarian development. I t was most u n l i k e l y that the two c o l l e c t e d i n . June would have nested as t h e i r eggs ( i f l a i d ) would not have hatched before the l a s t week of July; l a t e even f o r the sub-alpine. Also, both showed advanced stages of primary feather moult, which i n breeding hens does not begin u n t i l a f t e r hatch (Boag 1965 and Appendix F) «, Of the 7 hens_seen.with broods during July, none was i d e n t i f i e d as,a y e a r l i n g although three were adults. In summary, I conclude that sub-alpine y e a r l i n g hens do not breed. This i s also the case i n southwest Alberta (Boag 1966). On the lowlands, however, y e a r l i n g females make up 36 per cent of the breeding population of hens,(Zwickel ,1965). This could be an important f a c t o r i n the population dynamics of grouse. (e) Brood Size and Growth The data on brood s i z e were divided,into those f o r July, August, and September-October (Table 10). The July data contains only broods TABLE 10 Average Brood.Size i n the Sub-Alpine and Lowlands i n 1965 Sub-•alpine Lowlands Month Number Observed Average Brood Size Number Observed Average Brood Size July 7 3 d 7 - -August, 13 3.38 47 3.12 Sept.-Oct. 13 2.61 - -Source: Unpublished data f o r Comox Burn, 51 resident in,the highlands while those for August through October are l a r g e l y migrants from the lowland,- The lowland data were c o l l e c t e d between July 15 and August 5, 1965. The number of sub-alpine broods recorded i n July was i n s u f f i c i e n t to generalize on average brood,size. Also, i t i s l i k e l y that not a l l chicks.were counted i n some of the very young broods where the chicks h i d in.the vegetation rather than f l u s h i n g . A comparison of brood s i z e i n August and l a t e r , i s e s s e n t i a l l y a comparison of lowland broods s t i l l on the .lowlands with others which have begun migration. The difference i n s i z e between lowland and sub- . alpine broods in :August was n o t , s i g n i f i c a n t . . There was, however, a s i g n i f i c a n t difference between the mean s i z e of broods seen i n August and,those of September-October i n the sub-alpine.. Hence, there was l i t t l e . l o s s of chicks i n t h e i r movement to the sub-alpine, but there was e i t h e r a loss of chicks a f t e r they reached the sub-alpine or some broods s p l i t up. I observed l i t t l e evidence of chick mortality (one caught by a hawk) or of broods s p l i t t i n g (only 4 lone,chicks were seen). As broods,hatch much l a t e r i n the sub-alpine than on the low-lands ,, they may grow f a s t e r i n the sub-alpine to compensate.for t h i s . The weights of chicks c o l l e c t e d were compared with data growth given by Bendell (1955c) and with unpublished lowland data. Weights of chicks were f i r s t p l o t t e d against those from the lowlands according to date of observation (Figure 11, page 52)„ C l e a r l y , when lowland chicks were 5 weeks old and weighed 2 to 300 grams, the average sub-alpine chick was 2 weeks and weighed only 60 grams. Sub-alpine chicks did not,reach 300 grams u n t i l l a t e August when those from the lowlands weighed twice as much. 700--600--500-• 400 X O 300-U 200 — 100--JUNE JULY AUGUST S E PTE M BE R M O N T H Figure 11. A comparison oi" the growth of chicks i n the sub-alpine and on the lowlands. The s o l i d dots are weights of sub-alpine chicks and the s o l i d l i n e s are the 95 % confidence l i m i t s of chick weights on the lowlands. The lowland confidence l i m i t s are also shown super-imposed on the sub-alpine weights (dotted l i n e s ) with sub-alpine and lowland hatch dates synchronized. 53 When hatch dates were synchronized, a l l weights of sub-alpine chicks fell.within the confidence limits of lowland chick weights of the same chronological,age. Unfortunately, I have no data on September chicks to show whether growth accelerated i n autumn. The weights of yearlings collected in spring suggest that the chicks do not,accelerate growth in autumn. Twelve yearling males averaged 995±;141 grams (t.05) versus 1110± 40 grams for 8 from the lowlands (Bendell 1955c), Eleven of the 12 were under ,1035 grams, the lowest lowland weight. Weights of 39 lowland yearling males given by Simard (1964) averaged 1139 grams with only.4 under 1035 grams. Further, the weights of.2 of 4,yearling females (719 and 594 grams, respectively) were also much below those of 11 yearlings (790± 10 grams) collected by Bendell. Moreover, these 2 females did not nest (page 50). Male grouse, at least, may never attain the weights reached on the subT-alpines, as 41 males from April-June averaged 1219 grams versus 1278 grams for 116 from the lowlands for the same months. The range of weights in the high and,low elevation adult males are compared in Figure 12, (page 54). It is clear that fewer sub-alpine males exceeded 1300 grams (24 per cent vs. 38 per cent) while more (37 per cent vs.> 18 per cent) weighed less than 1200 grams. On the other hand, at both elevations'the same per,cent.of males were between 1200 and 1300 grams. It i s possible the sub-alpine grouse did not-reach maximum adult weight until three or four years old. Also, the sub-alpine grouse could be of a different genotype with a lower potential, for maximum weight, but evidence is inconclusive. More males exceeded 1350 grams (19 per cent • o CO LL 0 Z o I d " u a: hi _ o • Q_ -Figure 12, • • • • * • • • . » , * • • • « # • • < n o o / X / ] L O W L A N D S • ^ - ^ h i 6 ) • • • • . • , (11 ) S U B - A L PI N E ( 4 i ; 1101—1200 1201-1300 1301-1400 W E I G H T - G M S V > 1400 A comparison of the range of body weights of adult males from the sub-alpine and lowlands. 55 vs. 10 per cent) on the lowlands, although only one lowland weight exceeded the heaviest sub-alpine b i r d . To summarize,, the reproductive cycle i n the sub-alpine was shorter by 3 weeks and approximately 1 month behind that on the low-lands due, apparently, to the e f f e c t s of lower temperatures. The delay occurred during the period of gonadal recrudescence and res u l t e d i n a slow rate of development of courtship a c t i v i t i e s . Hooting display and t e s t i c u l a r s i z e reached t h e i r maximum in,the l a s t week of May and f i r s t days of June when mating occurred. Yearling females did not breed. Peak of hatch occurred about. July 10, 3 to 4 weeks l a t e r than on,the lowlands; and the t o t a l length of the hatch period was,shorter than on the lowlands, Average s i z e of young broods was,the same i n the sub-alpine as .on the lowlands. However, there appeared to be ei t h e r a loss of chicks or a breakdown of broods as autumn migration progressed. Sub-alpine chicks did not,show accelerated growth to compensate f o r t h e i r l a t e hatch and i t appears l i k e l y , t h a t sub-alpine grouse take longer to reach the adult weight attained on the lowlands. 7. Populations (a) Males The easiest .segment of the grouse population to study were the males, and best data on numbers were .collected on them. In 1965, there, were 46± 1 hooting males on Beecher and Washington which had a combined area of 8,2 square miles (5280 acres). Table 11 (page 56) shows the number of male.grouse per 100 acres for the total area and for the habitat in which hooters were found. Densities on lowland study areas are shown for comparison.1 Clearly, the density of hooting males in. the sub-alpine was. much lower than on a l l lowland areas, although in the preferred Ridgetop habitat, numbers did equal that on Comox Burn. The density on Washington and Beecher.differ slightly but not statis-t i c a l l y . * TABLE 11 Density of Grouse in,the Sub-alpine and on the Lowlands Area Number of Hooters Hooters per 100 acres . Total study area 5360 46 0.87 Washington area 1660 16 0.96 Beecher area 3700 30 0.81 Used part of the study area 2750 46 1.67 -Ridgetop 240 12 5.00 - C l i f f 1505 27 1.79 -Parkland 1005 7 0.70 Lower Quinsam Lake - 38-42 Middle Quinsam Lake - 14-16 Comox Burn — — 5 Source: Lowland data from Zwickel (1965) and Bendell and E l l i o t t (1967). *0n June 6 and 7, 1970, I revisited Mount,Washington to make a census of hooting males. Weather conditions were ideal for this and I believe virtually a l l males were found i n the area searched. I found 8 hooters where 9 had lived in,1965. In addition, one hen was seen. Four of the males were.in Parkland and 4 on Ridgetops versus 3 and 6 in 1965. Over the entire study area, the distance to the nearest neighbour among hooting males varied from 260 to 3000 feet with a,mean of 1600 feet (Appendix I). This compares with 290 feet on the lowlands at Middle Quinsam Lake (Bendell and E l l i o t t 1967). If i t is assumed many areas, empty of grouse, offer suitable l i v i n g space, i t i s obvious that the sub-alpine was grossly under-populated. Possible reasons for the low density of grouse w i l l be considered in the "Discussion" section. In 1965, 1 of the 32 (3 per cent) original hooters collected was a yearling. If the data for Browns Mountain (4 adults, 1 yearling) for 1966 are added, we get 2 yearlings among.37 known aged t e r r i t o r i a l males, that i s , 5 per cent. This percentage of hooting yearlings i n the sub-alpine i s comparable to that found on,different lowland study areas (1 to 9 per cent) (Bendell,and E l l i o t t 1967, also unpublished data). In the sub-alpine in 1965, 4 males (1 :adult, 3 yearlings) re-placed shot hooters (12 per cent) of which 2 may not.have been true-replacements. The adult male was silent when collected about,100 yards , from a hooting adult (collected). Only 1 hooter was known , to l i v e i n the area. And 1 of the 3 yearlings was collected where an adult was shot 8 weeks earlier. Also,.it was silent. The other 2 yearlings were replacements for the same adult collected May 18 which had occupied a prime ridgetop hooting post. The f i r s t appeared 3 days after the adult was shot and the second on June 25,,38 days later. Both were hooting in muffled tones when found. In summary, the replacement rate within the year.was possibly only 6 per cent (2/32). whether 6 or 12 58 per cent, replacement was much below the 43.per cent found on the lowlands ( E l l i o t t 1965), These r e s u l t s suggest there were eit h e r fewer yearlings present i n the sub-alpine, or the yearlings were not capable of hooting because of immaturity or other reasons. In 1966,,12 hooting males replaced the 32 shot i n 1965 f o r a, replacement rate of 38 per cent between years. This was about the rate necessary to take care of the 'normal' annual adult m o r t a l i t y , assuming t h i s mortality to be,the same as on the lowlands (30 per cent) (Bendell and E l l i o t t 1967). Seven of the 12 were c o l l e c t e d , of which 5 were adults and 2 were ye a r l i n g s . The 5 adults deserve further exam-i n a t i o n . Four of the 5 averaged 1108 grams (1020 to 1180) which was 160 grams below the average of 16 other adults from the same period.. Moreover, these 4 possessed very small testes. When t h e i r testes were re l a t e d to ;body weight, they averaged 20 per cent.smaller than those, of the other males. Simard (1964) found that the,testes of,lowland 2-year-old males also averaged less i n s i z e (19 per cent) than those.of older adults, I suggest that these four replacements were 2-year-old birds hooting fo r t h e i r f i r s t season. The f i f t h adult replacement weighed.1313 grams and possessed large testes (1.75 cc.) suggesting that i t was a b i r d that went unrecorded,in 1965. It i s d i f f i c u l t to compare the sub-alpine data f or replacement, between years with s i m i l a r data c o l l e c t e d on the lowlands (Bendell and E l l i o t t 1967). These authors found that over 4 years (1959 to 1962) 21 t e r r i t o r i e s emptied i n one year were replaced i n following years by 59 26 t e r r i t o r i a l (hooting) males (14 adults, 5 y e a r l i n g s , 7 unknown) for a replacement rate of 124 per cent. These data suggest that there were three times (124: 38) as many 2-year-old and y e a r l i n g males a v a i l -able on the lowlands as on the sub-alpine to f i l l empty habitat. How-ever, as Bendell and E l l i o t t were working on a , r e l a t i v e l y small area (2000 x 2000 feet vs. 8.2 square miles), the empty habitat created by shooting t e r r i t o r y holders may have drawn i n y e a r l i n g and 2-year-old males from adjacent areas. This could account for the great difference i n replacement rates, between high and low elevation. It was not possible-to get the absolute number of y e a r l i n g males i n the sub-alpine breeding population as 14 of the 1965 hooters and 5 of the 1966 replacements were not c o l l e c t e d . However, a minimum estimate of the number of yearlings i n the 1965 male population can be made i f i t i s assumed that the 4 small males shot i n 1966 were 2-year-old grouse; and secondly, that these 2-year-old grouse suffered a mortality rate of about 30 per cent i n t h e i r second year, as was found on the lowlands (Zwickel and Bendell 1967). Then the number of y e a r l i n g s . i n 1965 i s the sum of: the.6 c o l l e c t e d during the spring of 1965 . . . . 6 the four two-year-olds . . . . . . . . . . . . .4 and the second year mortality of the two-year olds (30 per cent of x i 4) .2 The sum, 12, works out to 28 per cent (12/32.+ 12) of the sub-alpine population c o l l e c t e d . This was the same proportion of yearlings as 60 reported i n the male population of Comox Burn by Zwickel and Bendell (1967) and only 8 per cent less than reported f o r Middle Quinsam Lake by Bendell and E l l i o t t (1967). I suggest, therefore^ that the number of yearlings i n both the sub-alpine and lowland populations was the same.' The between year replacement rate of .38 per cent appears to support t h i s conclusion. I t follows that - the low replacement within the ..year..(6 to .12 per cent) compared to.the lowlands was more l i k e l y the r e s u l t of the birds being p h y s i o l o g i c a l l y unable to take t e r r i t o r y rather than a lack of grouse.. (b) Females The data I c o l l e c t e d on the female breeding population i n the sub-alpine was, inadequate to permit any conclusions on the. numbers of females, t h e i r density, or age structure. Neverthelessj of the 9 resident females aged, 6 were adults and 3 were yearlings giving a r a t i o (67:33) which was very s i m i l a r to that calculated f o r males (72:28). (c) Production Data.collected pn production and,recruitment were also inadequate for conclusions.. Table 10 (page 50) showed an average brood s i z e of 3.17 chicks for 7 resident broods between,10 and 18 days of age. That 2 of these broods had 6 chicks and,the nest found contained 5 eggs, gives no reason to suppose that clutch s i z e i n the,sub-alpine was d i f f e r e n t from that on,the lowlands., Of more importance,to production and recruitment, was the lack of breeding by y e a r l i n g hens. On the lowlands,,Zwickel and Bendell (1967a) found that y e a r l i n g hens produce about 20 per cent of the successful broods.' I f no y e a r l i n g hens produce chicks i n the sub-alpine then the adults must produce a l l chicks necessary to replace annual mort a l i t y . The adults could do t h i s i f 65 per cent, rather than 50 per cent (Zwickel and Bendell 1967a) of them s u c c e s s f u l l y r a i s e d a brood, or i f chick mortality was 25 per cent lower than found on,the lowlands. Immigration from other.areas could also occur, although none,was recorded.. In summary, i t may be concluded from the data that the sub-, alpine grouse population was sustaining and apparently stable; Remarkably, the parameters of population,.aside from low density, were s i m i l a r to. those found f o r populations studied on the nearby lowlands. (d) M o r t a l i t y Factors Some evidence of mortality through predatipn, parasitism, and disease was obtained.. These f a c t o r s , however, taken i n d i v i d u a l l y or together, did not account for the 30 per cent annual adult,mortality of the breeding population, or- the mortality of chicks oyer winter. In the sub-alpine the main predator of grouse appears to be the goshawk ( A c c i p i t e r g e n t i l i s ) although•cougar ( F e l i s concolor), bear (Ursus americanus), pine marten,(Martes americana), and the. horned,own (Bubo virginianus) may take an occasional grouse. Attacks by hawks.and cougar were observed (Appendix K) and the remains of two k i l l s apparently by an avian predator were found. Almost a l l grouse shot were examined f o r endoparasites. In only 3 yearlings (13 per cent) and 5 adults (6 per cent) were any found (Appendix L) , These included ascarids (Ascaridia bonasae) i n 4 grouse, gizzard worms (Cheilospirura spinosa) i n 1, and tapeworms (Rhabdometra n u l l i c o l l i s ) i n 3. Compared to the lowlands..(Bendell 1955b, Casperson 1963), the general incidence of endoparasites was very low (7 per cent vs. 60 to 70 per cent). Also, gizzard worms found by Casperson (1963) i n 95 per cent of 22 adults were nearly absent (1/110) i n sub-alpine adults and y e a r l i n g s . Generally, the grouse of the high elevations appeared i n good health, however, 2 of the birds i n f e c t e d by tapeworms did not and require further examina-t i o n . The 2 heavily i n f e c t e d grouse (in t e s t i n e s were plugged with tapeworms) were both adult males. One was,collected i n July, 1965y and the second was,, shot i n May, 1966. Both were low i n b o d y . f a t compared to other males i n the,same ;periods, and the May b i r d was the smallest adult ;.collected during the e n t i r e study, at 1020 grams. Moreover, the testes of bothwere much smaller than average f o r the week i n which they were shot (July male - 0,08 cc. vs, 0.51 cc. for 8 other males; May male - 0.85 cc. vs, li.12 cc, f o r 12 others), a l -though the May male was hooting. Unfortunately more,detailed autop-sies were not c a r r i e d out so I can only speculate as to whether the tapeworms were the cause or the e f f e c t , o f the r e l a t i v e l y poor condition of these 2 grouse; or whether these grouse would or would not have died. 63 A preliminary survey of 50 blood f i l m s , 38 adult and 12 year-l i n g , was made. Only the presence or absence of blood parasites was noted (Appendix M). Leucocytozoon bonasae had the highest rate of incidence i n adults (72 per cent) and yearlings (92 per cent) followed by Tryanosoma sp. (72 per cent), M i c r o f i l a r i a v a g i n a l i s (60 per cent) and Haemoproteus canachites (56 per cent). These data were s i m i l a r to those c o l l e c t e d on the lowlands (Bendell 1955b) except f o r Haemopro- teus sp. which was less frequent i n the sub-alpine (56 per cent vs. 97 per cent). Haemoproteus sp. were not detected i n any of 5 females. During t h i s study only 2 instances of mortality i n chicks were observed. On August 9, 1965, an u n i d e n t i f i e d hawk was seen to capture a half-grown chick. The second was the decomposed remains of a two-week-old chick found July 28. The condition of the remains prevented any examination for cause of death. No natural mortality of chicks (or adults) was observed during the winter months, the period when most chicks apparently die (Zwickel and Bendell 1967a). New snow would have hidden the remains of any b i r d that had died or been k i l l e d . Even so, feathers from a male shot A p r i l 2, 1966, were s t i l l v i s i b l e on the snow 5 weeks l a t e r . Also, the body of a male I wounded A p r i l 23 was found and pointed by the dog two days l a t e r . These observa-tions suggest that had many grouse died on the winter range I studied, p a r t i c u l a r l y i n l a t e winter, some sign would have been found. In summary, the sub-alpine population of grouse appeared to be stable and s e l f - s u s t a i n i n g at a low density of hooting males. Y e a r l i n g females do not bred as on the lowlands. Incidence of disease and parasitism was low and l i t t l e predation was observed. These mortality factors did not account for e i t h e r the annual adult mortality, or the f i r s t winter mortality of chicks that i s known to occur (Zwickel and Bendell 1967a). DISCUSSION C r i t i c i s m s of the Data Perhaps the main f a u l t of t h i s study l i e s i n i t s short length. One year was i n s u f f i c i e n t to detect any trend i n numbers and to generalize on age and sex structure and production. That the sub-alpine breeding population appeared stable and i t s parameters were s i m i l a r to those on the lowlands i n the year of the study may have been e n t i r e l y c o i n c i d e n t a l . However, data from lowland studies i n d i c a t e that numbers and population parameters do not vary greatly between years so the given year may be t y p i c a l of others. The area chosen for the study may not be representative of where grouse l i v e i n the sub-alpine. Males were.found on the study area i n winter but few of those which passed through i n migration stayed there. Most seemed headed for higher mountains fart h e r west. Also, very few hens and chicks were found on the study area through the winter. How-ever, they were not found i n any other area searched i n e i t h e r the sub-alpine or the lowlands i n winter. Further, my analysis of the r e l a t i o n s h i p s between grouse and the sub-alpine habitat may be d e f i c i e n t i n that the c r i t e r i a I used to c l a s s i f y the study area (gross vegetation, a l t i t u d e , rock outcrops, and slope) were not those to which the grouse responded. The clear r e l a t i o n -ship I found between grouse and c e r t a i n kinds of habitat (Parkland, C l i f f and Ridgetop) may,be unrelated to what I see i n these types. 66 An attempt was made to examine t h i s , however, by choosing two areas (Beecher and Washington) with d i f f e r e n t g e o l o g i c a l , o r i g i n s and by considering a l l of the sub-alpine b i o t i c zone i n them. While great differences i n structure were found, the density of breeding males and of wintering males d i f f e r e d only s l i g h t l y . Nevertheless, considerable v a r i a t i o n i n habitat and grouse numbers has been found on the lowlands (Bendell and E l l i o t t 1967, Lance 1967, Zwickel and Bendell 1967) so only further study i n upland areas w i l l answer t h i s problem s a t i s f a c t o r i l y . The large s i z e (9.25 square miles) of the study area made inten-sive search of a l l parts impossible. Nor was i t possible to v i s i t most areas more than once or twice a week. While the number of hooting males recorded was considered accurate, the counts of resident s i l e n t males, resident hens, and hens with brood must be considered minimum estimates. In many cases samples were too small to apply tests of s i g n i f i c a n c e . In winter, f i n d i n g where grouse l i v e d on the study area was easier because of sign they l e f t behind. However, accurate counts were d i f f i c u l t because of the large area and interruptions caused by periods of bad weather and snow. The methods used i n t h i s study, p a r t i c u l a r l y the shooting of grouse, r e s t r i c t e d the kinds of data that could be gathered. They permitted data to be c o l l e c t e d on,the age structure of the population and replacement, body weight and condition, disease and parasitism, and moult and feeding habits which were desired for t h i s study. However, with shooting, i t was not possible to get subsequent observations on the same b i r d through the year needed to determine t e r r i t o r y s i z e , changes i n behavior, n a t u r a l mortality, and movements. It, was also possible that 67 shooting disturbed reproduction by causing some females to go unmated. Probably the most important shortcoming of the study was the inab i l i t y to find chicks i n late autumn and in winter. As a result, the primary question of this study remained unanswered: when and what caused the mortality of chicks over winter. Other related questions such as exactly when brood break-up occurred and in,what habitat chicks spent the winter also go unanswered. In spite of these drawbacks new data important to the general problem of what controls,grouse numbers were gathered. In addition, the results from the lowlands are strengthened and given a better perspec-tive. Size and Importance of the Sub-alpine Grouse Population One of the key findings.of this study was the discovery of a breeding population of blue grouse in the sub-alpine. Compared to low-land populations,on favourable habitat, the density was low (0.9 vs. 5 to 40 hooting males per 100 acres) but otherwise i t was the same in annual mortality of adults, ratio of yearlings to adults, and chicks per hen. These characteristics suggested the population was self-sustaining and probably stable. That no banded birds from nearby lowland study areas, no 'excess', of yearling males (Bendell and E l l i o t t 1967) and no.influx of females in late spring Zwickel 1965) were found, support this conclusion. Birds banded on the lowlands could have been expected to take up year round residency in the study area as they passed through the area during migrations. 68 But why the sparse population compared to the lowlands? I can only guess. The obvious explanation i s that climate or some related factor is acting directly on the grouse. Another possible explanation is that the sub-alpine grouse are of different genetic stock with less tolerance for neighbours. If true, then one might predict that they are generally more aggressive than lowland birds in the same way as Mossop (in preparation) found between sparse and dense populations in the lowlands. Yet another explanation is that food is,limiting, not. in quantity, but in quality. The sub-alpine is a relatively undisturbed and longlasting habitat which may,have most of i t s nutrients 'tied up' in a form unavailable to grouse. Burning of old heather (Calluna  vulgaris) in Scotland leads to increases i n red grouse probably through the release of nutrients (Moss 1969, Miller, Jenkins, and Watson 1966). But similar growth rates of chicks in summer in the sub-alpine and on the lowlands suggest that nutrients are not in short supply. A question I asked at the beginning was whether,there was important exchange of grouse between the high and lowland breeding populations. My data suggested there is very l i t t l e , i f any, movement of birds from the lowlands to join.the sub-alpine breeding population., Whether there is any in the reverse direction i s unknown but i t i s lik e l y . It i s well established that blue grouse exploit open habitat, and that they disappear when open habitat grows into dense forest. However, certain open habitats, particularly the dry ponderosa pine (Pinus ponderosa) ecotone.of the interior (Blackford 1958, Caswell 1954, and others) and the sub-alpine, are maintained by climatic con-ditions for long.periods of time compared to wetter forested zones. It i s conceivable .that forests go long periods.without f i r e resulting in the virtual elimination of blue grouse over large ,areas. Then, I ; suggest, the sub-alpine population is a reservoir from which grouse may move out.to openings in forest when f i r e (and logging in recent times) reoccurred. To this extent at least, the high land population may be very important to grouse on the lowlands on a long term basis. Habitat Selection Compared to the Lowlands In general, I found.the habitat used by,the sub-alpine breeding population to be structurally similar to that ut i l i z e d on the Vancouver Island lowlands (Bendell and E l l i o t t 1966) and reported for the dry interior (Boag,1966, Marshall 1946, Mussehl 1963 and.others). . That,is, habitat with relatively open tree canopy, and without dense shrubby ground cover. In the sub-alpine, the grouse preferred the parkland forest, the open edges of c l i f f s , and open parkland ridgetops in ascending , order of preference. There was,.however, some,variance between the sexes through the breeding season as found on the lowlands (Lance 1967, Bendell and E l l i o t t 1966 and 1967). Territorial; males, were more often found near sites offering good v i s i b i l i t y , especially when hooting, while hens in spring were usually near,sites f i r s t free of snow, and, in summer,(when with broods) in open and relatively level habitat. Also,, as on the lowlands,, grouse that replaced others that had been, shot in both the same year and,in the following, generally selected, the same kinds.of habitat used by the birds they replaced. . 70 The only sub-alpine habitat where resident grouse were not found and where they may have been expected to occur was the very open sub-alpine (Open Parkland) at high elevation. S t r u c t u r a l l y s i m i l a r lowland habitat supports high d e n s i t i e s of grouse (Zwickel and Bendell 1967a). The most l i k e l y explanation i s that the climate was l i m i t i n g but t h i s requires further study. Grouse did.venture i n t o t h i s habitat and even i n t o the true alpine i n autumn but l e f t again when snow came. In winter, males l i v e d in,the open upper elevations of the sub-alpine dominated by,large, heavy limbed trees. Snow reduced the crown cover of t h i s habitat (Parkland of summer) by approximately one^half and h i d a l l ground vegetation. S t i l l , i t did not d i f f e r greatly from the habitat used by males In the breeding season, at l e a s t i n structure. The wintering habitat of,females and chicks was not p o s i t i v e l y i d e n t i -f i e d but I believe i t ..was the dense forest of the lower sub-alpine and the upper parts of the Western Hemlock.Zone. I f true, hens and chicks use habitat very d i f f e r e n t to that u t i l i z e d at,other times of.the year by e i t h e r males or females. The Late Breeding Season i n the Sub-alpine Compared to the lowlands, my data show c l e a r l y a three to four-week delay i n a l l aspects of reproduction following the appearance of grouse i n early spring. I attempted to r e l a t e t h i s delay to differences i n the s t a r t of ,vegetative growth, i n temperature, and the melt of winter snow i n the sub-alpine and on.the lowlands (Table 12, page 71). "\ 71 TABLE 12 Comparison of the Main.Periods of Laying i n the Sub-alpine and Lowlands with Average Maximum and Minimum Temperatures i n the Two Weeks P r i o r to Laying, and with Snow Cover and Vegetative Growth at Laying 1965 1966 Sub-alpine Lowlands Sub-alpine Lowlands Approximate peak of lay i n g May 28 -June 10 May 1-10 June 1^10 May 1-10 Average Maximum, 44°F about 55°F 43°F 59°F-Temperature Average Minimum 32°F about 40°F O P 30 F 38°F. Temperature Snow cover 30-40% 0 97% 0 Vegetative Vaccinium Vaccinium Vaccinium Vaccinium growth buds leaves open, i n bud i n flower; breaking flowers out heads appearing The timing of nesting i n the sub-alpine was the same i n both years ' of ...the study while great differences occurred i n snow cover and vegetative growth. Late breeding i s normally a t t r i b u t e d to a dependence oh food supply f or egg,development and ultimately f o r chick growth (Perrins 1970) but here i t , d i d not appear to be the case. However, temperature p r i o r to la y i n g may be involved as i t was. s i m i l a r i n the. sub-alpine i n the two years and only s l i g h t l y lower than on the lowlands -when breeding began there. I t i s conceivable that as i n the a r c t i c , i f nesting i s delayed beyond a c e r t a i n point, the breeding season becomes too short to 72 s u c c e s s f u l l y r a i s e young. Yet, i n most years reproduction must be successful or else the sub-alpine population would have gone.to extinc-ti o n long ago. P a r t i c u l a r l y , as the population i s already under s t r a i n with longer maturation r e s u l t i n g i n y e a r l i n g females not breeding. Also, there i s a lack.of time for renesting which accounts for almost one-, quarter of the.successful broods on the lowlands. Seasonal Migrations. A l t i t u d i n a l migrations to and from highland wintering areas were f i r s t documented by Afrthony (1903) and have since been noted by many others (Johnson 1929, Boag 1966, Wing et a l . , 1944, Beer 1943, Mussehl 1960, Bendell 1955a, Lance 1967, King 1968, and others). Generally, my observations support these e a r l i e r studies i n that the males leave the lowland breeding ranges i n mid-summer and hens with broods i n l a t e summer and early f a l l ; and i n spring, the grouse return to lowland areas i n l a t e March. However, my data i n d i c a t e l i t t l e movement of adult males i n t o the sub-alpine before the t h i r d week of July, that i s , two weeks l a t e r than movement from the Vancouver Island lowlands was thought to begin (Bendell and E l l i o t t 1967). Moreover, I found hens with brood.began migrating e a r l i e r (August.1) and continued l a t e r (to mid-October) than reported (Bendell and E l l i o t t . 1 9 6 7 ) . But my data supports the contention that females migrate onto the lowlands a f t e r the males (Bendell and E l l i o t t 1967) and also the thought that lone hens leave the lowlands before hens with brood (Zwickel and Bendell 1967a). 73 Large flocks of grouse (10 to 50) i n migration were reported by, Bent (1932) and Caswell (1954). During the autumn of.1965 I did observe males i n small f l o c k s . o f two to s i x but never hens. Also, breakdown of broods has been reported i n conjunction with f a l l disper-sion (Mussehl 1960> Wing et a l . , 1944, Bendell 1955a). In t h i s study I found very few (4) lone chicks and no,flocks of purely chicks. Rather, chicks were s t i l l with hens i n family units and remained this way at l e a s t to early October. ; These units appeared to be migrating independently of each other. Lance (1967) working i n the same general area in,the autumn of 1966 made a s i m i l a r observation as.did Johnson (1929) on Mount Rainier. While the movements appear to.be stimulated by p h y s i o l o g i c a l processes (Simard 1964, Bendell 1955a), there i s considerable disagree-ment over the reasons.for migration to high elevations.when a l l other species of b i r d s migrate down mountains or south for .the winter. There may be good reason: blue grouse appear to be w e l l adapted morphologi-c a l l y and p h y s i o l o g i c a l l y to withstand winter storms and cold as,they possess excellent plumages and put on.heavy subcutaneous layers of f a t . On one occasion I observed an adult male go to roost on an exposed limb and remain there overnight through a severe b l i z z a r d when the pr o t e c t i v e s h e l t e r of a tree was only feet away. Average temperatures are.colder than at low elevations, however, f l u c t u a t i o n s from day-to-day, are smaller. Because i t i s colder and generally below freezing, moisture f a l l s as snow which remains s o f t and r e l a t i v e l y dry. And the grouse frequently roost i n t h i s powder snow as do most other tetraonids. At lower, elevations the snow, because of warmer and f l u c t u a t i n g temperatures, melts and freezes, thereby preventing snow roosting. Moreover, blue grouse are not able to cope with wet conditions, at l e a s t .as w e l l as ruff e d grouse (unpublished data from aviary s t u d i e s ) . In the sub-alpine, the snow cloaks the trees providing p r o t e c t i v e cover for feeding and from predators. Their food, co n i f e r needles, appears to be i n unlimited supply.and never d i f f i c u l t to get. A l l birds examined between October and,April were i n good condition i f body f a t can.be used as,an i n d i c a t o r . , L a s t l y , through the winter, almost no predators l i v e at high elevations. I observed no sign of avian predators, cougars, and only r a r e l y , that of a pine marten (Martes americana). Perhaps a better question to ask i s why do grouse migrate to lower elevations and breed there, Welty (1963) and Lack (1968) have argued that birds migrate to the a r c t i c because they have a greater chance o f . s u c c e s s f u l l y producing young and the same reasons may explain blue grouse movements. That y e a r l i n g hens nest on the lowlands but not i n the sub-alpine appears to support,this argument. Population Regulation on the Winter,Range Studies on the lowlands suggest the death rate or d i s p e r s a l of juveniles through winter i s the most important parameter i n regulating the densities of breeding populations of blue grouse (Zwickel and Bendell 1967a, Lance,1967). Two important objectives,of the present study were to f i n d how and when these juveniles die or disperse, and to t r y and :discover-ultimate causes f b r t h i s mortality or dispersion. 75 Lowland data indicate that the factor or factors are density-dependent and Zwickel and Bendell (1967a) suggest they might be predation, disease, or some form of t e r r i t o r i a l behaviour. To begin with, I attempted to observe brood break-up and dispersion of chicks through the autumn. But no actual brood break-up was documented. Moreover, few lone chicks were found although average brood size decreased significantly (3.38 to 2.61). Predation may account for much of this decline as one case of predation was observed.. Johnson (1929) re-ported that he saw chicks apparently lost and wandering aimlessly with the f i r s t heavy snow of winter. It was at this time that I lost complete contact with hens and.broods and so cannot either support or deny this observation.. However, f i r s t snow may,be the crux of juvenile mortality. At this time the juveniles must switch from a largely deciduous diet (King 1968 and this study) to a purely coniferous one. To adult grouse this, conceivably, would be no problem as they have done i t before. But the stress may result in chicks dying, especially i f brood break-up is occurring concurrently, Furthermore, juveniles have much smaller fat reserves.(Appendix M) than found on adults, which may be important in periods of stress. To find i f early winter snow might be important to juvenile mortality, I compared early winter snowfall (B.C. Snow Survey Bull., 1959-67) with lowland juvenile mortality over winter (Figure 13, page 76). Juvenile mortality i s calculated on the difference between numbers of juveniles in spring and autumn. The data for juvenile mortality for the lowlands was taken from Bendell and Zwickel (1966) and unpublished f i l e s . Clearly ,in seven of the eight years, a.strong Figure 13, A comparison of the per cent of autumn chicks l o s t over winter with e a r l y winter snow f a l l . r e l a t i o n s h i p between snow f a l l and mortality existed. Moreover, the odd point, Middle Quinsam Lake i n 1963, may be a sampling error as loss on Comox Burn.in the same year did co r r e l a t e with snow f a l l . Hence, these data suggest-that over-rwinter j u v e n i l e mortality i n blue grouse i s not density-dependent, as found by.Zwickel and Bendell (1967a), but dependent on environmental f a c t o r s . U n t i l more data i s gathered on the r e l a t i o n s h i p of j u v e n i l e mortality and early winter snow f a l l , however, caution should be exercised i n . g e n e r a l i z i n g on t h i s apparent c o r r e l a t i o n . Studies of other tetraonids suggest that a l l except sage grouse, (Centrocercus urophasianus) (R. Ryder and C l a i t Braun, person, comm.) may.regulate t h e i r numbers through behavioural i n t e r a c t i o n i n autumn and early winter. I found no evidence.for t h i s i n blue grouse. The males and females with chicks migrated at d i f f e r e n t times and i n winter l i v e d i n d i f f e r e n t h a b i t a t s . Moreover, the males were regula r l y seen i n autumn i n small fl o c k s and on,one occasion 12 to 15 i n d i v i d u a l s to-gether. Nevertheless, there may be. i n t e r a c t i o n within the brood unit i n t h i s period. From mid-January through to l a t e March a l l males I observed were alone and appeared to be spaced as though some kind of i n t e r a c t i o n was occurring then, whether t h i s i s important to grouse numbers i s also unknown.. Red grouse studies i n Scotland have found that poor q u a l i t y range produces poor q u a l i t y chicks which s u f f e r higher mortality over winter than chicks from good range (Moss.1969). Bendell and E l l i o t t (1967) suggest,the same may be true f o r blue grouse,- This mortality may occur through behavioral i n t e r a c t i o n r e l a t e d to some,aspect of the environment as suggested above. 78 I t i s d i f f i c u l t to understand how anything i n the sub-alpine, i n c l u d i n g food q u a l i t y , could d i r e c t l y influence <numbers on the low-., lands. P a r t i c u l a r l y as birds from d e c l i n i n g , stable, and expanding populations appear to winter together as noted by,Bendell and E l l i o t t (1967). (The same authors also note that the 'same winter range' supported much higher numbers i n past years). But th i s p o s s i b i l i t y cannot be overlooked as changes i n the sub-alpine habitat do occur between years, f o r instance;, a great d i f f e r e n c e i n cone crop was noted between the springs of 1965 and 1966. This d i f f e r e n c e was r e f l e c t e d i n the food,of grouse i n the two years. The p h y s i o l o g i c a l changes that took place i n the trees between crop and no,crop years are unknown but Townsend and H a l l (1970) found leaves of huckleberry bushes (V. . augusti-^ folium) lower i n nitrogen i n crop years. 79 SUMMARY 1. Blue grouse were studied i n the. sub-alpine of Vancouver Island over.a period of 14 months to determine the fate of chicks a f t e r breeding season, and to,determine the . l i f e h i s t o r y and population par-ameters of b i r d s which bred at high elevation. Animal populations flu c t u a t e i n number. I t had been shown by Bendell (1970), Chitty (1967), Healey (1967), and others that the fate of j u v e n i l e s before they entered the breeding population was the most important f a c t o r regulating the s i z e of animal populations. 2. Wherever po s s i b l e , the data wctc compared or, r e l a t e d to p a r a l l e l data from study areas on nearby lowlands. 3. The grouse were studied by observing them and making exten-sive c o l l e c t i o n s . 4. Collected grouse were weighed and aged, gonads were measured vol u m e t r i c a l l y , the amount of body f a t measured on a scale of 1 to 3, the i n t e s t i n a l i t r a c t examined f o r p a r a s i t e s , and the.crop contents analysed. Blood smears were made at time of.death. 5. From October to May most,precipitation f e l l as snow which remained on the ground i n t o mid-summer. Maximum and minimum tempera-tures averaged 22 and 12 degrees lower than on the lowlands i n spring and summer. The snow and lower temperatures, delayed vegetative growth, 1 to l*g months compared to the lowlands. 80 6. The sub-alpine was c l a s s i f i e d on the basis of a l t i t u d e , slope, forest,cover., and rock outcrops, i n t o s i x habitat types. These habitats were: Dense Forest, Open Forest, C l i f f , Parkland, and Ridgetop. The C l i f f and Ridgetop had no comparative types on,the lowlands. A l l grouse shot and observed were placed i n one of these h a b i t a t s . 7. The breeding population showed.a strong preference f o r Ridgetop, C l i f f , and Parkland habitat types i n . d e c l i n i n g order of use. Males appeared to s e l e c t display posts that offered the best chance to see and hear other grouse and provided escape cover. Hooting males and replacements f o r ones shot in,the same year and the following year, chose the same kinds of habitat. Migrating grouse were found i n a l l habita t s , although most were.seen.in the Parkland. 8. Grouse migrated from sub-alpine winter range to breeding areas during the l a s t week of March and the f i r s t week of A p r i l with the males about one,week ahead of hens. Males, and broodless females migrated back to winter range mainly i n early August,, while hens with brood migrated i n l a t e August through to October. Most spring movement appeared to be by f l i g h t , while i n autumn i t was mainly by foot. Change i n pho.toperiod appears to control these movements. 9. The males that wintered on the study;areas were not birds that had held t e r r i t o r i e s i n the same area i n the previous breeding season. Further, the birds that wintered on the area were not those, which took up t e r r i t o r y . t h e following spring. 10. The population of grouse that -reproduced i n the sub-alpine occurred at a density much lower than found on nearby .lowlands (0.86 81 vs. 4,8 t e r r i t o r i a l males per.100 acres). Hooting males were evenly spaced despite a heterogenous habitat which included large tracks of unpopulated dense f o r e s t . This suggests that i n s e l e c t i n g a song post, males reacted f i r s t to the presence of other males and, secondly, chose a l o c a t i o n . 11o The percentage of y e a r l i n g males and females i n the breed-ing population was s i m i l a r to that found on the lowlands (28 to 35 per cent) i n d i c a t i n g a stable population. No 'surplus' of yearlings was. found as had been hypothesized. 12. A l l events of the sub-alpine breeding season, following spring migrations were delayed approximately four weeks,compared to the lowlands. Hooting display,.the cycle of t e s t i c u l a r development, and : copulation came to a peak about the f i r s t week of June 13. Moreover, the breeding season was shorter than on the low-lands. This was r e f l e c t e d i n the.length of the period of hatch (5 to 6 weeks vs.. 9 weeks) and i n the time s i z e of testes exceeded,0.80 cc. (8 weeks vs. 12 weeks). The short mating season suggests that few hens that lose t h e i r clutches during l a y i n g or incubation could renest. 14. Y e a r l i n g females did not nest, probably due to slowness.in reaching maturity. This suggests that adult hens,were more successful than t h e i r lowland counterparts, that mortality of sub-alpine chicks i s lower, or there was immigration, 15. I n i t i a t i o n and regression in,the t e s t i c u l a r cycle and moult of wing primaries were synchronized i n both the sub-alpine and the 82 lowlands. Like the spring-an<i f a l l migrations, they were probably c o n t r o l l e d by change i n the photoperiod. 16. The peak of hatch occurred about the 10th of July as opposed to June 15th on the lowlands. 17. Chick growth was not accelerated to compensate for l a t e hatch. The e f f e c t s of the l a t e hatch c a r r i e d over into,one-year old and older b i r d s . Y e a r l i n g grouse, p a r t i c u l a r l y males, were s i g n i f i -cantly lower i n weight than t h e i r lowland counterparts (995 gms. vs. 1100 gms.) and averaged 60 grams l i g h t e r as f u l l adults. 18. In August, brood.size was s i m i l a r i n the sub-alpine and on the lowlands (3.18 vs. 3.38) but i n September brood s i z e i n sub-alpine chicks decreased to 2.6. The cause of t h i s decrease was not discovered. 19. Through the autumn most.(4 exceptions) chicks were i n broods with hens. S i g n i f i c a n t break-rup of breeds was not observed. 20. Causes of chick mortality through t h e i r f i r s t winter were not discovered. The period of brood break-up and/or f i r s t snow f a l l may be important. 21. Through the winter most males, i f not a l l , l i v e d separately from the hens and chicks. These males l i v e d i n areas dominated by very large heavy limbed trees .at high elevation. Wintering range of hens and chicks was not discovered. 22. Behavioural i n t e r a c t i o n between males and ju v e n i l e s may have occurred i n . l a t e winter when males appeared to be spaced out,in the s u i t -able parts of the winter range. No behavioural i n t e r a c t i o n was observed i n autumn. Literature Cited 84 Literatur-e Cited Annon. 1957-1967. Government of B.C. Snow Survey B u l l e t i n . Water Investigations Branch. Dept. of Lands,.Forests, and Water Resources, V i c t o r i a , B.C. Anthony, A. W. 1903. Migration of Richardson's Grouse. Auk 20: 24-27. Bauer, R.D. 1962. Ecology of blue grouse on summer range i n north-c e n t r a l Washington. Unpublished M.Sc. Thesis, Wash. State Univ., 81 pp. Beer, J . 1943. Food habits of the blue grouse. J . W i l d l . Mgmt. 7: 32-44. Bendell, J . F. 1954. A study of the l i f e h i s t o r y and population dynamics of the sooty.grouse, Dendragapus obscurus fu l i g i n o s u s (Ridgway). Unpublished Ph.D. Thesis, Univ. B r i t . Col. 155 pp. — — . 1955a. Age, breeding behaviour and migration of sooty grouse, Dendragapus obscurus fu l i g i n o s u s (Ridgway). Can. J . Zool. 33: 195-223. -—•. 1955b. Disease as a control of a population of blue grouse, Dendragapus obscurus f u l i g i n o s u s (Ridgway). Can. J . Zool. 38: 701-713. . 1955c. Age, molt and weight c h a r a c t e r i s t i c s of blue grouse. Condor 57: 354-361. — — . 1971. Population dynamics and ecology of the Tetraonide. XVth Int. O r i n i t h . Cong., The Hague. August 31, 1970. In press i n proc. of the Cong. and P..W. E l l i o t t . 1966. Habitat s e l e c t i o n in.blue grouse; Condor 68: 431-446. 1967. Behaviour and the regulation of numbers i n blue grouse. Can. W i l d l . Service Report Series, No. 4. 76 pp. Bendell, J . F., and F.C. Zwickel. 1966. M o r t a l i t y , p r o d u c t i v i t y , and population regulation i n blue grouse; Unpub. paper presented at the XIV In t e r n a t i o n a l . O r n i t h o l o g i c a l Congress, Oxford, 1966. Bent, A.C. 1932. L i f e H i s t o r i e s of North American gallinaceous b i r d s . U. S. Nat. Mus. B u l l . No. 162. 490 pp. Blackford, J . L. 1963. Further observations on the breeding behaviour of a blue grouse population i n Montana. Condor,65: 485-513. 85 Boag, D. A. 1965. Indicators of Sex, Age, and breeding phenology i n blue grouse. J . W i l d l . Mgmt. 25: 103-108. . 1966. Population a t t r i b u t e s of blue grouse i n SW Alberta. Can. J . Zool. 44: 799-814. —'• and J . W. Kiceniuk. M968, Protein and c a l o r i c content of lodgepole pine needles. For. Chron. 44: 1-3. Brooke, R. C. 1966. Vegetation -environment r e l a t i o n s h i p s of sub-alpine mountain hemlock zone ecosystems. Unpublished Ph.D. Thesis. Univ. of B r i t . Col. 225 pp., App. 110 pp. Bump, G. R., R. W. Darrow, F. C. Edminster, W. F. Crissey. 1947. The ru f f e d grouse, l i f e h i s t o r y , propagation, and management. The H o l l i n g Press Inc., Buffalo, New York. 915 pp. Burger, J . W. 1948. The r e l a t i o n s h i p of external temperature to. spermatogenesis i n the male s t a r l i n g . J . Exp. Zool. 109: 259-266. C o l l i a s , N.E. and R.D. Taber. 1951. A f i e l d . s t u d y of some grouping and dominance r e l a t i o n s i n ring-necked pheasant. Condor 53: 265-275. Casperson, K.D. 1963. V i s e r a l Parasites i n blue grouse, Dendragapus  obscurus fu l i g i n o s u s . (Ridgway). Unpublished B.Sc. Thesis. Univ. B r i t . C ol., 34 pp. Caswell, E. B. 1954. A preliminary study on the l i f e h i s t o r y and ecology of the blue grouse i n west c e n t r a l Idaho. Unpub-l i s h e d M. Sc. Thesis. Univ. Idaho, 105 pp. C h i t t y , D. 1964. Animal numbers and behaviour, i n : F i s h and Wild-l i f e : A memorial to W. J . K. Harkness. Ed. J . R, Dymond-Longmans. Canada, pp. 41-53. . 1967. What regulates b i r d populations. Ec o l . 48: 698-701. Choate, T. 1963. Habitat and population dynamics of w h i t e - t a i l e d ptarmigan. J . W i l d l . Mgmt. 27: 684-699. Clark, P. J . and F. C. Evans. 1954. Distance to.nearest neighbour as a measure o f . s p a t i a l r e l a t i o n s h i p s i n populations. E c o l . 35: 445-453. E l l i o t t , P.W. 1965. Factors 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 of blue grouse on.a summer range. Unpublished M.Sc. Thesis. Univ. B r i t . Col., 92 pp. Fowle, CD. 1960. A study of the blue grouse (Dendragapus obscurus (Say)) on Vancouver Island, B r i t i s h Columbia. Can. J . Zool. 38: 701-713. 86 Gibson, G. G. 1965. The taxonomy.and biology of s p l e n d i d o f i l a r i i n a e nematodes of the tetraonidae of B r i t i s h Columbia. Ph.D; Thesis, Univ. B r i t . Col., 235 pp. Hardy, G. A. 1954. The natural h i s t o r y of the.Forbidden Plateau area, Vancouver Island, B r i t i s h Columbia. B u l l . P r o v i n c i a l Mus., V i c t o r i a , B.C. 43 pp. Healey, M. C. 1967. Aggression and self-rregulation of population s i z e i n deermice. E c o l . 48: 377-392. Heebner, G. C. 1956. A study of the l i f e h i s t o r y and ecology of the. blue grouse in.west c e n t r a l Idaho. Unpublished M. Sc. Thesis. Univ. Idaho. 51 pp. Henderson, U. B, 1960. A study of blue grouse on summer range; north-c e n t r a l Washington. Unpublished M.Sc. Thesis. Wash. State Univ. 96 pp. Hoffman, R. S. 1961. The q u a l i t y of the winter food of blue grouse. J . W i l d l . Mgmt. 25: 209-210. Jenkins, D. 1963. Population control i n red grouse (Lagopus 1. s c o t i c u s ) . Proc. XIIth Intern. Ornith. Congr. 690-700. = , A. Watson and G. R. M i l l e r . 1963. Population studies on red grouse (Lagopus 1. scoticus) i n north-east Scotland. J . Anim. E c o l . 32: 317-376. Johnson,.R. A, 1929. Summer notes on the sooty grouse of Mount. Rainier. Auk 46: 291-293. Johnston, D. W. 1956. The annual reproductive cycle of,the C a l i f o r n i a g u l l , part I: C r i t e r i a of age and the testes cycle. Condor,, 58: 134-162. King, R. D. 1968. Food habits i n r e l a t i o n to the ecology and popula-t i o n dynamics of blue grouse., Unpublished M.Sc. Thesis. Univ. B r i t . Col. 62 pp. Kr a j i n a , V. 1965. Biogeoclimatic zones and c l a s s i f i c a t i o n of B r i t i s h Columbia. Ecol..West. N. Am. 1: .1-17. : . 1969. Ecology.of forest trees i n B r i t i s h Columbia. E c o l . of West. N. Am, 2: 1-146. Lack, D. L. 1966. Populations o f r b i r d s . Cladrendon,Press, Oxford. V + 341 pp. — . 1968. Bir d migration and natural s e l e c t i o n . Oikis 19: 1-9. 87 Lance, A. N. 1967. A telementry study of dispersion and breeding biology i n blue grouse. Unpublished M.Sc. Thesis, Univ. B r i t . Col. 100 pp. Lo f t s , B. and R. K. Murton. 1968. Photoperodic and p h y s i o l o g i c a l adaptations regulating avian breeding cycles and t h e i r , e c o l o g i c a l s i g n i f i c a n c e ; J . Zool., Lond. 155: 327-394. Marshall, W. Hi 1946. Cover preferences, seasonal movements, and food habits of Richardson's grouse and ru f f e d grouse i n southern Idaho. Wilson B u l l . .58: 42-52. M i l l e r , G. R., D. Jenkins and A. Watson. 1966. Heather performance and red grouse populations. J . Appl. E c o l . 3: 313-326. Moss, R. 1969. A comparison of red grouse (Lagopus 1. scoticus) stocks with the production and n u t r i t i v e value, of heather (Calluna v u l g a r i s ) . J . Anim. E c o l . 38: 103-122. Mossop, D. H. 1971. Aggression and population regulation i n blue grouse. M.Sc. Thesis i n preparation. Univ. of B r i t . Col. Mussehl, T. W, 1960. Blue grouse production, movements, and popula-tions i n the Bridger Mountains, Montana. J . W i l d l . Mgmt. 24: 60-68. — — : - . 1963. Blue grouse brood cover . s e l e c t i o n and land-use im p l i c a t i o n s . J . W i l d l . Mgmt. 27: 547-555. Peck, M. E. 1961. A manual of the higher plants of Oregon. Binfords and Mort, Portland. 936 pp. Per r i n s , cT,M.'J;-i970.: The timing of birds ' b r e e d i n g seasons Auk 112: 242-255, ' .. - "'. ' Peterson, E. B. 1965. The subalpine. mountain hemlock zone, part I: phytocoenoses. . E c o l . West. N. Am., 1: 76-78. Robinson, W. L. 1969. Prog, report on spruce grouse studies i n . Michigan. Not published. Rogers, G. E. 1968. The blue grouse i n Colorado. Techn. Publ. No. 21, Colorado Dept. Game, F i s h and Parks. 64 pp. Roseberry, J . L. and W. D. Kilmstra. 1965. A guide to age determina-t i o n of bobwhite q u a i l embryos. I l l i n o i s Nat. H i s t . Survey B i o l . Notes No. 55. 4 pp. Seagraves, P, 1970. Stepwise discriminant a n a l y s i s . Mimeo. paper, Cumputer Center, U.B.C, 88 S e i s k a r i , P.. 1962, On the winter ecology of,the c a p e r c a i l l i e , Tetrao  urogallus, and the black grouse, Lyrurus t e t r i x , F i n n i s h Game Found., papers on Game Res. 22: 1-119. Simard, B. J, 1964. The t e s t i c u l a r cycle of blue grouse (Dendragapus  obscurus f u l i g i n o s u s ) and i t s r e l a t i o n to age, breeding behaviour, and migration. Unpublished M.Sc. Thesis. Univ. B r i t . Col. 113 pp. Skinner, M. P. 1927. Richardson's grouse i n the Yellowstone.park. Wilson B u l l . 39: 208-214, Smith, Ni D. and I. O.Buss. 1963. Age determination of blue grouse. J.. W i l d l . Mgmt. 27: 566-578. Standing, K.S. 1960. Factor s . i n r e l a t i o n to population f l u c t u a t i o n s i n the blue grouse. Unpublished Ph.D. Thesis. Wash. State Univ. 93 pp. Steele, R. G. and J . H. T o r r i e . 1960. P r i n c i p l e s and procedures of, s t a t i s t i c s . McGraw-Hill Book Co., Toronto. 481 pp. Stewart, P. A. 1967. Hooting of Sitka blue grouse i n r e l a t i o n to weather, season, and time of day. J . W i l d l . Mgmt. 31: 28-33. S t i r l i n g , I. G. 1965. Studies of the holding, behaviour, and n u t r i t i o n of captive blue grouse. Unpublished M.Sc. Thesis. Univ. B r i t . Col. 125 pp, and J.-F. Bendell. 1966. Census of.blue grouse with re-corded c a l l s of a female. J . W i l d l . Mgmt. 30: 184-187. . 1968. Aggressive behaviour and.the dispersion of female blue grouse. Can. J . Zool. 46: 405-408. 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. Townsend, L. R. and Ii V. H a l l . 1970. Trends i n nutrient l e v e l s of lowbush huckleberry leaves during four consecutive years of sampling, l e Nat. Can. 97: 461-466. Watson, A. 1965. A population study of ptarmigan (Lagopus mutus) i n Scotland. J . Annim. E c o l . 34: 135-172. Weeden, R. B. 1964. S p a t i a l separation of sexes i n rock and.willow ptarmigan i n winter. Auk 81: 534-541. Weise, C. M. 1967. Castration and spring migration i n white-throated sparrows. Condor 69: 49-68. Welty, J, C. 1963. The l i f e of b i r d s . A l f r e d A. Knopf, New York. 546 pp. Westerkov, K. 1965. Winter ecology of the partridge (Perdix,perdix) i n the Canadian p r a i r i e . Proc. N. Z. E c o l . Soc. 12: 23-30. Wing, L,, J . Beer and W. Tidyman. 1944. Brood habits and growth of blue grouse. Auk 61: 426-440. Zwickel, F. C. 1965. Early mortality and the numbers of.blue grouse. Unpublished Ph.D. Thesis, Univ. B r i t . C o l . , 153 pages. and.J. >F. Bendell. 1967a. Early mortality and the regulation of numbers i n blue grouse. Can. J . Zool. 45:,817-851. : . 1967b. A snare for capturing blue grouse. J . 'Wildl. Mgmt.. 31: 202-204. Zwickel, F. C. and A. N. Lance. 1966. Determining the age of young blue grouse.. J . W i l d l . Mgmt. 30: 712-717. APPENDIX A Grouse c o l l e c t e d i n the sub-alpine from May, 1965, through June,. 1966, divided i n t o adult, y e a r l i n g , and juv e n i l e s and sex. APPENDIX A Grouse c o l l e c t e d i n the sub-alpine from May, 1965, -through June, 1966. (M=male, F=female) Year Month Jan. Feb. Mar. Apr. May June J u l y Aug. Sept. Oct. Nov. Dec. M F M F M F M F M F M F ...M F M F M F M F M F :M F 1965 Adult - - - - - - - - 13 - 12 - .12,1 11 4 4 .3 2 - 3 - 2 -Yearling - - - - - - - - 2 - 3 2 2 - 4 2 - - - - - - - -Juvenile - - - - - - - - - - - - 3 1 2 1 2,3 1 1 1 - - -1966 Adult 1 - - - 4 - 5 - 12 1 - - - - - - - - - -Yearling - - - - 1 - 1 1 3 1 1 - - - - - - - - - - -Juvenile - - - - - - - - - - - - - - _ _ _ _ _ _ _ _ _ _ To t a l Adult 1 - - - 4 - 5 - 25 1 12 - 12 1 11 4 4 3 2 - 3 - 2 -Yearling - - - - 1 - 1 1 5 1 4 2 2 - 4 2 _ _ _ _ - _ _ -Juvenile - - - - - - - - - - - - 3 1 2 1 2 3 1 1 1 - - -APPENDIX B St r u c t u r a l d e t a i l , per cent,of study area, and a l t i t u d i n a l range of the s i x sub-alpine habitats shown i n Figure 2 (page.11) with a b r i e f d e s c r i p t i o n of each. APPENDIX B Str u c t u r a l d e t a i l , per cent of study area, and a l t i t u d i n a l range of the six_sub-alpine h a b i t a t s . Remarks on each habitat follow on page 94. Habitat Type (per cent of ground covered) Dense Forest Open Forest C l i f f Ridgetop Parkland Open Parkland Conifers 75 - 100 50 - 80 1 0 - 6 0 10 - 25 10 - 25 0 - 10 Shrubs 0 - 40 30 - 90 2 5 - 6 5 25 - 65 70 - 90 . 40 -100 Open Ground 50 - 50 1 0 - 60 2 25 - 80 3 4 . 25 - 50 0 - 5 4 0 - 50 3 Per cent of T o t a l Study Area 32 6 33 4 17 8 A l t i t u d e range of type ( f t . ) 3100-4000 3100-4000 3100-4400 3500-5000 3700-5000 4000-4500 = mainly bare ground under trees = rock, bare s o i l , ponds, and bogs = mainly open rock = rock and bare ground 94 Appendix B (continued) (a) Dense Forest. (b) Open Forest. (c) C l i f f . (d) Parkland (e) Open Parkland. (f) Ridgetop. This was typically found at the lower elevations of the sub-alpine and had almost continuous cover by heavy forest. This applied to relatively level areas at lower, elevations where tree cover was heavy but interrupted by bogs, ponds, and rock out-croppings. Shrubs were usually dense in and around these openings. This applied to slopes.interrupted by many open rock c l i f f s and outcroppings but with the terraces between c l i f f s typically very shrubby and with dense clumps of trees. It was found mainly at lower elevations, that i s , under 4000 feet. It referred to the higher elevations of the sub-alpine where trees occurred in clumps with large natural spaces between. T a l l shrubs were found adjacent to the tree clumps while short shrubs domin-ated the open spaces. Generally, the terrain was-relatively level and rock outcrops and c l i f f s unim-portant. . This applied to level.tops of mountains particularly in the Beecher area where trees were small and few in number and there were ..large exposures of rock. This applied to ridges with l i t t l e vegetation on top and which had steep slopes on two sides permitting good v i s i b i l i t y in most directions. Figure 14. Ridgetop habitat of Mount Washington. Figure 16. Photo of Parkland habitat showing open space between tree* clumps. Figure 17. Open Parkland habitat of higher elevations Figure 20 . Winter range i n late February. Figure 21. Blue grouse roost tree i n January. Figure 22. Roost tree i n March. Figure 23 . Immature sub-alpine trees encased i n snow are not used as roost trees. Figure 24. Blue grouse winter range i n January. Figure 26. Typical sub-alpine brood range. APPENDIX C Structure of the habitat types lowland blue grouse range APPENDIX C St r u c t u r a l descriptions of the habitat types of lowland blue, grouse range ;,.giyen i n percentages Middle Quinsam Lake 1 (a) (b) ..(c) (d) 2 Comox Very Open Open, Dense Very Dense Burn Conifers 2 28 45 75 0 - 1 3 Shrubs 24 31 48 . 55 0 - 2 Logs and Stumps 14 11 24 15 10 - 15 Herbs, Bracken 37 49 _51 49 22 - 68 Duff 68 73 81 83 7 - 23 Bare S o i l and Rock 24 17 3 5 12 - 52 = from E l l i o t t , 1965 = from Zwickel, 1965 - includes small deciduous.and very small conifer trees APPENDIX D A chart showing sub-alpine c l i m a t i c data f o r May 1965 to May, 1966: r a i n f a l l , snow pack, and temperatures. 102 APPENDIX D Weather Data The graph that follows summarizes the weather data c o l l e c t e d i n the sub-alpine during the course of th i s study from May, 1965, to June, 1966. Snow depth on the ground at 1,000, .3,000, and 4,500 feet was measured weekly. R a i n f a l l was measured d a i l y and t o t a l l e d f o r each week. Maximum and minimum temperatures were taken d a i l y when I was i n the f i e l d . In winter, when data were incomplete, an estimate of the .average weekly maximum and minimum was made. The average weekly maximum and minimum temperatures are shown f o r the lowlands f o r com-. parison f o r the months of May, June, and July i n 1965 and A p r i l and May i n 1966. In 1965 the f i r s t f r o s t came to the sub-alpine in.the f i r s t week.of September. The f i r s t snow came i n the second week of October but snow did not remain f o r the winter u n t i l the f i r s t week.of Novem-ber.. Snow covered the ground with a continuous layer u n t i l the l a s t week of March, 1966, when a.series of warm days exposed c l i f f edges and ridge tops. No r a i n f e l l i n May, 1966, although a small amount was recorded in,May, 1965. In 1965, l i t t l e snow remained on , the ground by mid-June whereas some snow remained i n 1966 through to l a t e August. This r e f l e c t e d the great difference i n the two winters of th i s study. Figure 1 Climatic data for May, 1965. to May, 1966: rainfall, snowfall, and temperature. Maximum and minimum temperatures are weekly averages. Rainfall is the total for the week. APPENDIX E Food of grouse i n the sub-alpine with tables and a b r i e f d e s c r i p t i o n of major items. 105 APPENDIX E Food of Grouse i n the Sub-alpine The crops of a l l birds c o l l e c t e d , i n the sub-alpine were analyzed and these data augumented by f i e l d observations. During the study, 124 crops were-collected of which ;113 contained items of food. The crops.are classed i n t o age and sex groups - TABLE 1 i n Table,1. Grouse Class T o t a l With Food, i n Crop Percent with Food i n Crop Adult Males 79 72 91 Yea r l i n g Males 16 14 88 Females 15 14 93 Chicks 14 13 93 T o t a l 124 113 The fresh volume, oven-dried weight, and incidence were recorded for each item. The r e s u l t s of the analyzes are given i n Tables 2, 3, 4, and.5. In the following paragraphs these r e s u l t s are looked at b r i e f l y under the headings: Coniferous Foods, Angiosperms ,and Ferns, and Animal Mat t e r . Coniferous Foods Needles, buds, and,cones of conifers (mountain hemlock, amabilis f i r , pines) occurred i n 92 per cent (36/39), of the crops of adult males c o l l e c t e d between November and May and accounted f o r 93 per cent of the TABLE 2 The food of adult males c o l l e c t e d at high elevation on Vancouver Island.recorded by frequency of occurrence ( f o ) , volume, and dry weight. The number of empty crops i n each month's, sample s i z e i s shown i n brackets. Month Mar-Apr. May June Jul y August ,Sept.- Oct. Nov.T-Jan. Sample Size 9(1) 26(1) 9(1) 12(2) 11(2) 6(0) 6(0) T o t a l Volume 82.7 ml 175.5 ml 41.7 ml 32. 3 ml 60.2 ml 45. 4 ml 116.9 ml-T o t a l Dry Weight 21.60 gm 36.79 gm 4.87 gm 3. 77 gm 7.58 gm. 6. 47 gm 33.13 gm f % % f % % f % % f % % f % % f % % f % % Comm. Name o v o l . wt. . . V O l . wt. o v o l . wt. o v o l . wt.. o v o l . wt. o v o l . wt. o v o l . wt. U n i d e n t i f i e d 1 0.1 0.1 3' '2.3 0.8 2 3.3 2.4 1 Tr Tr 3 0.1 0.9 1 2.6 2.0 1 Tr Tr Mtn. Hemlock 7 57.8 60.7 20 74.8 80.4 2 11.7 21.3 4 4.9 6.9 - 3 2.6 4.5 3 33.4 32.3 Amabilis F i r 2 3.8 4.0 2 4.2 1.9 2 6.2 16.7 1 1.5 2.3 1 Tr .0.1 1 . T r 0.1 -White Pine 2 38.0 32.7 - - - - - -Juniper - - - - - - 1 Tr. 0.1 Douglas F i r - ' 1 7.4 10.0 - - - - 1 25.2 25.9 Lodgepole Pine* - - - - - - 2 38.2 40.2 Red Alder - - - - 1 0.6 1.0 - -Huckleberry - 5 10.5 6.2 7 73.1 55.2 4 71.8 70.. 5 7 96.6 93.9 5 60.1 52.5 2 2.6 0.9 Moss, Lichen - 4 T r Tr - - - 1 Tr Tr 1 Tr Tr Red Heather 1 Tr Tr - - 1 0.9 1.2 1 Tr 0.1 2 8.1 9.2 1 0.1 0.1 White Heather - - - 1 Tr Tr - - -Alpine S a l a l - - - - 1 2.3 3.4 - -Bearberry - 1 Tr Tr - - - - 1 0.3 0.1 Copperbush - - 1 3.8 2.8 - - - -Wh. Rhododendron - 1 0.3 0.1 - - - - -Luetkea - - - - - 2 20.0 25.2 1 Tr Tr T r i g . Blackberry - - - - 1 1.3 1.0 -Spiraea - - - 1 Tr 0.2 - - -Parrot's Beak - - - 2 10.2 8.2 1 0.3 0.3 - -Stone Crop - 1 Tr Tr - - - - -V a n i l l a Leaf - - - - - 1 5.0 2.7 -Grass - - 1 Tr 0.3' - 2 Tr 0.1 -H o r s e t a i l - - 1 1.7 1.0 - - — -Lycopodium - 1 Tr Tr - - - - -Heuchera - - - 1 Tr 0.2 - - -Parsley Fern - - - 1 10.5 9.6 - - -Insets - 2 Tr Tr 1 Tr 0.4 1 Tr Tr 1 Tr Tr - -G r i t 1 0.2 2.2 1 Tr 0.1 - - - .2 Tr 2.6 •-* - from 2 birds collected on. Apex Mountain near Penticton, B.C. - S c i e n t i f i c names of plants i n this table and i n the following tables are given i n Table.6. TABLE 3 Food of y e a r l i n g males c o l l e c t e d at high e l e v a t i o n on Vancouver Island YEARLING' MALES Month Mar-Apr. May June -..July .August T o t a l Volume.. 22.9 ml 26.0 ml 42.1 ml 6.3 ml 27.8 . ml T o t a l Dry Weight 5.64 gm 6.84 gm 4.31 gm 0.9,8 gm .- 3.42 gm Comm. Name f % % f % % f % % f % ...-%:._ f % % o v o l . wt. o v o l . wt. o v o l . wt. o v o l . - wt. o v o l . wt. U n i d e n t i f i e d _ 1 ; 1.5 1.8 . 1 0.8 0.4 Mtn. Hemlock 1 56.7 51.5 - - - — Amabilis F i r 1 43.3 48.5 2 99.9 99.9 - - -Huckleberry - - 4 99.9 99.9 1 98.5 94.9 :- 3 98.6.97.2 T r i g . Blackberry - - - - . 1 1.0 0.8 G r i t 1 Tr 3.3 2 ..Tr 1.5 TABLE 4 Food o f , a l l females c o l l e c t e d at high e l e v a t i o n on Vancouver Island ALL FEMALES Month Mar-Apr. May June Ju l y August Sept-Oct. Sample Size 1(0) 2(0) 2(0) 1(0) : 6(1) 3(0) T o t a l Volume 16.4 ml 6.4 ml 8.3 ml 46.9 ml 16.1 ml 37.6 ml T o t a l Dry Weight 5.18 gm 0.07 gm 1.03 gm 5.90 gm 2.4.0 gm 4.46 gm Comm. Name f % % f % % f % % f % % . f - % : % f % % o v o l . wt. o v o l . wt. o v o l . wt. o v o l . wt.• o v o l . wt. o v o l . wt. U n i d e n t i f i e d _ _ 1 5.5 4.7 1 , Tr Tr 1 Tr 1.1 Mtn. Hemlock 1 99.9 99.9 2 Tr 58.6 - - 1 Tr Tr -Amabilis F i r - - - - - 1 12.5 25.8 Copperbush - - 2 30.1 31.8 - - -Huckleberry - 1 Tr 27.1 1 69.9 68.2 1 6.4 6.0 4 98.7 98.3 3 38.3 36.2 Stone Crop - - - 1 Tr 1.2 - -Bearberry - - - 1 21.7 26.5 - -Strawberry - - - 1 63.8 62.4 - -T r i g . Blackberry - - - - - 1 4.3 3.2 Alpine S a l a l - - - - - 2 34.0 25.5 Red Alder. - - - - - 1 5.0 5.5 Saxifrage - - - - 1 Tr 1.5 -Lycopodium. - - - - - 1 Tr 0.3 Moss - - - 1 Tr Tr - -Insects — 1 Tr 14.3 — — — — TABLE 5 The plant food eaten by juveniles i n the sub-alpine i n 1965. JUVENILES--PLANT MATERIAL Month July August September,. Oetober November Sample Size 4(0)- 5(0) 2(0) KO) T o t a l Volume 3.8 ml 2.7 ml 76.6 ml 3.2 ml 12.2 ml T o t a l Dry Weight 0.27 gm 0.28 gm 7.25 gm 0.39 gm 2.20. gm Comm. Name f % % f % % f % % f %. . . % f % % o v o l . wt. o v o l . wt. o v o l . wt. o v o l . wt. o v o l . wt. Un i d e n t i f i e d 2 52.5 38.6 1 Tr 0.3 2 2.5 3.6 1 Tr 2.8 _ Mtn. Hemlock - - - 1 -Tr -,3.4 42.6 60.8 Amabilis F i r . - - - 2 18.8 28.4 -Red Alder - - 1 Tr 0.2 - -Huckleberry 2 29.0 34.2 2 88.9 95.3 3 36.5 42.4 2 75.D 59.9 1 13.1. 6.6 V a n i l l a Leaf - - 1 Tr 0.2 - -Moss & Lichen - - - 1 Tr. Tr - l Tr 0.3 Hawkweed 2 8.0 16.5 1 7.4 2.2 - - -T r i l i u m 1 2.5 2.2 1 3.7 2.2 - - -S a l a l - - 2 6.8 8.1 - -Alpine S a l a l - - 1 14.4 12.0 - -T r i g . Blackberry - - 2 15.8 13.2 -Red Heather - - 1 Tr 1.0 - -Luetkea - - - 1 6.2 6.6 l 12.3 11.5 Saxifrage spp. - - - - 1 18.0 13.5 Parsley Fern - - - - l 14.0 8.0 Lady Fern 1 8.0 8.4 2 22.9 19.0. Note: Animal material i s shown on page 110. TABLE 5 (Continued) Animal material taken by juveniles i n the sub-alpine i n 1965. Quantities were too small to measure volumetrically so per cent of volume and per cent of dry weight were not calculated. Only the number of animals and their, dry-weight are given. JUVENILES--ANIMAL MATERIAL Month July August September October , November Sample Size 4(0) 3(1) 5(0) -2(0) -1(0) T o t a l Dry Weight 0.044 gm 0.053 gm 0.049 gm 0.00 gm 0.00 gm Comm. Name f Dry- f Dry f Dry f . D ry f - -. Dry o No. Wt. 0 No. Wt. 0 No. Wt. 0 No. Wt. 0 No. • Wt. Diptera-U n i d e n t i f i e d 2 2 0,003 - - -Mus cidae 1 1 0.001 - - - -Empididae 1 1 0.0061,5 - - -A s i l i d a e 1 2 cobs'1' - - - -Simuliidae - 1 1 0.001 - - -Hymenop tera- • Formicidae 2 2 0.002 2 23 0.011 2 8 0.037 - -Tenthredinidae 1 1 0.001 -Homoptera-Aphididae,, 3 6 0.001 1 1 0.001 - - -Lepidoptera-^-Unid. l a r v a 1 1 0.003 - 2 3 0.008 -Coleoptera-Stophylinidae 1 1 0.001 - - - -C o c c i n e l l i d a e :1 1 0.008 - 1 1 0.002 - -Unid.>larva - 1 1 0.002 - - -I Lahtharidae 1 1 0.002 - - - -Afchnida-Unid. species 3 18 0.008 1 5 0.008 1 2 0.002 -Mollusca-Gastropoda,slugs — 1 3 0.030 — — I l l TABLE 6 L i s t of plants and t h e i r s c i e n t i f i c names that appear i n the discussion on'foods used by blue grouse Common.Name S c i e n t i f i c Name Plants: Mountain Hemlock, Tsuga mertensiana.(Bong) Carr. Amabilis F i r Abies amabilis (Dougl.) Forbes White Pine Pinus monticola.Dougl. ex D. Don Alpine F i r Abies l a s i o c a r p a (Hook) Nutt Western Hemlock Tsuga heterophylla (Ra.fi) Sarg. Jack Pine Pinus contorta Dougl. ex Loud. Juniper Juniperus communis Pa l l a s Yellow Cedar Chamaecyparis nootkatensis (D. Don) Spach Red Alder Alnus rubra Bong. Huckleberrys Vaccinium deliciosum Piper, V. membranaceum Dougl. ex Hook V. o v a l i f o l i u m Smith ' i]] .;,... Red Heather Phyllodoce,empetriformis (£Jmith) D. Don White Heather Cassiope mertensiana (Bong) D. Don S a l a l Gaultheria shallon Pursh. Alpine S a l a l G. humifusa,(Graham) Rydb. Bearberry Arctostaphylos uva-ursa (L.) Spreng. Copperbush Cladothamnus pyrolaeflorus Bong. White Rhododendron Rhododendron a l b i f l o r u m Hook, Luetkea Luetkea pectinata (Pursh.) Kuntze T r a i l i n g Blackberry Rubus ursinus Cham. & Schlecht. Spiraea Spiraea d o u g l a s i i Hook. Pa r r o t s 1 Beak P e d i c u l a r i s racemosa Dougl. Stonecrop Sedum spp. V a n i l l a Leaf, Achlys t r i p h y l l a (J.E. SM.) D C Grass H o r s e t a i l Equisetium spp. L. Heuchera Heuchera o v a l i f o l i a Nutt. Strawberry Fragaria spp. (Tourn.) L. Saxifrage Saxifraga spp. (Tourn.) L. T r i l l i u m T r i l l i u m ovatum Pursh. Hieraceum Hieraceum g r a c i l e Hook Parsley Fern Cryptogramma c r i s p a (L.) R. Br.: ' Lady Fern.. Athyrium f i l i x - f e m i n a (L.) Roth. Lycopodium Lycopodium clavatiim L. I 112 t o t a l volume. Four crops from y e a r l i n g males c o l l e c t e d during the same, months contained conifer parts e x c l u s i v e l y . A.crop from.a female c o l l e c t e d i n A p r i l contained only :male cones of mountain hemlock; and one of two from May was 70 per cent hemlock needles (the second crop from May contained only ants). From June through October, conifer parts formed,6 per cent of the di e t of adult males and occurred i n 13 of 33 crops. The crops of.10 year-l i n g males and 12 females contained no conifer parts. Twelve chicks c o l l e c t e d i n July through September and November had taken no co n i f e r needles though both,from October contained some. A comparison of - the r e l a t i v e frequencies of mountain hemlock, amabilis f i r , yellow cedar, and white pine with the r e l a t i v e frequency of each i n the sub-alpine (Table 7) indicates that there may have been selec-, t i o n f o r mountain hemlock and white pine and that there was a clear s e l e c t i o n against yellow cedar. TABLE 7 Species Per cent of occurrence i n crops (dry weight) Per cent occurrence species i n S-of -A. Mountain hemlock 85 72 Amabilis f i r 4 10 White pine 11 2 Yellow cedar 0 13 Others 0 3 T o t a l 100 100 113 During f i e l d work, trees were examined at random to see i f they were used as food. A l l Pinus species (P. monticola, P_. contorta) may have been sought as most showed use by grouse f o r food whereas most trees of other species did not. Often a lone pine would have needles picked o f f when neighbour-ing hemlocks and f i r s did not, Needles and twig t i p s were the most commonly used parts of the.trees although staminate cones were taken i n A p r i l , May, and early June. P i s t i l l a t e cones were r a r e l y taken as they grew at the ends of limbs and at the tops of trees. Birds took not only needles grown i n the past year but also those up to at l e a s t 10 years old (determined by cross-sectioning small twigs where grouse had fed). Twig t i p s occurred most frequently i n spring crops, p a r t i c u l a r l y before new growth,began, although a f t e r terminal buds had swollen. Terminal buds were taken only as part of a,twig t i p with needles. There was a.great diff e r e n c e between 1965 and 1966 i n the u t i l i z a t i o n of cones. In 1965 they were nearly absent from the crops, whereas i n 1966, 10 of 12 adult male crops were f i l l e d with them, I held about 1000 cones and 250 needles). Cones of both mountain hemlock and amabilis f i r were found. The diff e r e n c e between years r e f l e c t e d the r e l a t i v e abundance of cones i n the two years on the study area. The trees grouse fed upon varied g r e a t l y , i n s i z e and age and appeared to be used by males (except possibly the Pinus species) f o r reasons other than as food sources. The trees used by males provided good song posts, good s h e l t e r from weather, or were e a s i l y reached from the ground. Other than a few Pinus monticola, that were.sick with b l i s t e r r u s t , a l l trees used f o r food appeared i n good health. 114 Angiosperms and Ferns Species of huckleberry (Vaccinium membranaceum, V, oval i f o l i u m , _V. deliciosum), were the most important group of non-coniferous plants i n the diet of male, female, and ju v e n i l e grouse i n the sub-alpine. Buds, flowers, f r u i t s , and leaves were u t i l i z e d throughout,the year. In adult males from November through May, 6 of the 7 per cent of the non-coniferous food was Vaccinium parts and they occurred i n 7 of 39 crops. From June through October Vaccinium parts accounted f o r 83 per cent of the food of males and occurred i n 23 (70 per cent) of 33 crops. Ten of 14 ju v e n i l e crops con-tained varying amounts of Vaccinium as did those of 9 of 15 females. A wide v a r i e t y of deciduous plants other than Vaccinium were used through summer and f a l l . Of these only three formed a s i g n i f i c a n t . p a r t of the die t i n any month. Parrots' beak. (Pedicularis racemosa), although uncommon i n the sub-alpine, occurred i n two crops and accounted f o r 10 per cent of the t o t a l food i n August. In July one b i r d consumed a quantity of the fern, Cryptogramma c r i s p a , which accounted f o r 11 per cent of the t o t a l food f o r the month. In September and October, Lutkea pectinata formed a prominent part of the crop contents of two bi r d s . . In the sub-alpine there was a clear s e l e c t i o n f o r Vaccinium shrubs. Large acreages of rhododendron (R. al b i f l o r u m ) , copperbush (Gladothamnus  p y r o l a e f l o r u s ) , and.other shrubs, plus many herbs and grasses, went v i r -t u a l l y unused. Animal Foods ; Animal matter formed a n , i n s i g n i f i c a n t part of the t o t a l d i e t f o r the older birds except, perhaps, hens during.laying. Only a few ants, which appeared to have been taken i n c i d e n t l y , occurred i n the.crops of 115 the males. The crop of the adult,female c o l l e c t e d during l a y i n g (May 18, 1966) contained only which were u n l i k e l y to have been picked up by accident./\ Three non-breeding y e a r l i n g females c o l l e c t e d i n May and June and a l l females (9) c o l l e c t e d i n other months had no animal matter i n t h e i r crops. Insects and/or arachnids occurred i n a l l (6) crops of chicks. From July and August, i n 3 of 5 crops from September, and i n 0 of 3.crops from October and November. Three s n a i l s occurred i n one of the August chicks as w e l l . In terms of per cent of dry weight of the d i e t , animal matter accounted f o r 15 per cent i n July and August and 6.7 per cent i n September. APPENDIX F Moult patterns of primary feather of sub-alpine grouse. 117 APPENDIX F Primary Moult The moult of wing primaries was noted f o r a l l grouse examined to learn i f i t s timing and progression d i f f e r e d from the lowlands. For the. months of June.through September, 1965, 60 grouse were a v a i l a b l e from the sub-alpine and 55 from the lowlands of which 54 of the former group and 49 from the l a t t e r had shed one or more primaries (below). Adult male Ye a r l i n g male Adult female Yearling female Sub-alpine Lowlands (Zwickel, unpub, data) 31 8 12 5 7 18 4 19 In May, no grouse examined was i n moult at high or low elevation. In June primary moult had begun i n some b i r d s but not i n others (below). Sub-alpine Started Not s t a r t e d Adult male 4 Yearling male 4 Adult female* -Ye a r l i n g females 2 *no sample,,for June 6 0 Lowlands Started Not started 5 3 0 1 In July, a l l birds examined had begun except 4 lowland adult females from the f i r s t week. From these data i t would appear that no diffe r e n c e existed i n the date when moult began at the two elevations except possibly i n adult males. 118 The progression of moult through the summer was studied by graphing the l a t e s t primary (numbering d i s t a l l y ) to be l o s t against date. This was. done,for a l l birds from the sub-alpine and lowlands. For t h i s a nalysis, the females were separated i n t o those with broods (37) and those without (11) as 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. them. Simple regression l i n e s were then drawn through the points f o r each class (Figures 1 and 2) and each tested f o r r e l i a b i l i t y , that i s , point s c a t t e r . A l l curves had greater than 95 per cent r e l i a b i l i t y except those.for adult and y e a r l i n g males from the lowlands. Nevertheless, when each class was compared at the two elevations using a discriminatory analysis t e s t at the 5 per,cent l e v e l (Seagraves 1970) no differences were found. I conclude, therefore, that the fa c t o r or factors i n i t i a t i n g primary moult and c o n t r o l l i n g i t s progression were the same i n the sub-alpine and on the lowlands. The regression l i n e s cannot be projected back i n time in.an attempt to determine s t a r t of moult. This i s because the moult of the f i r s t 3 primaries occurs much more r a p i d l y than that of the remaining primaries. The regression l i n e s f o r lowland grouse (Figure 2) show th i s to some,ex-tent as most of the lowland birds examined were i n . e a r l y stages of moult. Figure 3 shows the regression l i n e s f o r lowland and sub-alpine data combined. Q _ 2 - f QL J 1 1 L J U N E J U L Y AUG S E P T M O NT H Figure 1. Regression lines of Adult and yearling male, broodless female, and brood female primary moult in the sub-alpine . The mean (X) and slope (B) are shown. See text for reliability of the B values. Sample sizeiis shown in brackets. J U N E JULY M O N T H AUG S E P T Figure 3. Regression lines of the primary moult of the grouse from the sub-alpine and lowlands combined. APPENDIX G Observations on hens, nests, and broods, spring and summer, 1965 and 1966. APPENDIX G Observations on hens, nests, and broods, spring and summer, 1965 and 1966 Category Observations (a) Lone Hens (to July 20) 11 (b) Hens collected 2 adult, 3 yearling (c) Nests ( i) 5 eggs and adult hen (i i ) single egg; no nest (d) Broods (July only) 9; chicks collected from 4 (e) Chick remains 1; found July 28 This table summarizes observations and collections made of hens, nests, and broods during spring and early summer of 1965 and 1966. APPENDIX H A table of chicks and eggs used i n estimating hatch dates and time of l a y i n g . 125 APPENDIX H Date Observed What Seen Estimated Brood Age Estimated Hatch Date Estimated Start of Incubation Estimated Start of Laying Comments June 9 1 egg - - June 5 Appeared to be 4-5 days o ld when found. May 28 Adult hen v May 31 Ovary contain-ed developed f o l l i c l e s . J u l y 13 Ad. hen & 5 eggs - July 27 - 2 9 Jul y 1 - 3 June - 25 22 Nest c o l l e c t e d J u l y 17 Ad. hen & 1 chick 7 days J u l y 10 - 12 June 14 - 16 June - 7 5 Chick could not f l y ; may have been more. July 17 Hen & 1 chick 10 - 14 days July 5 June 9 May 31 Very weak f l y e r J u l y 19 Hen & 4 chicks. 15 days July 4 June 8 May 30 Flew w e l l . J u l y 25 Heri & ? chicks under 10 days July 20 June 24 June 15 Peeps only, chicks not seen July 25 Hen & 6 chicks 13 days Ju l y 12 June 16 June 7 Weak f l y e r s J u l y 25 Hen & 1 chick 13 days July 12 June 16 June 7 Only chick seen Ju l y 27 Ad. Hen & 6 chicks 17 days July 10 June 14 June 5 Flew well July 28 Chick , remains about. 14 days July 10 June,14 June 5 F u l l of maggots; dead 5-7 days? This table gives a l i s t of a l l hens, broods, and eggs used i n c a l c u l a t i n g hatch dates and time of egg l a y i n g . APPENDIX I The distance to nearest neighbour of hooting males on Beecher and Washington i n 1965, and on Browns i n 1966. APPENDIX I The distance to nearest neighbour of hooting males on Beecher and Washing-ton i n 1965, and on Browns,in 1966. Distance to Nearest Neighbour Number of Observations miles feet 0-. 10 0- 500 6 .11-.20 500-1050 11 .21-.30 1075-1575 12 .31-.40 1600-2100 18 .41-.50 2125-2700 4 .51-.60 2725-3200 52 APPENDIX J The per cent of yearlings i n undisturbed populations i n the sub-alpine and on the lowlands; and the replacement of shot t e r r i t o r y holders within the.same .and i n the following year. APPENDIX - J The per cent of yearlings i n undisturbed populations i n the sub-alpine and on.the lowlands; and the replacement of shot t e r r i t o r y holders within the same year and i n t h e ; f o l l o w i n g year. Lowland data are from E l l i o t t (1965) and Bendell and E l l i o t t (1967). O r i g i n a l ( T e r r i t o r y Holders Replacement Within Year. Replacement Between Years No.. Ad. Y r l . % Y r l . No.: Ad. Y r l . % Repl. No.- Ad. Y r l . % Repl. Sub-alpine (a) Collected 32 31 1 3 4 1 3 12 (4/33) .7 5 2 38 (12/32) (b) Not Collected 14 - - 5 - -Middle Quinsam (a) Collected 145 132 13 9 13 1 12 43 19 15 4 124 (13/30) (26/21) (b) Not Collected - - - - - - _ -! ; ; . : , APPENDIX K Predation observed i n the sub-alpine. 131 APPENDIX K. Predation observed in the sub-alpine between May, 1965, and June, 1966. (a) Avian On August 9th, 1965, an unidentified hawk (goshawk?) captured.a. half-grown chick from three flushed by the observer. The hen hissed and. clucked but did not pursue the hawk. Apparently the hawk was si t t i n g i n a nearby tree observing the hen and brood.' The attack occurred in Dense Forest habitat. The hen with brood was i n migration. On July 25, 1965, a goshawk made an unsuccessful attempt on a male grouse. The grouse was pointed by the dog but would not flush from very dense shrub growth. When I moved into the bush, the bird shot out and the hawk (not previously seen) swooped onto the grouse. The grouse escaped into other thick cover, and the hawk l e f t upon seeing the,dog. (b) Mammal Twice cougars were seen near grouse, although no actual predation was observed. On June 7, 1965, a cougar was found crouched under,a tree in which a male was hooting. The cougar was so intent on the grouse that I did not disturb i t u n t i l within 20,feet. It may have been attracted by the smell of droppings or the sound. On July 15, 1965, I flushed a cougar from bush only,30 feet from a hen with very young chicks. It is entirely possible that she could have been captured by the cougar in defending her brood.. APPENDIX .-L Parasites of grouse collected in the sub-alpine in 1965 and 1966. APPENDIX L The extent of p a r a s i t i c i n f e c t i o n of adult.and y e a r l i n g grouse c o l l e c t e d i n the sub:-alpine-in .1965 and 1966. Lowland data for, L.Q.L,. are from Bendell (1955b) and for M.Q.L. from Casperson (1963). Species of Pa r a s i t e S i t e of Infection Number Examined Number Infected Per cent Infected T o t a l Ad. and Per Cent of Y r l . Infected Ad. Y r l . Ad. Y r l . T o t a l Ad. Y r l . ' Sub-rAlp. L.Q.L. (103) M.Q.L. (22) Haemoproteus sp. blood 38 12 28 56 97 -a) canachites 1! , 23 5 60 41 , b) dendragapi II 5 2 13 17 , Plasmodium s p . l II 38 12 2 1 3 5 8 6 - -Leucocytozoon sp. II 38 12 40 80 85 -a) A 2 1 2 .3 17 b) bonasae 29 11 76 92 M i c r o f i l a r i a sp. II 38 12 40 80 80(94 3) -a) f l e x i v a g i n a l i s 23 6 60 50 b) B 2 8 3 21 25 Trypanosoma sp. II . 38 12 27 9 36 71 75 72 77 -Gheilospirura gizzard. 87 23 1 1 - 4 1 22 95 spinosa^ Rhabdometra i n t e s t i n e 87 23 2 1 3 2 4 3 39 36 n u l l i c o l l i s A s c a r i d i a II 87 23 1 2 3 1 8 3 14 - 14 bonasae Dispharynx.' proventri- 87 23 - - - -r. - 4 18 nasuta culus = status uncertain, may represent a new record. = species uncertain (Gibson, 1965 and Dr. Adams, pers. comm.) = Gibson (1965) = some may be Yseria sp.; not separated i n autopsies. APPENDIX M The seasonal change ;in amount of f a t of grouse i n the sub-alpine. 135 APPENDIX M Classes of Deposition of Fat During autopsy, the amount of f a t on the body of every b i r d was noted. This was done as a gauge on the bird's condition r e l a t i v e to others c o l l e c t e d i n the same month. I was also i n t e r e s t e d i n the change i n body f a t through the year. The amount of f a t was measured on a scale of 0 to 3 where 3 represented a b i r d with heavy f a t deposits. For t h i s s c ale, the width of the f a t l i n e along the p o s t e r i o r edge of the r i b cage was used, a l -though f a t elsewhere, p a r t i c u l a r l y the neck, was noted. (1 =1-4 mm., 2 = 4-8 mm., 3 = 8 mm. p l u s ) . The r e s u l t s are given i n Figure 1. Adult and y e a r l i n g birds are shown separately f o r January through. July a f t e r which they become.indistinguishable. Six females from A p r i l through July were i d e n t i c a l to males i n the same months and are included with them. Females were separated from the males only i n August and September when they c l e a r l y had less body f a t . Chicks to the age of s i x months are graphed separately as j u v e n i l e s . Adult males came i n t o the breeding season with very heavy deposits of f a t which they slowly l o s t through the months of June to August. Through t h i s period, the yearlings possessed less f a t than the adults but f a i l e d to show the same loss through early summer so that by July both age classes were s i m i l a r . In l a t e August the males began to put on f a t again but appeared to loose much of t h i s gain through October to December. Whether t h i s i s a general loss or only a function of the small sample c o l l e c t e d i s unknown but i t i s d i f f i c u l t to believe that i n a matter of 8 weeks they could climb back to the heavy f a t found on the January to March c o l l e c t i o n s . Most, i f not a l l , of the hens c o l l e c t e d i n August and September were brood hens and may have been low i n f a t due to the vigors of looking a f t e r t h e i r . c h i c k s . The j u v e n i l e s possessed much less f a t than older,birds and.did not appear to reach the condition of the older b i r d s i n t h e i r f i r s t winter. J _ H E A V Y 0) u < Lu 1 L I G H T • ADULT MALE • YEARL ING MALE H F E M A L E • J U V E N I L E JAN-MAR APR MAY J U N E JULY AUG S E P T OCT M O N T H Figure 1. The seasonal change in the amount of fat of grouse in the sub-alpine. NOV-DEC APPENDIX N Size of the weekly samples of sub-alpine grouse used in plotting change i n testicular volume through the year. APPENDIX N Size of the sub-alpine weekly samples of grouse used in Figure 9 showing seasonal change in testicular volume Month Week Adult; Yearling March 1 0 0 2 .0 0 3 1 0 A 3 1 April .1 2 0 2 0 0 3 3 1 4 1 0 May 1 2 1 2 2 1 3 12 3 4 7 1 June 1 2 1 2 4 1 3 2 0 4 2 2 July 1 0 1 2 8 0 3 1 0 4 3 1 August 1 ' 1 2 2 2 0 3 3 3 4 2 0 September 1 0 0 2 0 0 3 0 0 4 4 0 October to February — 8 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}]}"
                            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:
http://iiif.library.ubc.ca/presentation/dsp.831.1-0101920/manifest

Comment

Related Items