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Seasonal movements, habitat use, and winter feeding ecology of woodland caribou in West-Central British… Cichowski, Deborah B 1989

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SEASONAL MOVEMENTS, HABITAT USE, AND WINTER FEEDING ECOLOGY OF WOODLAND CARIBOU IN WEST-CENTRAL BRITISH COLUMBIA by DEBORAH B. CICHCWSKI B.Sc, Uni v e r s i t y of B r i t i s h Columbia, 1985 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE i n FACULTY OF GRADUATE STUDIES (Department of Forestry) we accept t h i s t hesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA August 1989 © D.B. Cichowski In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department of The University of British Columbia Vancouver, Canada Date DeC c V 3 , l ^ S ^ DE-6 (2/88) i 1 ABSTRACT Three levels of resource selection (seasonal movements and habitat use, winter feeding site selection, and forage selection), by two populations of woodland caribou (Rangifer tarandus caribou) 1n west-central British Columbia were examined to evaluate potential effects of logging on those populations. Seasonal movements and habitat use were determined by monitoring radiocollared adult female caribou; winter feeding site and forage selection were determined by following caribou tracks on winter ranges. Caribou moved from winter to summer ranges along relatively snow-free, low elevation migration routes. Itcha-IIgachuz-Rainbow caribou calved and spent the surrmer almost exclusively in alpine habitat in the Itcha, Ilgachuz and Rainbow Mountains; Tweedsmuir-Entiako caribou used a variety of alpine and forested habitats in and adjacent to northern Tweedsmuir Park during surrmer. During winter, caribou 1n both areas used predominantly low elevation forested habitats. In the Tweedsmuir-Entiako area, some use of alpine habitat occurred during mid-winter in the Fawnie Mountains. In the Itcha-Ilgachuz area, 5-15% of the radiocollared caribou spent the winter in alpine and subalpine habitat on the north side of the Ilgachuz Mountains. Rainbow Mountain caribou used alpine habitat in the northern Rainbow and Ilgachuz Mountains during the winter. On low elevation winter ranges in both areas, caribou selected Dry Lichen / Lichen Moss and Lichen Moss caribou habitat types. Mature pine forest cover types on low and poor quality growing sites were also selected by caribou during winter. Itcha-Ilgachuz caribou selected large Fescue-Lichen meadows in early winter and Dry Lichen / Kinnikinnick sites in the very dry, cold Sub-Boreal Pine/Spruce (SBPSxc) biogeoclImatic subzone in late winter. In late winter, the Tweedsmuir-Entiako caribou selected mature Moss/Seepage Forest - Aspen Forest caribou habitat types. Forest cover types selected were mature pine and pine/spruce forest cover types on medium quality sites. Throughout the winter, pine forests 1n both areas were used predominantly for cratering for terrestrial lichens. Caribou selected areas with high terrestrial lichen abundance for cratering. Snow characteristics (snow depth, snow penetrability) did not appear to influence crater site selection. Snow was often deeper at cratering sites than at non-cratering sites because sites that were selected for abundant terrestrial lichen also had more open canopies which intercepted less snow. Arboreal lichens were used in all forest types; however, arboreal lichen use was greater 1n pine/spruce and spruce stands than in pine stands. Implications of logging to woodland caribou populations and winter range use are discussed and reccrrrnendations for logging guidelines compatible with woodland caribou are suggested. i v TABLE OF CONTENTS PAGE Abstract. i i Table of Contents 1v List of Tables • • • v i List of Figures v i i i Acknowl edgements 1 x Introduction 1 Study area 7 Methods 11 Seasonal movements and habi tat use 11 Winter snow conditions 16 Winter feeding ecology 17 Fecal analyses 19 Results 20 Seasonal movements and habitat use 20 Tweedsmuir-Entiako 20 Itcha-Ilgachuz 29 Rainbow 37 Winter forest cover type use 39 Tweedsmuir-Entiako 39 Itcha-Ilgachuz 42 Winter caribou habitat type use. 45 Tweedsmuir-Enta1ko 45 Itcha-Ilgachuz 49 Winter snow accumulation and sinking depth 55 Winter feeding ecology 59 Cratering versus arboreal lichen feeding 59 Crater selection 62 Terrestrial lichen abundance 62 Canopy cover 65 Snow conditions 67 Fecal fragment analyses and fecal nitrogen 72 D1 scussion 78 Seasonal movements and habitat use 78 Spring migration 78 Calving grounds • • 80 Surrmer range 82 Fall / rutting habitat 82 Winter range 84 Habitat selection on low-elevation winter ranges 85 Terrestrial lichen abundance 85 Forest stand characteristics 86 Seasonal variation 87 Tweedsmui r - Ent i ako 87 Itcha-Ilgachuz 88 V Winter feeding ecology 90 Cratering versus arboreal lichen feeding 90 Crater selection 92 Terrestrial lichen abundance 92 Snow conditions 93 Microsite detection 95 Implications to forestry 95 Surrmer range 96 Winter range 96 Surrrnary 102 Management recarmedations 106 Literature Cited 108 Appendices 115 v1 LIST OF TABLES PAGE 1. Descr ip t ion of Caribou Habitat Types i n the Tweedsmuir-Entiako study area 13 2. Descr ip t ion of Caribou Habitat Types in the I tcha-I lgachuz study area 14 3. Percent of forest cover types ava i l ab le and percent of rad ioco l la red car ibou locat ions in each forest cover type in the Tweedsmuir-Entiako study area during winter (December - March), ear ly winter (December - mid-January), mid winter (mid January - mid March) and l a te w in te r /ear ly spr ing (mid-March - A p r i l ) for 1986/87 and 1987/88 combined 41 4. Percent of forest cover types ava i l ab le and percent of rad ioco l la red car ibou locat ions in each forest cover type in the I tcha-I lgachuz study area during winter (December -March), ear ly winter (December - mid-January), mid winter (mid January - m i d March) and l a te w in te r /ear ly spr ing (mid-March - A p r i l ) for 1986/87 and 1987/88 combined 46 5. Percent of car ibou habi tat types ava i l ab le and percent of rad ioco l la red car ibou locat ions in each car ibou habi tat type in the Tweedsmuir-Entiako study area during winter (December - March), ear ly winter (December - mid-January), mid winter (mid January - mid March) and l a te w in te r /ear l y spr ing (mid-March - A p r i l ) for 1986/87 and 1987/88 combined 50 6. Percent of car ibou habitat type age c lasses ava i l ab le and percent of rad ioco l la red car ibou locat ions in car ibou habi tat type age c lasses 1n the I tcha-I lgachuz study area dur ing winter for 1986/87 and 1987/88 combined 51 7. Percent of car ibou habitat types of age c lass 4-5 ava i l ab le and percent of rad ioco l la red car ibou locat ions 1n each car ibou habi tat type of age c l ass 4-5 i n the I tcha-I lgachuz study area dur ing winter (December -March), ear l y winter (December - mid-January), mid winter (mid January - mid March) and la te w in te r /ear ly spr ing (mid-March - A p r i l ) for 1986/87 and 1987/88 combined 54 8. Percent of feeding s i t e types invest igated (c ra ter ing vs . arboreal l i chen feeding) in the winter ranges of the Tweedsmuir-Entiako and I tcha-I lgachuz car ibou, from January-March 1986, December 1986 - March 1987, December 1987 - March 1988 combined 60 v11 9. Percent of feeding s i t e types invest igated (cra ter ing vs . arboreal l i chen feeding) i n forested habi ta ts i n the winter ranges of the Tweedsmuir-Entiako and I tcha-I lgachuz car ibou, by month, for January-March 1986, December 1986-January 1987 and December 1987-March 1988 combined 61 10. Frequency of occurrence of vegetat ion types in c ra ters (C) and 1n non-crater s i t e s (ACS) on the winter ranges of the Tweedsmuir-Entiako and I tcha-I lgachuz car ibou, from January - March 1986, December 1986 - March 1987, December 1987 - March 1988 combined 63 11. Percentage of c ra ters (C) and non-crater s i t e s (A/CS) found in d i f f e ren t canopy c losure / t e r r e s t r i a l l i chen abundance c lasses i n a l l forested habi tat types combined, i n the Tweedsmuir-Entiako and I tcha-I lgachuz car ibou winter ranges, December 1987 - March 1988 68 v1 i 1 LIST OF FIGURES PAGE 1. L o c a t i o n of the study area i n w e s t - c e n t r a l B r i t i s h Columbia 8 2. Mean e l e v a t i o n of r a d i o c o l l a r e d c a r i b o u l o c a t i o n s (± 1 standard d e v i a t i o n ) i n the Tweedsmuir-Entiako, I t c h a -Ilgachuz and Rainbow areas, 1985/86, 1986/87 and 1987/88 combined 21 3. P r o p o r t i o n of r a d i o c o l l a r e d c a r i b o u l o c a t i o n s 1n each h a b i t a t type i n the Tweedsmuir-Entiako area, 1985/86, 1986/87 and 1987/88 combined , 22 4. R a d i o c o l l a r e d female c a r i b o u l o c a t i o n s i n the Tweedsmuir-Entiako area from November - A p r i l , 1985/86, 1986/87, and 1987/88 23 5. R a d i o c o l l a r e d female c a r i b o u l o c a t i o n s i n the Tweedsmuir-Ent i a k o area from May - October 1985, 1986, 1987 24 6. S p r i n g m i g r a t i o n routes of r a d i o c o l l a r e d female c a r i b o u i n the Tweedsmuir-Entiako area 25 7. F a l l m i g r a t i o n route, and w i n t e r movements of r a d i o c o l l a r e d female c a r i b o u i n the Tweedsmuir-Entiako area 28 8. P r o p o r t i o n of r a d i o c o l l a r e d c a r i b o u l o c a t i o n s 1n each h a b i t a t type i n the I t c h a - I l g a c h u z area, 1985/86, 1986/87 and 1987/88 31 9. R a d i o c o l l a r e d female c a r i b o u l o c a t i o n s i n the I t c h a -Ilgachuz -Rainbow area from November - A p r i l , 1985/86, 1986/87 and 1987/88 32 10. R a d i o c o l l a r e d female c a r i b o u l o c a t i o n s i n the I t c h a -Ilgachuz -Rainbow area from May - October 1985, 1986, 1987 33 11 S p r i n g m i g r a t i o n routes of r a d i o c o l l a r e d female c a r i b o u 1n the Itcha-Ilgachuz-Rainbow area 34 12. F a l l m i g r a t i o n routes of r a d i o c o l l a r e d female c a r i b o u i n the Itcha-Ilgachuz-Rainbow area 36 13. P r o p o r t i o n of r a d i o c o l l a r e d c a r i b o u l o c a t i o n s i n each h a b i t a t type 1n the Rainbow area, 1985/86, 1986/87, and 1987/88 combined 38 1 X 14. Proport ion of forest cover types a v a i l a b l e , and proport ion of rad ioco l la red car ibou locat ions i n each forest cover type dur ing winter (December - March) in the Tweedsmuir-Entiako (N=366), and I tcha-I lgachuz (N=369) winter ranges, December 1986 - March 1988 40 15. Proport ion of forest cover types ava i l ab l e , and proport ion of rad ioco l la red caribou locat ions 1n each forest cover type in the Tweedsmuir-Ent1ako winter range dur ing ear l y winter (N=91), mid winter (N=225), and la te winter (N=89), December 1986 - A p r i l 1988 43 16. Proport ion of forest cover types and proport ion of rad ioco l la red car ibou locat ions 1n each forest cover type in the I tcha-I lgachuz winter range dur ing ear ly winter (N=113), mid winter (N=213), and la te winter (N=63), December 1986 - Ap r i l 1988.. 44 17. Proport ion of car ibou habi tat types and proport ion of rad ioco l la red car ibou locat ions 1n each car ibou habi tat type dur ing winter (December - March), in the Tweedsmuir-Entiako (N=355), and I tcha-I lgachuz (N=321) winter ranges, December 1986 - A p r i l 1988 47 18. Proport ion of car ibou habi tat types and proport ion of rad ioco l la red car ibou locat ions 1n each car ibou habitat type 1n the Tweedsmuir-Entiako winter dur ing ear l y winter (N=97), mid winter (N=221), and l a te winter (N=85), December 1986 - A p r i l 1988 48 19. Proport ion of rad ioco l la red car ibou locat ions in each car ibou habi tat type 1n the I tcha-I lgachuz winter range during ear ly winter (N=100), mid winter (N=178), and l a te winter (N=62), December 1986 - A p r i l 1988 53 20. Mean snow depth at snow s ta t ions 1n 3 habi tat types (wetland, mature and irrrnature pine stands) at Moore Creek, i n the I tcha-I lgachuz winter range, December 1986 - March 1987, December 1987 - March 1988 56 21. Caribou s ink ing depth versus observer s ink ing depth in the Tweedsmuir-Ent1ako and I tcha-I lgachuz winter ranges in 1985/86, 1986/87 and 1987/88 combined (F=39082, p<.05, r 2 . 9 0 ) . 57 22. Predic ted car ibou s ink ing depth at snow s ta t ions i n 3 habi tat types (wetland, mature and Immature pine stands) at Moore Creek, i n the I tcha-I lgachuz winter range, December 1986 - March 1987, December 1987 - March 1988 58 23. Proport ion of c ra te rs (C) and non-crater s i t e s (NCS) conta in ing % ground cover c lasses (0%, 1%, 2-14%, 15-39%,' 40-100%) of t e r r e s t r i a l l i chens (Cladina spp . , Cladonia X spp., Stereocau7on spp. combined) in all forested habitat types combined in the Tweedsmuir-Entiako (C=351, NCS=213), and Itcha-Ilgachuz (C=570, NCS=185) winter ranges (December - March, 1986/87, 1987/88) 64 24. Proportion of craters (C) and non-crater sites (NCS) in % canopy cover classes (<5%, 6-10%, 11-15%, >20% canopy cover) in all forested habitats combined in the Tweedsmuir-Entiako (C=293, NCS=65) and Itcha-Ilgachuz (C=446, NCS=105) winter ranges (December 1986 - March 1987, December 1987 - March 1988) 66 25. Mean snow depths of craters and non-crater sites in all forested habitats combined, during sampling sessions conducted on the Tweedsmuir-Entiako winter range, January - March 1987, January - March 1988 69 26. Mean snow penetrability (weight sinking depth snow depth) of craters and non-crater sites in all forested habitat types combined, during sampling sessions conducted on the Tweedsmuir-Entiako and Itcha-Ilgachuz winter ranges, December 1987 - March 1988 70 27. Mean snow depths of craters and non-crater sites 1n all forested habitat types combined, during sampling sessions conducted on the Itcha-Ilgachuz winter range, December 1986 - March 1987, December 1987 - March 1988 71 28. Percent of vegetation types found in fecal samples collected 1n the Itcha-Ilgachuz area 1n 1985/86. (Samples from April, May and December were collected in 1987) 73 29. Percent fecal nitrogen levels 1n fecal samples collected in the Itcha-Ilgachuz in 1985/86. (Samples from April, May and December were collected in 1987) 75 30. Percent fecal nitrogen levels and percent of vegetation types found in fecal samples collected in the Tweedsmuir-Entiako winter range in 1985/86 and 1986/87 76 31. Percent fecal nitrogen levels and percent of vegetation types found in fecal samples collected in the Itcha-Ilgachuz winter range in 1985/86 and 1986/87 77 xi ACKNCWLEDGEMENTS Due to the nature of this project, many people were involved in securing funding, and assisting with various aspects of fieldwork. I regret that I do not have room to mention everyone involved, and apologize to those I have missed. I would l i k e to thank the members of my advisory corrmlttee, Dr. Fred Bunnell, Dr. A.R.E. Sinclair and especially Dr. Dale Seip, my research supervisor, for their advice and direction. The members of the West-Central B r i t i s h Columbia Caribou Research Project Corrmittee also provided direction and were instrumental in securing funding for the project. Major funding was provided by: the Br i t i s h Columbia Ministry of Forests, in part through Section 88 credits to Fraser Lake Sawmills, Jacobson Brothers Forest Products Ltd., L & M Lumber Ltd., Lignum Ltd., and Westar Timber; the B r i t i s h Columbia Ministry of Parks; the B r i t i s h Columbia Ministry of Environment, Fish and W i l d l i f e Branch (Williams Lake, Smithers); the National Science and Engineering Council of Canada (graduate scholarship); the Science Council of B r i t i s h Columbia; and the World Wildlife Fund. Additional financial assistance was provided by: the Faculty of Forestry, University of Br i t i s h Columbia; the Tweedsmulr Rod and Gun Club; Fraser Lake Sawmills; and the University of Br i t i s h Columbia Scholarship Fund. Special thanks go to everyone who contributed to the success of the fieldwork. Floyd Vaughan and Wayne Escott s k i l l f u l l y and safely piloted aircraft during radiotelemetry f l i g h t s . Roy Mulvahlll, Rick Marshall and Wayne Escott proved invaluable during winter groundwork. Tom Smith, Dave Hatler, pi l o t s Tom Arduini and Tom Brooks, and Rick Marshall and members of the Tweedsmuir Rod and Gun Club captured and radiocollared caribou. Daryll Hebert provided valuable l o g i s t i c support and advice, and Jim Pojar was instrumental 1n i n i t i a t i n g the Caribou Habitat Mapping project. Finally, I would like to thank Mary Ratzlaff and Nick Christlanson 1n Nimpo Lake, and Roy and Gwen Mulvahlll in Chezacut, for providing me with two 'homes away from home', and Laura Vaughan for her hospitality after radiotelemetry f l i g h t s . Also, thanks to a l l who made my stay in the Chi 1 cotin enjoyable and memorable. 1 INTRODUCTION Decreasing woodland car ibou (Rangifer tarandus caribou) numbers (Bergerud 1974a, 1978) and increas ing Togging a c t i v i t y on car ibou ranges p rec ip i ta ted the need for a bet ter understanding of re la t i ons between car ibou and the i r habi tat 1n B r i t i s h Colunbla. In B r i t i s h Columbia, two 'ecotypes' of woodland car ibou are d is t ingu ished by the i r winter habitat use and foraging s t ra teg ies (Stevenson and Hat ler 1985). 'Mountain' car ibou are found in southeastern B.C. where snow accumulation i s h igh. In winter these car ibou inhabit high e levat ion subalpine fo res ts and feed on arboreal l i chens . 'Northern ' car ibou are found in west-central and northern B r i t i s h Columbia where snow accumulation 1s low. In winter , these car ibou inhabi t low e levat ion forested areas or windswept a lp ine s lopes, and feed p r imar i l y by digging through the snow to obtain t e r r e s t r i a l forages, mainly l i chens . Studies conducted on 'mountain' car ibou in southeastern B r i t i s h Columbia demonstrated the importance of mature subalpine fo res ts and arboreal l i chens dur ing winter (Ant i feau 1987, Seip 1988, Servheen and Lyons 1989, Simpson et a l . 1987). Relat ions between 'nor thern ' car ibou and winter habi tat were invest igated i n northern B r i t i s h Columbia where low e levat ion forested habi ta ts were heav i ly used and car ibou fed p r imar i l y on t e r r e s t r i a l l i chens (Hatler 1986). In west-central B r i t i s h Columbia, two populat ions of 'nor thern ' woodland car ibou e x i s t : the Tweedsmuir-Entiako populat ion which cons is ts 2 of about 500 caribou, and the Itcha-Ilgachuz-Rainbow population which consists of about 1500 caribou. Portions of the winter ranges of these populations were scheduled for logging; l i t t l e information however, was available for developing logging guide!ines compatible with caribou winter habitat use. Incidental observations in the Itcha-Ilgachuz-Rainbow area suggested that at low elevations, caribou foraged 1n open areas and used forests for security or thermal cover. Relative importance of terrestrial lichens, arboreal lichens, and grasses and sedges in the winter diet was unknown. Arboreal lichen use on low elevation winter ranges was believed to increase as snow conditions limited use of terrestrial forages. In addition to low elevation forested areas, caribou also were observed on alpine slopes in the northern Ilgachuz and Rainbow Mountains; however, the relative importance of alpine and low elevation areas as winter habitat was unknown. In Tweedsmuir-Ent1ako, observations indicated that caribou foraged for terrestrial lichens in forested areas (Marshall 1985). Information obtained from southeastern and northern British Columbia could not be extrapolated to west-central B.C. because of disparate environmental features (topography, climate, vegetation). Therefore, this study of radiocollared caribou was initiated in the Tweedsmuir-Ent1ako and Itcha-Ilgachuz-Rainbow areas to collect information on caribou-habitat relationships. To understand the relations between caribou and their habitat, 1t 1s important to understand the relations between caribou and different levels of resource selection. Interactions between animals and their 3 environment occur at four levels within a hierarchy of resource selection (Johnson 1980): 1) Geographic range of the species 2) Seasonal movements and home range (Includes habitat use) 3) Feeding site selection 4) Diet selection. The geographic range of woodland caribou has been described elsewhere (Banfield 1961) and was not directly relevant to the present study. This study focussed on second, third, and fourth order selection. The objective of the study was to determine seasonal movements, habitat use and food habits of caribou in the Itcha-Ilgachuz-Rainbow and Tweedsmuir-Entiako areas, especially during winter. Seasonal movements and habitat use defined second order resource selection. Regular monitoring of radiocollared caribou was required to determine seasonal movement patterns and home ranges. Third order resource selection was determined by examining parameters associated with selection of winter feeding sites and fourth order selection (food habits) was inferred from feeding sites and fecal samples. This information was necessary to develop logging guidelines compatible with caribou winter habitat use. During the first year of study (April 1985 - March 1986) preliminary data on habitat use and feeding sites were collected. These data indicated that in winter, caribou used primarily mature lodgepole pine (Pinus contorta) forests and in these pine forests they foraged for terrestrial lichens (Cichowskl 1986). No evidence of foraging was found in open areas and arboreal lichen feeding appeared to be minimal. As 4 part of this project, the British Columbia Ministry of Forests developed Caribou Habitat Unit maps for the Tweedsmuir-Entiako and Itcha-Ilgachuz winter ranges, with habitat units based on terrestrial lichen abundance (B.C.M.O.F. 1987a, B.C.M.O.F. 1987b). The preliminary information on habitat use and foraging habits was used to formulate hypotheses for selection of winter habitat types and feeding sites by caribou. H1: During the winter months, caribou select forest stands containing abundant terrestrial lichens and avoid stands where lichens are uncorrrnon. Terrestrial lichens are poor competitors against vascular plants; they are most abundant on nutrient-poor, dry, open sites where competition from vascular plants is minimal or nonexistent (Hale 1983, Johnson 1981, Kershaw 1977, Rowe 1984). Because terrestrial lichens grow on poor quality growing sites, trees growing on sites with abundant lichens are usually slow growing and of poor quality and low merchantable value. Lichens also have slow growth rates and are associated with late successional stages (Carroll and Bliss 1982, Hale 1983, Klein 1982). Mature pine stands contain greater amounts of terrestrial lichens than immature stands (Clement 1987) and are considered important winter habitats for caribou. 5 H2: During the winter months, caribou select mature timber types on poor quality forest growing sites and avoid inrmature stands and good growing sites. Hypotheses 1 and 2 examined second order resource selection and were tested by determining habitat types (caribou habitat types (H1) and forest cover types (H2)) most frequently used by caribou, and comparing habitat use to habitat availability. Snow conditions could also have an effect on caribou selection of habitat types during winter. In non-forested areas, snow accumulation may impede caribou movements and cratering. In forested areas, snow interception by coniferous trees should result in less snow accumulation than in unforested areas, making locomotion and cratering easier in the forested areas. Snow depth was measured over the winter in open habitat, and 1n immature pine and mature pine stands to determine whether snow conditions differed between the 3 habitat types, thus potentially affecting habitat use (second order selection) by caribou. Selection of feeding sites (third order selection), depends on microhabitat characteristics within each habitat type. On treeless Arctic ranges, barren-ground caribou crater where snow depth and hardness are relatively low (Adamczewski et al. 1988, Duquette 1988, Henshaw 1968, LaperMere and Lent 1977, Miller 1976, Pruitt 1959, Russell and Martell 1984). Within forested winter ranges, woodland caribou in southeastern Manitoba and west-central Alberta selected crater sites based on terrestrial lichen availability and snow 6 condi t ions (Darby and P ru i t t 1984, Edmonds and Bloomfield 1984). From t h i s informat ion, hypotheses on t h i r d order se lec t i on by woodland car ibou in west-central B.C. were formulated. H3: Caribou crater i n areas where t e r r e s t r i a l l ichens are ava i l ab le and abundant, and avoid c ra te r ing where t e r r e s t r i a l l i chens are absent or present in low quan t i t i es . H4: Caribou crater i n areas where snow condi t ions (snow depth, snow pene t rab i l i t y ) a l low eas ier d igging and locomotion ( i . e . , shallow snow packs, greater snow p e n e t r a b i l i t y ) . Hypotheses 3 and 4 were tested by comparing snow condi t ions and l i chen cover at feeding c ra te rs used by car ibou, to snow condi t ions and l i chen cover at non-crater s i t e s which I excavated in areas where car ibou walked without c ra te r i ng . Fourth order resource use (food items) was determined through examination of feeding c ra te rs i n winter and proport ion of food items found in feca l samples co l l ec ted throughout the year. Potent ia l e f fec ts of logging on car ibou populat ions were examined, and management reconrrnendations for logging p rac t i ces compatible with car ibou winter habitat use in west-central B r i t i s h Columbia were proposed, based on information obtained on second, t h i r d and four th order resource se lec t i on by woodland car ibou. 7 STUDY AREA The study area was located 1n the western part of centra l B r i t i s h Columbia (F1g.1), almost e n t i r e l y w i th in the In te r io r Plateau physiographic region (Holland 1976). The southern sec t ion of the study area extended from the Rainbow Mountains 1n Tweedsmuir Park, east to 20 ki lometers east of the C h l l c o t i n R iver , and northeast to the Blackwater R iver . Most of t h i s area l i e s between 1200 and 1650 meters on the Fraser Plateau region of the In te r io r P la teau. Three dome-shaped sh ie l d volcanos r i s e from the f l a t or gent ly r o l l i n g upland, up to 2350 meters in the I tcha Mountains, 2400 meters in the Ilgachuz Mountains and 2475 meters in the Rainbow Mountains (Holland 1976). This southern part of the study area consis ted predominantly of the Very Dry Central Montane Spruce b iogeocl imat ic subzone (MSd) (B.C.M.O.F. 1989a). The Sub-Boreal Pine-Spruce (SBPS) zone occurred at lower e levat ions (<1300 - 1500 meters) and the Engelmann Spruce Subalpine F i r zone (ESSF) occurred at higher e levat ions (>1650m) (B.C.M.O.F. 1989b). A lp ine tundra was present i n the I tcha, I lgachuz and Rainbow Mountains above the ESSF. The MSd and SBPS were dominated by lodgepole pine (Pinus contorts) stands. In te r io r spruce (Picea glauca X engelmannii) occurred adjacent to wetland s i t e s 1n pure stands or i n mixed pine/spruce stands. The shrub layer was l im i ted p r imar i l y to soapberry (Shepherdia canadensis); ground cover and herb layer consis ted of mosses, t e r r e s t r i a l l ichens (Cladina spp . , Cladoma spp. Stereocaulon spp . , Peltigera spp.) and k inn ik inn ick (Arctostaphylos uva-ursi). Large dry, g rass - l i chen (fescue-1 ichen) meadows were present i n areas of co ld a i r ponding and wet sedge fens and shrub-carrs occurred along drainages and i n areas Fig. l . Locat ion of the study a r e a in wes t - cen t ra l British Columbia 9 where the watertable was at or near the surface (Clement 1987). Festuca altaica was the dominant grass in fescue-1ichen meadows, and scrub birch (Betula glandulosa) and willows (Salix spp.) were associated with shrub-car rs and interfaces between open areas and forest stands. Lodgepole pine, interior spruce and subalpine f i r (Abies lasiocarpa) were the major components of stands in the ESSF. Arboreal lichens, almost exclusively Bryonia spp., were found in all stand types. The alpine tundra zone was dominated by dry alpine ccrnnunities such as alpine grasslands and dwarf scrub. Vegetation consisted of terrestrial lichens, grasses, and dwarf scrub (Cassiope spp., Arctostaphylos uva-ursi, Phy 7 lodoce spp., Empetrum nigrum, Vacciniun spp., Dryas spp., Sa77'xspp., Betula glanduTosa) (Pojar 1983). The northern part of the study area extended from the area in and to the west of northern Tweedsmuir Park, east and southeast to the Fawnie Mountains and to the Blackwater River. Most of this area lies on the Nechako Plateau region of the Interior Plateau; however, the westernmost part of Tweedsmuir Park and the area to the west are part of the Coast Mountains physiographic region (Holland 1976). The Coast Mountains adjacent to northern Tweedsmuir Park are typically round-topped mountains with peaks ranging from 2000-2300 meters. Rivers transecting the ranges result in relief of 1500-2000 meters. The Nechako Plateau lies between 850 and 1300 meters and is characterized by flat or gently rolling terrain. The round topped Quanchus Mountains and Fawnie Mountains rise up from the Nechako Plateau to 2250 meters and 1920 meters respectively. Most of the Nechako Plateau consisted of the Sub-Boreal Spruce (SBS) and SBPS biogeoclimatic zones (Lewis et al. 10 1986). The ESSF zone occurred at higher elevations (>1200m) and alpine tundra occurred above the ESSF in the Fawnie Mountains and in the mountains of northern Tweedsmuir Park. Lower elevation forested areas consisted of lodgepole pine or mixed lodgepole pine/spruce stands. Spruce also occurred in bands along lakes and wetlands as well as in wetlands (forested wetlands). Lakes and sedge fens were corrmon and often occurred in mosaics of lakes, fens, and fringe forests of spruce. Shrubs and ground cover were similar to that of the Itcha-Ilgachuz-Rainbow area but included a greater variety of species. Arboreal lichens occurred throughout the forested area but were especially abundant in forested wetlands and spruce fringes surrounding lakes and fens. The western part of northern Tweedsmuir Park and the area to the west, consisted of the Coastal Western Hemlock (CWH) biogeoclimatic zone at low elevations, and the Mountain Hemlock (MH) or the ESSF zones at higher elevations below the alpine tundra zone. Forest stands in this area were generally mixed stands of amabalis f i r (Abies amabalis), western red cedar (Thuja piicata), hemlock (Tsuga spp.), spruce (Picea spp.) and Douglas-fir (Pseudotsuga menziesii). Alpine tundra in the Quanchus Mountains and Fawnie Mountains was dominated by dry alpine comnunities. In western Tweedsmuir Park and the Coast Mountains, the alpine tundra zone was dominated by moister dwarf scrub and herb meadow corrmunities (Pojar 1983). Most of the study area lies within the rainshadow of the Coast Mountains and is characterized by a dry continental climate. Surrmers are typically cool, short, and dry, and winters are very cold, long, and dry. The weather station at Tautri Lake, 40 km southeast of the study 11 area (SBPS biogeoclimatlc zone, 1200 meters above sea level) reports mean annual precipitation and winter snow accumulation of 420 rrm and 50 cm respectively (Annas and Coupe 1979). Soils throughout the winter ranges are predominantly Brunisolic Gray Luvisols and Dystrlc Brunisols on moralnal deposits (B.C.M.O.F. 1989a,1989b, Lewis et al. 1986). METHODS SEASONAL MOVEMENTS AND HABITAT USE A total of 52 adult female caribou (Tweedsmuir-Entiako-25, Itcha-Ilgachuz -Rainbows -27) were radiocollared and tracked during the three year study (April 1985 - March 1988). Caribou were caught using 3 methods of capture. In the Itcha-Ilgachuz-Rainbow area, caribou were captured during late fall (October-November) or late winter (March-April) in open areas (alpine, meadows) and were either netgunned from a helicopter or herded by a helicopter into drive nets. In the Tweedsmuir-Entiako area, caribou were caught from boats as they were crossing Tetachuck Lake during fall migration in November 1983 and November 1984 (Marshall 1984). In February 1987, caribou in alpine habitat 1n the Fawnie Mountains were netgunned from a helicopter. Radiocollared caribou were located by telemetry from aircraft approximately biweekly from April to November and weekly from December to March. Locations were plotted onto 1:100 000 scale map sheets and habitat, aspect and elevation of each location were recorded. 12 Coordinates of each location were recorded to the nearest 0.5 kilometer and plotted by the HOME program on UBC MTS (Harestad 1981). Winter locations were also plotted onto 1:50 000 scale B.C. Forest Service forest cover maps and caribou habitat maps (B.C.M.O.F. 1987a, 1987b). Locations that were not plotted directly onto forest cover maps or caribou habitat maps after each telemetry flight were not used in the analyses. Therefore, locations from winter 1985/86 were not used. Forest cover types were grouped according to dominant tree species present. Each group was divided into immature (age classes 1-4, 0-80 years) and mature (age classes 5-9, >80 years) age classes and further divided Into low, poor and medium quality site types. Low quality sites are lower quality growing sites than poor sites, which 1n turn are lower than medium sites. Availability of each forest cover type 1n the Itcha-Ilgachuz winter range was determined by plotting 1449 random points onto forest cover maps of the study area and calculating the proportion of the total random points occurring in each forest cover type. A 95% confidence interval was calculated for each forest cover type available using the Bonferroni z statistic (Neu et al. 1974). Availability of forest cover types in the Tweedsmuir-Entiako winter range was determined as a proportion of the total area using the B.C. Ministry of Forests GECMAP database. Caribou habitat type polygons (individually labelled map units) were grouped according to abundance of terrestrial lichens as described in Tables 1 and 2. A more detailed description of individual habitat 13 Table 1. Descr ip t ion of Caribou Habitat Types 1n the Tweedsmuir-Entiako study area. Caribou Habi tat Tvpe DLLM LM DLLM MOSAIC MDLLM MSF/AF W/FW Descr ip t ion and associated polygon un i ts Dry Lichen / Lichen Moss - inc ludes dry l i chen / l i chen moss combinations and dry l i chen leading and dominant over moss DL, DL/LM, DL//LM, LM/DL, LM//DL, DL/ /M, DL/M Lichen Moss - l i chen moss leading and dominant over moss LM, LM//M, LM/M Dry Lichen / Lichen Moss Ecomosaic -combinations of dry l i chen or l i chen moss with adjacent wetlands or seepage fo res ts DL/SF, DL/W, W/DL, SF/DL, DL / /SF , DL//W, W//DL, SF//DL LM/SF, LM/W, W/LM, SF/LM, LM//SF, LM//W, W//LM, SF//LM Moss - Dry Lichen / Lichen Moss -moss leading and dominant over dry l i chen or l i chen moss; includes dry l i chen or l i chen moss as a 3rd uni t with combinations of moss and seepage forest as the f i r s t 2 un i ts M//DL, M//LM, M/DL, M/UVI, M/SF/DL, Ml/SF/DL, M/SF//DL, M/ /SF/ /DL, SF/M/DL, SF/ /M/DL, SF/M//DL, SF / /M/ /DL , M/SF/LM, M//SF/LM, M/SF//LM, M/ /SF/ /LM, SF/M/LM, SF/ /M/LM, SF/M/ /LM, SF/ /M/ /LM Moss / Seepage Forest - Aspen Forest combinations -combinations of moss and seepage forest and aspen forest without dry l i chen or l i chen moss as the 3rd un i t ; aspen forest leading or dominant over any other habi tat M, M/SF, M/AF, M/ /SF, M//AF, SF, SF/M, SF/AF, SF / /M , S F / / A F , A F / / , AF/ Wetlands / Moss - Seepage Forest Wetlands -wetlands; includes wetlands with f r inge fo res ts of moss or seepage forest W, W//M, W//SF, W//AF, W/M, W/SF, W/AF, M/W, SF/W, M//W, SF / /W LAKE Lake Symbols A/B A leading over B (Amount of A = amount of B, i n polygon) A / / B A dominant over B (Amount of A > amount of B, 1n polygon) W = Nonforested wetland (NW) or Forested wetland (FW) 14 Table 2. Descr ip t ion of Caribou Habitat Types in the I tcha-I lgachuz study area. Caribou Habi tat Type DLLM LM Descr ip t ion and associated polygon un i ts Dry Lichen / Lichen Moss combinations DL, DL/LM, DL//LM, LM/DL, LM//DL Lichen Moss - l i chen moss pure and l i chen moss dominant over moss LM, LM//M DLLM MOSAIC MDLLM MSF W/FW FL Dry Lichen / Lichen Moss Ecomosalc -combinations of dry l i chen or l i chen moss with adjacent wetlands or seepage fo res ts DL/SF, DL/W, W/DL, SF/DL, DL/ /SF, DL//W, W//DL, SF//DL LM/SF, LM/W, W/LM, SF/LM, LM//SF, LM//W, W//LM, SF//LM Moss / Dry Lichen / Lichen Moss - l i chen moss, dry l i chen , moss, leading but not dominant DL/M, M/DL, LM/M, M/LM Moss / Seepage Forest combinations - inc ludes moss dominant over l i chen moss and dry l i chen M, M/SF, M/ /SF, SF, SF/M, SF / /M , M//DL, M//LM Wetlands / Forested Wetlands - inc ludes wetlands with f r inge fo res ts of seepage forest or moss W, W//M, W/ /SF, W/M, W/SF, M/W, SF/W, M//W, SF / /W Fescue Lichen meadows - inc ludes fescue-11chen meadows with f r inge fo res ts of dry l i chen or l i chen moss and fescue-1ichen / wetland combinations FL, FL//W, FL/W, W//FL, W/FL, FL / /DL , FL / /LM, FL/DL, FL/LM SBPS-DLK SBPS-OTHER SBPSxc - Dry Lichen / K1nn1k1nn1ck combinations - inc ludes dry l i chen and k inn ik inn ick dominant over other SBPSxc un i ts DL, DL/K, DL/ /K, K, K/DL, K/ /DL, DL/ /R, DL/ /M, SBPSxc - un i ts other than SBPS-DLK un i ts Symbols A/B A leading over B (Amount of A = amount of B, 1n polygon) A / / B A dominant over B (Amount of A > amount of B, i n polygon) 15 units can be obtained from the B.C. Ministry of Forests (Williams Lake; Smithers). In general, in the SBPSmc (previously SBSa2), SBS and MSd, dry lichen (DL) sites contained the most terrestrial lichen. Lichen moss (LM) sites contained less terrestrial lichen and more moss than DL sites. Moss (M), seepage forest (SF) and aspen forest (AF) sites contained very l i t t l e or no terrestrial lichen. All forested habitat types contained arboreal lichens but moister types (M,SF) appeared to contained larger quantities of arboreal lichens than drier types (DL,LM). Wetlands (W), non-forested wetlands (NW), and forested wetlands (FW) were wet, generally open areas containing primarily grasses, sedges and shrubs. Fescue-lichen (FL) meadows were dry open areas containing grasses (primarily Festuca altaica) and terrestrial lichens. In the SBPSxc (previously SBSal), dry lichen and kinnlkinnlck (K) sites contained the most terrestrial lichen. All other habitat types in the SBPSxc contained l i t t l e terrestrial lichen. Each group was divided into irrmature (age classes 1-3, 0-80 years) and mature (age classes 4-5, > 80 years) age classes. Availability of each caribou habitat type in the Tweedsmuir-Entiako winter range was determined as a proportion of the total area using the Ministry of Forests GEOMAP database. Availability of each caribou habitat type in the Itcha-Ilgachuz winter range was determined by plotting 1932 random points onto caribou habitat maps of the study area and following the procedure used for determining forest cover type availability. Caribou use of forest cover types and caribou habitat types was calculated as the proportion of radiocollared caribou locations in each type for winter (December - March), early winter (December - mid-16 January), mid winter (mid-January - mid-March) and late winter/early spring (mid-March - April). Differences between the pattern of caribou use, and availability of forest cover types and caribou habitat types, were tested by the chi-squared technique (Neu et al. 1974) at a=.05. Differences between caribou use and the availability of individual forest cover types and caribou habitat types were tested by using the Bonferroni z statistic (Neu et al. 1974) to calculate 95% confidence intervals (winter) or 90% confidence intervals (early winter, mid winter, late winter/early spring) for caribou use of each habitat type. A surmary of all altitudinal movements, habitat use, forest cover type use and caribou habitat type use data for each area by year and season is presented in appendix I. WINTER SNOW CONDITIONS Snow stations were set up in the Itcha-Ilgachuz caribou winter range near Moore Creek (10 kilometers east of the Chilcotin River; 1500 meters above sea level; MSd biogeoclimatic subzone) during the winters of 1986/87 and 1987/88. Snow depth, observer sinking depth, and snow penetrability (1987/88 only) were measured biweekly from December to March in 3 habitat types (mature pine, Irrmature pine, meadow). Snow penetrability was measured as the distance that a 1 kilogram weight penetrated the snowpack after being dropped from a height of 1 meter above the snow; divided by the snow depth at the site. A total of 30 measurements were taken in each habitat type; 5 measurements, at 6 stations, which were 25 meters apart. 17 When very f resh car ibou t racks were encountered, car ibou s ink ing depth, observer s ink ing depth and snow depth irrrnediately adjacent to the caribou track were measured. Caribou s ink ing depth was regressed against observer s ink ing depth and the equation from the regression was then appl ied to the mean observer s ink ing depth at the snow s ta t ions to predic t car ibou s ink ing depths i n a l l 3 habi tat types over the winter . WINTER FEEDING ECOLOGY During the winter months, feeding s i t e s of car ibou in forested areas were inves t iga ted . The winter range of each car ibou populat ion was v i s i t e d by snowmobile biweekly fo l lowing radiotelemetry f l i g h t s . When f resh car ibou t racks were encountered in areas being used by rad ioco l la red car ibou, t racks were fol lowed or backtracked to locate feeding s i t e s . Very f resh t racks were backtracked to avoid d i sp lac ing the car ibou. Feeding s i t e type (c ra te r ing , arboreal l i chen feeding, browsing) was noted at each feeding s i t e , and the proport ion of c ra te r ing s i t e s versus arboreal l i chen feeding s i t e s was ca lcu la ted for each habi tat type. The proport ion of c ra te r ing and arboreal l i chen feeding in a l l forest types combined (pine, spruce and p ine/spruce) , was ca lcu la ted by weighting the amounts of each feeding type i n each forest type by the proport ion of telemetry locat ions in each forest type. # locat ions in forested # c ra te rs in habitat x habitat x x (or arboreal l i chen s i t es ) # locat ions in a l l forested to ta l # feeding s i t e s habi tat types combined i n habi tat x 18 The weighted proport ions were then added to determine the ove ra l l proport ion of c ra te rs and arboreal l i chen feeding s i t e s in a l l forested habi ta ts combined. In the winter of 1985/86, vegetat ion present at each crater was i d e n t i f i e d . During the winters of 1986/87 and 1987/88, c ra ter s i t e s (C) were compared to p i t s dug at 100 step i n te rva l s where car ibou were walking but not c ra te r ing (non-crater s i t e s (NCS)). Snow condi t ions (snow depth, snow pene t rab i l i t y (1987/88 on l y ) ) , canopy c losure (1987/88 only) and presence and % ground cover of vegetat ion present were measured at each cra ter and non-crater s i t e . Percent ground cover of vegetat ion types was grouped in to 5 c l asses ; absent (0%), t race (<1%), low (2-14%), medium (15-39%) and high (>40%). Canopy cover in an area 10 meters 1n diameter around the cra ter was v i s u a l l y estimated as very open (<5% canopy cover) , open (6-10%), moderately open (11-15%), moderately open - moderately c losed (16-20%) and moderately c losed (>20%). A chi-squared contingency tab le was used to test the d i f fe rence between the proport ion of c ra te rs that contained t e r r e s t r i a l l i chens and the proport ion of non-crater s i t e s that contained t e r r e s t r i a l l i chens at a=.05 (Mendenhall 1983). Di f ferences between d i s t r i b u t i o n of percent t e r r e s t r i a l l i chen cover c lasses in c ra te rs and in non-crater s i t e s , and d i f fe rences between d i s t r i b u t i o n of percent canopy cover c lasses at c ra te rs and at non-crater s i t e s were a lso tested using the chi-squared technique at a=.05. 19 Dif ferences between mean snow depth at c ra ters and mean snow depth at non-crater s i t e s , and mean d i f fe rences between snow pene t rab i l i t y at c ra te rs and mean snow pene t rab i l i t y at non-crater s i t e s , were tested using pai red t - t e s t s for each sampling session at a=.05 (Mendenhall 1983). FECAL ANALYSES Indices of forage u t i l i z a t i o n and food qua l i t y were determined through analyses of feca l p e l l e t groups. Fecal samples were co l l ec ted monthly during the winter (December-March) for each area and oppo r tun i s t i ca l l y dur ing the rest of the year. General trends 1n forage u t i l i z a t i o n were determined through feca l fragment ana lys is (Davitt and Nelson 1980). P e l l e t s from 10 feca l samples co l l ec ted dur ing each sampling session were pooled and sent to the W i l d l i f e Habitat Laboratory, Washington State Un ivers i t y for ana l ys i s . Percent feca l n i t rogen for each of 10 samples co l l ec ted dur ing each sampling session were analyzed using the microkjeldhal technique by the Facul ty of Ag r i cu l tu re , UBC (A.O.A.C. 1984). Annual pat terns of forage u t i l i z a t i o n and percent feca l n i t rogen were based on feca l samples co l l ec ted in 1985/86 in the I tcha-I lgachuz-Rainbow study area. Because feca l samples were co l l ec ted oppo r tun i s t i ca l l y during spr ing , surmer and f a l l , 1985/86 samples were supplemented with samples from A p r i l , May and December 1987 to demonstrate seasonal trends. 20 RESULTS SEASONAL MOVEMENTS AND HABITAT USE Seasonal movements and habitat use are described for Tweedsmuir-Entiako, Itcha-Ilgachuz, and Rainbow caribou separately. These three groupings were based on use of different calving grounds by the caribou. Tweedsmu i r-Ent i ako Tweedsmuir-Entiako caribou were found predominantly in low elevation forested habitat in the Entiako Lake area during winter, and moved northwest across Tetachuck Lake to calve, and to spend the surrmer in northern Tweedsmuir Park and in the mountains west of the park. In April, radiocollared caribou were found primarily 1n low elevation pine and pine/spruce forests on the south side of Tetachuck Lake (Figs.2,3,4). By early May, all radiocollared caribou had moved north across Tetachuck Lake (Fig.5). During migration from winter to surrmer ranges, about 85% of the radiocollared caribou were found in low elevation forested habitats along the Chelaslie River drainage (F1g.6). Those caribou moved through the Quanchus Mountains at low elevations in the Glatheli Lake and Fenton Lake areas enroute to calving areas to the west and southwest near Tahtsa Lake, Whitesail Lake, Eutsuk Lake and the Gamsby River (Fig.5). About 15% of the radiocollared caribou moved along the north shore of Eutsuk Lake enroute to calving areas near the west end of Eutsuk Lake. 21 2200-1 2000 1800 1600-1400-^ 1200 D % 1000-Ui 800 600 in v_ «) c o Tweedsmuir-Entiako APR MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB MAR 2200 2000 in J> 'BOO | 1600 c 1400 O U= 1200 o © 1000 UJ 800 600 Itcha-Ilgachuz APR MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB MAR 2200 2000 In jjj 1800 | 1600 ^ 1400 o ^ 1200-D J D 1000-Ul 800-600-Rainbow APR MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB MAR F i g . 2 . Mean e l e v a t i o n of r a d i o c o l l a r e d c a r i b o u l o c a t i o n s (± 1 standard d e v i a t i o n ) i n the Tweedsmuir-Entiako, I t c h a - I l g a c h u z and Rainbow areas, A p r i l - March, 1985/86, 1986/87 and 1987/88 combined. Upper l i n e s represent c a r i b o u u s i n g a l p i n e / s u b a l p i n e h a b i t a t ; lower l i n e s represent c a r i b o u u s i n g lower e l e v a t i o n h a b i t a t . TWEEDSMUIR-ENTIAKO 100-1 C o -f— o o _o • o o o T J CD O o o O c O Q_ rz3 Lake • Alpine Subalpine Fir / Spruce/Pine ZU Meadow K 2 P ine /Spruce / Meadow •DD Spruce/Meadow Pine/Meadow E H Pine/Spruce Spruce Pine Mountain Hemlock Zone Coastal Western Hemlock Zone A p r i l -May J u n e -July D e c -March F i g . 3 . Proport ion of rad ioco l la red caribou locat ions in each habi tat type in the Tweedsmuir-Entiako area, 1985/86, 1986/87 and 1987/88 combined. (N) = number of l oca t ions . ro ro Fig.4 . Rad ioco l la red female c a r i b o u locations in the Tweedsmu i r -En t i ako a r e a from N o v e m b e r - A p r i l , 1985 /86 , 1 9 8 6 / 8 7 , a n d 1987/88 combin ed . ro to O u n * ca l f survey) (Oc lobar rut lurvey) Fig .5 . Rad ioco l l a red female c a r i b o u -bea t comb ined . ions in the Tweedsmu i r -En t iako a r e a from M a y - O c t o b e r . 1985. 1986 and" 1987 ro 26 During calving and early sunrrner (June-July), about 40% of the radiocollared caribou cows were found in alpine or subalpine habitat. These caribou were found mostly in the Chikamln Mountains, the mountains to the west and northwest of the Tweedsmuir Park boundary, and the mountains at the west end of Eutsuk Lake. Few caribou calved in the alpine or subalpine in the Quanchus Mountains. The other radiocollared caribou were found throughout northern Tweedsmuir Park (northeast of Eutsuk Lake) in low elevation forested habitat types. From July to September, caribou were widely distributed throughout the park and used a wide variety of habitats ranging from Coastal Western Hemlock forests at 500 meters to alpine habitat at 2000 meters. Movements during the sifrmer and early fall consisted primarily of movements from high elevation alpine/subalpine habitat to lower elevation forested habitat. In August and September, over 80% of all radiocollared caribou locations were in low elevation forested areas. By October, movements increased as up to 50% of the radiocollared caribou moved to rutting areas in the Quanchus Mountains. Almost half of the radiocollared caribou locations in October and early November were 1n alpine and subalpine habitat in the Quanchus Mountains. In addition, up to 20% of the radiocollared caribou used meadow and forested/meadow complexes east of the Quanchus Mountains. Other radiocollared caribou cows were found throughout the park in lower elevation forested habitat on the north side of Tetachuck Lake during the rut 1n October, and prior to crossing the lake in mid-November . 27 By late November, almost all radiocollared animals had moved south across Tetachuck Lake to the Entiako Lake area (F1g.4). The only exception occurred during the winter of 1987/88 when one radiocollared caribou remained in the Eutsuk peak area until mid-January, before moving south across Tetachuck Lake. During fall migration caribou did not appear to use specific crossing areas on Tetachuck Lake, but rather crossed anywhere along the lake (Fig.7). Between early December and mid-February, caribou were distributed primarily throughout the Entiako River drainage. Some animals were also found near Laidman Lake, Moose Lake, and Tsacha Lake. During this time, almost 80% of the locations occurred 1n low elevation pine or pine/spruce forests (F1g.3). By late February up to 25% of the radiocollared caribou had moved into alpine habitat in the Fawnie Mountains. Use of alpine areas during late winter was variable during the 3 year study. In 1985/86 and 1986/87, 1 out of 12, and 3 out of 11 radiocollared caribou respectively were found 1n alpine areas 1n the Fawnie Mountains. In 1987/88 however, none of the 14 radiocollared caribou used alpine habitat any time during the winter. Caribou sign was absent altogether from alpine areas in the Fawnie Mountains 1n 1987/88. Alpine habitat was used until mid-late March. In mid-March, radiocollared caribou concentrated at the mouth of the Entiako River and in the area to the east in pine/spruce and pine forests. Caribou exhibited a definite shift from the Entiako Lake area in early and mid-winter to the area near the mouth of the Entiako River in late winter (Fig.7). By late March caribou had moved to the south side of Tetachuck Lake before crossing the lake and migrating to surmer range. ig ra t ion route a n d w in te r movements of r a d i o c o l l a r e d female ca r i bou in the Tweedsmui r -Ent iako ro 29 Some small groups of caribou did not undergo movements made by radiocollared caribou from sunrrner range in northern Tweedsmuir Park to winter range south of Tetachuck Lake. A band of 10-20 caribou was reported to have spent the winter 1n northern Tweedsmuir Park along the south shore of Ootsa Lake 1n 1986/87 (Rick Marshall pers. corrrn.). Also, caribou were seen during surrmer and fall months south of Tetachuck Lake in the Moose Lake area (John Blackwell pers. corrm.). Although some caribou are found north of Tetachuck Lake during winter, and others are found south of Tetachuck Lake during sijrrmer, the majority of the caribou in the Tweedsmuir-Entiako area move from surrmer ranges in northern Tweedsmuir Park to winter ranges south of Tetachuck Lake. In suTTriary, Tweedsmuir-Entiako caribou were found predominantly in low elevation pine forests in the Entiako Lake area during winter, then moved north across Tetachuck Lake to strrmer ranges in northern Tweedsmuir Park. During spring migration, caribou used low elevation routes along the Chelaslie River drainage and along the north shore of Eutsuk Lake. Calving occurred throughout northern Tweedsmuir Park in a variety of habitats and by October, up to 50% of the caribou joined rutting aggregations in the Quanchus Mountains before moving south across Tetachuck Lake in November. Itcha-Ilgachuz Itcha-Ilgachuz caribou primarily used alpine and subalpine habitat in the Itcha and Ilgachuz Mountains for calving and surmer range. In 30 winter, most of these caribou were found in low elevation forested areas in the Chllcotin River, Punkutlaenkut Creek and Baezaeko River drainages; however, 100-300 caribou spent the winter on the north side of the Ilgachuz Mountains each year, primarily in the alpine. In April, about 80% of the radiocollared caribou locations were in low elevation pine forest habitat in the Chi 1 cotin River, Punkutlaenkut Creek and Cogllstiko River drainages (Figs.2,8,9). The other caribou locations were on the north side of the Ilgachuz Mountains in alpine and subalpine habitat. Movements back to surrmer range in the Itcha and Ilgachuz Mountains began in late April. By mid-May, caribou used forested habitats and meadows at the base of the Itcha and Ilgachuz Mountains and in the area between the two mountain ranges (Figs.10,11). During calving 1n June, and up to mid-July, radiocollared caribou cows used primarily high elevation alpine or subalpine habitat in the Itcha and Ilgachuz Mountains (Fig.2,8,10). Alpine and subalpine were also the most heavily used habitats in August and September. Movements by radiocollared caribou between the Itcha and Ilgachuz Mountains occurred occasionally throughout the surrmer. Caribou located at lower elevations in the surrmer and early f a l l used pine forests or meadows in the vicinity of the Itcha and Ilgachuz Mountains. During the rut in October, almost 90% of all radiocollared caribou locations were in alpine habitat 1n the Itcha and Ilgachuz Mountains (Fig.8). By November, caribou began moving to large, dry, fescue-lichen meadows and pine forests east of the Itcha and Ilgachuz Mountains ITCHA-ILGACHUZ 100 E 3 Lake LZ3 Alpine • 3 Subalpine Meadow Pine/Spruce/ Meadow Spruce/Meadow ESS Pine/Meadow EED Pine/Spruce A p r i l -May A u g -Sept D e c -March Fig.8. Proportion of r a d i o c o l l a r e d caribou l o c a t i o n s i n each habitat type i n the Itcha-Ilgachuz area, 1985/86, 1986/87 and 1987/88 combined. (N) = number of lo c a t i o n s . 03 ig .9. Rad ioco l l a red female c a r i b o u locations in the I t c h a - l l g a c h u z - R a i n b o w a r e a f rom N o v e m b e r - A p r i l , 1 9 8 5 / 8 6 , 1 9 8 6 / 8 7 , a n d 1987/88 comb ined . u ro T W E E D S M U I R T W E E D S M U I R P R O V I N C I A L Fig.11. Spring migration routes of radiocol lared female caribou in the Itcha-l lgachuz-Rainbow area . CO 35 (Figs.8,12). During early winter (mid November - early January), caribou used large meadows at the headwaters of the Chllcotin and Baezaeko Rivers and pine forests throughout the Chllcotin River, Punkutlaenkut Creek, Baezaeko River and Coglistiko River drainages (Fig.9). In the winters of 1985/86 and 1986/87, caribou moved out of these large meadows by mid-December, but during the winter of 1987/88, they used this habitat type until mid-late January. From January to March, caribou were primarily found 1n lower elevation pine forests throughout the Chi 1 cotin River, Punkutlaenkut Creek, Baezaeko River and Coglistiko River areas. Each winter, 5-15% of the radiocollared Itcha-Ilgachuz caribou were found on the north side of the Ilgachuz Mountains (Fig.8,9), where wind action reduced the amount of snow accumulation. The proportion of radiocollared caribou using alpine (20%) was similar to the proportion of the total population using alpine (300/1500) (Cichowski in prep.), indicating that the radiocollared caribou were a good representation of the population. These animals remained in high elevation alpine or subalpine habitat until early-mid December, then moved to lower elevation forested or subalpine habitat north of the Ilgachuz Mountains until mid-late January. From late January to the end of March, these caribou were again found 1n high elevation alpine or subalpine habitat on the north slopes of the Ilgachuz Range. Radiocollared caribou that spent the winter in the Ilgachuz Mountains during some years were found in lower elevation pine forests to the east of the Itcha Mountains during other years. ig.12. Fall migration routes of radiocol lared female caribou in the Itcha-l lgachuz-Rainbow a rea . 37 Overall, Itcha-Ilgachuz caribou calved and spent the surrmer 1n alpine habitat in the Itcha and Ilgachuz Mountains. In October, rutting occurred both above and below treeline, and by November caribou started moving to large fescue-lichen meadows on early winter ranges east of the Itcha Mountains. During winter, most of the caribou used low elevation pine forests east of the Itcha Mountains; however, between 5 and 15% of the Itcha-Ilgachuz caribou used alpine and subalpine habitat in the northern Ilgachuz Mountains. Rainbow Rainbow Mountain caribou calved and spent at least part of the surrmer in alpine habitat in the Rainbow Mountains. During winter, radiocollared Rainbow Mountain caribou were found in either the northern Rainbow Mountains, or in the northern Ilgachuz Mountains mixed with the Itcha-Ilgachuz caribou in the alpine. Radiocollared Rainbow Mountain caribou cows almost exclusively used high elevation alpine habitats from April to November (Fig.2,13). In May, all radiocollared caribou were found on the north side of the Rainbow Range prior to dispersing throughout the range for calving in June and for the rest of the surrmer (Fig. 10). During the three year study, only once did a radiocollared caribou move out of the Rainbow Mountains during the surrmer. In late August 1987, one radiocollared caribou moved from the Rainbow Mountains to the Itcha Mountains before moving to the Ilgachuz Mountains in late September, where she remained throughout the winter. During the rut in October, caribou concentrated RAINBOW 1 0 0 n CO c o ~ o o _ o 13 o n D o "D CD O O O XI O c CD O i_ CD D_ •E3 Lake • Alpine E D Subalpine Meadow B S P ine /Spruce / Meadow ESS Pine/Meadow ESI Pine/Spruce B Pine D e c -March F ig .13 . Proport ion of rad ioco l la red caribou locat ions in each habi tat type in the Rainbow area, 1985/86, 1986/87, and 1987/88 combined. (N) = number of l oca t ions . 03 00 39 on the north side of the Rainbow Mountains but some were also found scattered throughout the range. By November, some of the radiocollared caribou moved to the north side of the Ilgachuz Mountains (F1g.12). The proportion of radiocollared caribou that moved varied between 1/7 and 3/4 for the three years of the study. Radiocollared Rainbow caribou that were found in the northern Rainbow Mountains during winter, were found mostly in alpine habitat. Radiocollared Rainbow caribou that were found in the northern Ilgachuz Mountains during winter, followed the same habitat use patterns as the Itcha-Ilgachuz caribou that spent the winter in the northern Ilgachuz Mountains. During winter 1987/88, one radiocollared Rainbow caribou used low elevation forested habitat east of the Itcha Mountains. In surrnary, Rainbow Mountain caribou calved and spent the surmer primarily 1n alpine habitat throughout the Rainbow Mountains. During winter, Rainbow Mountain caribou predominantly used alpine and subalpine habitat in the northern Rainbow or northern Ilgachuz Mountains. WINTER FOREST COVER TYPE USE Tweedsmui r-Entiako During winter, caribou using forested habitat were found primarily in mature pine stands on low and poor quality growing sites (Fig.14,Table 3). Use of inrmature pine stands decreased over winter whereas use of mature pine stands on medium quality sites increased 40 0 . 6 - i 0 . 5 -0.4-0 . 3 -% 0 . 2 -_D '% 0.1-D o o.o CD Q-^ 0.8-0.4 0.2-0 . 0 -Tweedsmulr-Entiako K2L 3 M ft — £ L+P a f Z L Immature Mature Immature Mature Wetland/ Pine Pine Pine/ Pine/ Forested Spruce Spruce Wetland Lake Other tZD available EZ2 use Site Classes M = medium P = poor L = low T M Itcha-Ilgachuz M Li. Immature Pine Mature Pine Mature Pine/ Spruce Meadow/ Wetland Other F ig .14 . Proport ion of each forest cover type ava i l ab l e , and proport ion of rad ioco l la red car ibou locat ions in each forest cover type dur ing winter (December - March) i n the Tweedsmuir-Entiako (N=366), and I tcha-I lgachuz (N=369) winter ranges, December 1986 - March 1988 41 Table 3. Percent of forest cover types ava i l ab le and percent of rad ioco l la red car ibou locat ions 1n each forest cover type i n the Tweedsmuir-Entiako study area dur ing winter (December -March), ear l y winter (December - mid-January), mid winter (mid-January - mid-March), and l a te w in ter /ear ly spr ing (mid-March - A p r i l ) for 1986/87 and 1987/88 combined. S ign i f i cance at a=.05 (winter) or a=.10 (ear ly , mid and la te w in ter ) . Forest Use Use Use Cover Use Ear ly Mid Late Type Ava i lab le Winter Wi nter Winter Winter % % % % % PINE Immature 26.0 19.1 - 25.3 19.6 12.4 -Mature L+P 23.8 37.7 + 40.7 + 39.1 + 23.6 M 14.1 17.2 11.0 17.8 28.1 + PINE/SPRUCE Inrriature 5.2 2.7 - 4.4 2.2 - 2.3 Mature L+P 4.8 5.5 3.3 4.9 7.9 M 10.7 9.6 7.7 7.1 20.2 WETLAND/ FORESTED-WETLAND 2.6 1.9 - 3.3 1.8 3.4 LAKE 9.7 4.9 - 2.2 - 6.2 2.3 -OTHER 3.2 2.5 2.2 1 .3 0.0 -N 366 91 225 89 N = number of rad ioco l la red car ibou locat ions AGE CLASS Irrmature (0-80 years) Mature (>80 years) SITE CLASS L = Low P = Poor M = Medium OTHER Nonproductive(NP) p ine, NP p ine/spruce, NP spruce, NP brush, Rock, Mature spruce use > a v a i 1 a b i 1 1 t y use < a v a i l a b i l i t y 42 (Fig.15,Table 3). During late winter, mature pine/spruce stands on medium sites were also heavily used. Use of forest cover types by radiocollared caribou was different from availability during winter (X2=54.5, p<.05), early winter (X2=20.5, p<.05), mid winter (X2=41.2, p<.05) and late winter (X2=35.9, p<.05) (Table 3). Mature pine stands on low and poor quality sites were used more than were available during winter, early winter and mid winter. In late winter, pine/spruce stands on medium quality growing sites were heavily used, and mature pine stands on medium sites were used more than were available. Irrmature stands, wetlands and forested wetlands were used less than were available during winter. Lakes were also used less than were available during winter, early winter, and late winter. Itcha-Ilgachuz Caribou that wintered in forested habitat, almost exclusively used mature pine forests on low and poor quality growing sites and seldom used pine and pine/spruce stands on medium sites (Figs.14,16). Meadow/wetlands decreased in importance from being heavily used during early winter to not being used 1n late winter. Use of forest cover types was different from availability during winter (X2=231.5, p<.05), early winter (X2=57.1, p<.05), midwinter (X2=185.3, p<.05) and late winter (X2=58.9, p<.05). Mature pine stands on low quality sites were used more than were available and irrmature pine stands were used less than were available throughout the winter 43 0.6-i 0.5-0.4-0.3-0.2 0.1-0.0-! TWEEDSMUIR-ENT1AK0 M L + P early winter Y2L M L + P r !E2_ JZJL Immature Mature Immature Mature Wetland/ Pine Pine Pine/ Pine/ Forested Spruce Spruce Wetland Lake Other 0.6-0.5-0.4-| 0.3-0.2 O.H 0.0-1 74 M L + P / .4 mid winter M L+P IfcZL Immature Mature Immature Mature Wetland/ Pine Pine Pine/ Pine/ Forested Spruce Spruce Wetland Lake Other • available EZ3 use Site Classes M = medium P = poor L = low O.6-1 0.5-0.4H 0.3-0.2-1 0.1-0.0-M V, L + i late winter I Z L rzi i—n Immature Mature Immature Mature Wetland/ Pine Pine Pine/ Pine/ Forested Spruce Spruce Wetland Lake Other F i g . 15. Proport ion of each forest cover type a v a i l a b l e , and proport ion of rad ioco l la red car ibou locat ions in each forest cover type in the Tweedsmuir-Entiako winter range during ear ly winter (N=91), mid winter (N=225), and l a te winter (N=89), December 1986 -A p r i l 1988. 44 0.8-ITCHA-ILGACHUZ CL > o o w 0.6-0.4-0.2-M o.o-| 0.8-o xs § 0.6H w 0.4-0.2-0.0 22 M T / 2 early winter + P. I#>1 Immature Mature Pine Pine Mature Meadow/ Other Pine/ Wetland Spruce mid winter Immature Mature Mature Meadow/ Pine Pine Pine/ Wetland Spruce Other L~Z] available E23 use Site Classes M = medium P = poor L = low 0.8-. 0.6-0.4-0.2 0.0- I late winter M L+H Immature Pine Mature Mature Pine Pine/ Spruce Meadow/ Other Wetland F ig .16 . Proport ion of each forest cover type a v a i l a b l e , and proport ion of rad ioco l la red car ibou locat ions in each forest cover type in the I tcha-I lgachuz winter range during ear ly winter (N=113), mid winter (N=213), and l a te winter (N=63), December 1986 - A p r i l 1988. 45 (Table 4). During early winter, mature pine stands on medium quality growing sites were used less than were available, and during winter, mid-winter and late winter, mature pine/spruce stands on mediun sites were used less than were available. Mature pine/spruce stands on low and poor quality growing sites also were used less than were available during late winter. Meadow/wetlands were used more than were available during early winter and less than were available during mid and late winter (Table 4). WINTER CARIBOU HABITAT TYPE USE Tweedsmui r-Ent i ako During winter, radiocollared caribou used a variety of caribou habitat types (Figs.17,18). Between December and March, caribou used dry sites, primarily mature stands of Dry Lichen/Lichen Moss and Lichen Moss, and to a lesser extent, Moss - Dry Lichen/Lichen Moss and Moss/Seepage Forest - Aspen Forest. In early and mid winter (December -mid-March), both immature and mature stands of Dry Lichen/Lichen Moss, Lichen Moss, Dry Lichen/Lichen Moss Ecomosaic and Moss - Dry Lichen/Lichen Moss were extensively used. By late winter/early spring (mid-March - April) radiocollared caribou used predominantly moister sites consisting of Moss/Seepage Forest - Aspen Forest, Moss - Dry Lichen/Lichen Moss and Lichen Moss. Caribou use of caribou habitat types was different from availability for winter (X2=261.1, p<.05>, early winter (X2=101.8, 46 Table 4. Percent of forest cover types available and percent of radiocollared caribou locations in each forest cover type in the Itcha-Ilgachuz study area during winter (December -March), early winter (December - mid-January), mid winter (mid-January - mid-March), and late winter/early spring (mid-March - April) for 1986/87 and 1987/88 combined. Significance at a=.05 (winter) or a=.10 (early, mid and late winter). Forest Cover Type Available Use Winter Use Early Winter Use Mid Winter Use Late Winter PINE Irrmature L P Mature L P M % 15.7 17.9 17.8 23.1 4.6 3.8 -8.1 -45.8 + 24.1 3.5 5.3 -8.0 -33.6 + 23.9 0.9 -2.8 -8.0 -50.7 + 24.9 4.2 3.2 -14.3 50.8 + 23.8 6.3 PINE/SPRUCE Mature L+P M 3.5 4.1 3.8 1.1 3.6 2.7 4.7 0.5 0.0 0.0 MEADOW/ OPEN RANGE/ WETLAND OTHER 9.2 4.1 8.4 1.4 21.2 + 0.9 3.3 0.9 0.0 1 .6 N 369 113 213 63 N = number of radiocollared caribou locations AGE CLASS Irrmature (0-80 years) Mature (>80 years) SITE CLASS L = Low P = Poor M = Medium OTHER Nonproductlve(NP) pine, NP pine/spruce, NP spruce, NP brush, Rock, Irrmature pine (medium sites), Irrmature pine/spruce, Mature spruce use > a v a i l a b i l i t y use < aval 1abi11ty 47 0.4-Tweedsmuir-Entiako _o '5 > D TD C D a> <D Q . X l D 0.3-0.2-0.1-0.0-0.6-, 0.5-=3 O JD •C 0.4 D O 0.3-1 0.2-0.1-0.0-A M 7, \ M l+M l+M DLLM LM DLLM- MDLLM MSF/AF W/FW LAKE MOSAIC Itcha-Ilgachuz EL LL DLLM LM DLLM- MDLLM MSF MOSAIC W/FW FL SBPS- SBPS-DLK 0 T H CZD available EZ2 use Age Classes M = mature (>80 years) I = immature (0-80 years) 0 = nonforested F1g.17. Proport ion of each car ibou habitat type ava i l ab l e , and proport ion of rad ioco l la red car ibou locat ions in each car ibou habi tat type during winter (December - March), i n the Tweedsmuir-Entiako (N=355), and I tcha-I lgachuz (N=321) winter ranges, December 1986 - A p r i l 1988. 48 0.4-TWEEDSMUIR-ENT1AK0 0.3-0.2-0.1-S o.o-X I D 0.4 D > O T J C D 3 0) £ 0.2H '3 OA-D J C O 0.0 o o 0.4-, 0.3-0.2-0.1-0.0-early winter M X, M ^ s M Xy M 1 M r^i _LtM ^ I o , ny DLLM LM DLLM- MDLLM MSF/AF W/FW LAKE MOSAIC I ^ M mid winter M M M 1 l+M l+M DLLM LM DLLM- MDLLM MSF/AF W/FW LAKE MOSAIC late winter m M 7t M M M M £4 l+M DLLM LM DLLM- MDLLM MSF/AF W/FW MOSAIC LAKE CZI available EZ2 use Age Classes M = mature (>80 years) I = immature (0-80 years) 0 = nonforested Fig.18. Proportion of each caribou habitat type available, and proportion of radiocollared caribou locations in each caribou habitat type in the Tweedsmuir-Entiako winter during early winter (N=97), mid winter (N=221), and late winter (N=85), December 1986 - April 1988. 49 p<.05), mid winter (X2=251.2, p<.05) and late winter/early spring (X2= 38.9, p<.05). Mature Dry Lichen/Lichen Moss sites were used more than were available during winter, early winter and mid winter; and mature Lichen Moss sites were used more than were available during winter and mid winter (Table 5). Mature Lichen Moss sites also were heavily used in early winter and late winter. Use of irrmature Dry Lichen/Lichen Moss sites exceeded availability during mid winter. In winter and mid winter, mature and irrmature Moss/Seepage Forest - Aspen Forest types were used less than were available. Mature Moss/Seepage Forest - Aspen Forest was also used less than was available during early winter, but was heavily used during late winter. Forested wetland habitat was used less than was available during winter, mid winter and late winter and open wetland habitat was used less than was available during late winter. Other habitat types used less than their availability included mature Moss - Dry Lichen/Lichen Moss in winter and mid winter, and irrmature Dry Lichen/Lichen Moss Ecomosaic in late winter. Overall, mature Dry Lichen/Lichen Moss and Lichen Moss caribou habitat types were selected throughout the winter. In early winter, caribou used a variety of habitats equally, and by late winter, Moss/Seepage Forest - Aspen Forest had Increased in importance. Itcha-Ilgachuz Use of caribou habitat types in irrmature stands was less than availability (X2=75.3, p<.05) (Table 6). Use/availabi1ity analysis was therefore performed only on mature and open habitat types. 50 Table 5. Percent of caribou habitat types available and percent of radiocollared caribou locations in each caribou habitat type 1n the Tweedsmulr-Entiako study area during winter (December -March), early winter (December - mid-January), mid winter (mid-January - mid-March), and late winter/early spring (mid-March - April) for 1986/87 and 1987/88 combined. Significance at ot=.05 (winter) or a=.10 (early, mid and late winter). Caribou Use Use Use Habi tat Use Early Mid Late Type Aval 1 able Winter Winter Winter Winter Jte % % 3 % DLLM (I) 4.0 3.3 10.3 10.0 + 5.9 (M) 3.1 12.3 + 12.4 + 14.9 + 4.7 LM (I) 6.9 4.7 3.1 5.0 2.4 (M) 12.6 28.4 + 20.6 33.9 + 23.5 DLLM-MOSAIC (I) 2.5 5.3 9.3 4.1 0.0 -(M) 4.2 4.7 11.3 3.6 7.1 MDLLM (I) 4.6 2.8 2.1 4.1 3.5 (M) 20.4 12.8 - 15.5 9.0 - 12.9 MSF/AF (I) 4.2 1.1 - 2.1 0.5 - 1 .2 (M) 22.3 11.1 - 5.2 - 5.9 - 35.3 W/FW (0) 3.0 1.7 2.1 1.8 0.0 -(I+M) 3.5 1.4 - 4.2 0.9 - 0.0 -Lake 8.8 5.3 - 2.1 - 6.3 3.5 N 355 97 221 85 N = number of radiocollared caribou locations I = Immature (0-80 years) M = Mature (>80 years) 0 = No age class + use > a v a i l a b i l i t y use < a v a i l a b i l i t y Table 6. Percent of caribou habitat type age classes available and percent of radiocollared caribou locations in caribou habitat type age classes 1n the Itcha-Ilgachuz study area during winter, for 1986/87 and 1987/88. Significance at a=.05. Age Class Avai Table Use - Winter % % 0 (no age class) 4.3 4.1 1-3 (0-80 years) 26.6 6.1 -4-5 (>80 years) 69.1 89.8 + + use > a v a i l a b i l i t y use < a v a i l a b i l i t y 52 Radiocollared caribou used primarily Dry Lichen/Lichen Moss and Lichen Moss habitat types in the MSd blogeoclimatic zone during winter (Fig.17). In early winter Fescue Lichen sites were heavily used and in late winter/early spring, Dry L1chen/K1nn1k1nn1ck sites in the SBPSxc subzone were heavily used (Fig.19, Table 7). Caribou use of caribou habitat types was different from availability for winter (X2=214.6, p<.05), early winter (X2=158.4, p<.05), mid winter (X2=251.8, p<.05) and late winter/early spring (X2=58.0, p<.05). Dry Lichen/Lichen Moss was heavily used during early winter, and use of Dry Lichen/Lichen Moss exceeded availability during winter, mid winter and late winter (Table 7). Moss/Seepage Forest types were used less than were available throughout winter. Fescue Lichen types were used more than were available during winter and early winter, and less than were available during late winter/early spring. Conversely, SBPSxc biogeoclimatic zone types were used less than were available in winter and early winter, but in late winter/early spring, Dry Lichen/Kinnikinnick in the SBPSxc subzone was used more than was available. Wetlands and forested wetlands in mid and late winter, and Dry Lichen/Lichen Moss Ecomosaics in late winter were used less than were available. Overall, mature Dry Lichen/Lichen Moss and Lichen Moss were the most heavily used caribou habitat units during winter. In early winter Fescue Lichen meadows were important, and 1n late winter Dry Lichen/Kinnikinnick sites in the SBPSxc subzone were heavily used. 53 0.6-, 0.5 0.4 0.3H 0.2 0.1 0.0 JD _o > D ~0 C D a> V) ZJ <D CL 0.3 0.6 0.5H 0.4 JD D JZ =3 o JD * i _ D O 0.2 o.H 0.0 0.6 0.5H 0.4 0.3-0.2-0.1-0.0 ITCHA-ILGACHUZ early winter 1 UL l DLLM l r LM DLLM— MDLLM MSF W/FW FL S B P S - S B P S MOSAIC DLK OTH mid winter 1 LZL DLLM LM D L L M - MDLLM MSF W/FW FL SB PS - S B P S -M0SAIC DLK OTH J2 late winter i—"i EL DLLM LM D L L M - MDLLM MSF W/FW FL S B P S - S B P S -MOSAIC DLK OTH • available fZ2 use F ig .19 . Proport ion of each car ibou habi tat type ava i l ab l e , and proport ion of rad ioco l la red car ibou locat ions 1n each car ibou habi tat type in the I tcha-I lgachuz winter range during ear l y winter (N=100), mid winter (N=178), and la te winter (N=62), December 1986 - A p r i l 1988. Table 7. Percent of caribou habitat types available and percent of radiocollared caribou locations in each caribou habitat type in the Itcha-Ilgachuz study area during winter (December -March), early winter (December - mid-January), mid winter (mid-January - mid-March), and late winter/early spring (mid-March - April) for 1986/87 and 1987/88 combined. Significance at a=.05 (winter) or a=.10 (early, mid and late winter). Caribou Use Use Use Habitat Use Early Mid Late . Type Available Winter Winter Winter Winter _% % _% _% % DLLM 27.0 55.5 + 40.0 57.3 + 51.6 + LM 16.7 17.8 19.0 19.7 9.7 DLLM-MOSAIC 3.9 2.5 5.0 2.2 0.0 -MDLLM 4.5 2.2 2.0 1.7 5.7 MSF 18.3 5.6 - 8.0 - 5.6 - 1.6 -W/FW 8.4 2.8 - 6.0 2.2 - 0.0 -FL 2.6 7.8 + 18.0 + 4.5 0.0 -SBPS-DLK 10.4 5.0 - 1.0 - 3.9 - 29.0 + SBPS-OTHER 8.2 0.9 - 1.0 - 2.8 - 4.8 N 321 100 178 62 N = number of radiocollared caribou locations + use > a v a i l a b i l i t y use < a v a i l a b i l i t y 55 WINTER SNCW ACCUMULATION AND SINKING DEPTH Snow accumulation 1n all 3 habitat types (open wetland, irrmature pine, and mature pine) increased between December and February then remained relatively constant through February and March in both 1986/87 and 1987/88 (Fig.20). Snow depths 1n the mature and irrmature pine stands were approximately equal and between 10 and 15 centimeters less than in the open wetland. Less snow accumulated in the Moore Creek area in the winter of 1987/88 than in the winter of 1986/87. On average, snow accumulation at the snow stations 1n the wetland in 1987/88 was about 30 centimeters less than in 1986/87 for the same time period. Maximum mean snow depth 1n 1987/88 (March 1988) was lower than minimum mean snow depth in 1986/87 (December 1986). Caribou sinking depth increased linearly with observer sinking depth (Fig.21). The relation was used to predict caribou sinking depth in each habitat type by using observer sinking depth measurements at the snow stations. Predicted caribou sinking depth 1n open habitat exceeded predicted caribou sinking depth in both irrmature pine and mature pine forests during both years (Fig.22). Trends in predicted caribou sinking depth reflected trends in snow depth 1n that predicted caribou sinking depth averaged 15-30 centimeters greater in 1986/87 than in 1987/88. In 1987/88 predicted caribou sinking depth in open habitat did not exceed 45 cm. In summary, snow depth and predicted sinking depth were greater in open rather than forested habitat. Fig.20. Mean snow depth at snow stations in 3 habitat types (wetland, mature and immature pine stands) at Moore Creek, in the Itcha-Ilgachuz winter range, December 1986 - March 1987, December 1987 - March 1988. F ig .21 . Caribou s ink ing depth versus observer s ink ing depth in the Tweedsmuir-Entiako and I tcha-I lgachuz winter ranges in 1985/86, 1986/87 and 1987/88 combined (F=39082, p<.05, r 2 . 9 0 ) . -vl .22. P r e d i c t e d c a r i b o u s i n k i n g depth at snow s t a t i o n s i n 3 h a b i t a t types (wetland, mature and immature pine stands) at Moore Creek, i n the I t c h a - I l g a c h u z winter range, December 1986 - March 1987, December 1987 - March 1988. 59 WINTER FEEDING ECOLOGY C r a t e r i n g versus a r b o r e a l l i c h e n f e e d i n g On the I t c h a - I l g a c h u z and Tweedsmuir-Entiako w i n t e r ranges, c r a t e r i n g was the primary f e e d i n g a c t i v i t y i n pi n e f o r e s t s (Table 8 ) . Pine/spruce stands on the I t c h a - I l g a c h u z and Tweedsmuir-Ent1ako c a r i b o u winter ranges were used predominantly f o r a r b o r e a l l i c h e n f e e d i n g ; however more c r a t e r i n g occurred i n pine/spruce stands on the Tweedsmuir-En t l a k o winter range than on the It c h a - I l g a c h u z winter range. Spruce stands i n Tweedsmuir-Entiako were used p r i m a r i l y f o r a r b o r e a l l i c h e n f e e d i n g . In a l l f o r e s t e d h a b i t a t types combined (weighted f o r the p r o p o r t i o n of telemetry l o c a t i o n s 1n each f o r e s t e d t y p e ) , c r a t e r s made up 78% of f e e d i n g s i t e types i n the Itcha-Ilgachuz-Rainbow w i n t e r range and 63% of f e e d i n g s i t e types i n the Tweedsmuir-Entiako winter range (Table 8 ) . Feeding s i t e s i n open h a b i t a t s such as wetlands, lakes and f e s c u e - l i c h e n meadows c o n s i s t e d mostly of c r a t e r i n g s i t e s . Only 2 i n c i d e n t s of browsing on shrubs were observed d u r i n g the 3 winter f i e l d seasons. I n p i n e , pine/spruce and spruce f o r e s t s combined, c a r i b o u 1n the Tweedsmuir-Entiako area used arboreal l i c h e n s t o a gr e a t e r extent than c a r i b o u 1n the I t c h a - I l g a c h u z area throughout the winter (Table 9 ) . Arboreal l i c h e n use was grea t e r d u r i n g March than d u r i n g January and February i n both Tweedsmuir-Entiako and I t c h a - I l g a c h u z areas. The December sample i n Tweedsmuir-Entiako was based on o n l y one set of t r a c k s i n pine/spruce h a b i t a t and was p o s s i b l y not r e p r e s e n t a t i v e of fe e d i n g s i t e types chosen d u r i n g December. Arboreal l i c h e n f e e d i n g was the predominant f e e d i n g a c t i v i t y i n f o r e s t e d wetlands. 60 Table 8. Percent of feeding s i t e types investigated ( c r a t e r i n g vs. arboreal l i c h e n feeding) i n the winter ranges of the Tweedsmuir-Entiako and Itcha-Ilgachuz caribou, from January-March 1986, December 1986-March 1987, December 1987- March 1988 combined. Tweedsmuir-Entiako caribou winter range % % arboreal # s i t e s Habi tat c r a t e r i n g feeding i n v e s t i g a t e d Pine 72 28 816 Spruce 15 85 52 P1ne/Spruce 32 68 228 Total Forest 63 37 1096 Forested Wetland 21 79 58 Wetland 0 100 3 Lake/Creek 100 0 52 Itcha-Ilgachuz caribou winter range % % arboreal # s i t e s Habi t a t c r a t e r i n g feeding i n v e s t i g a t e d Pine 79 21 1044 Pine/Spruce 10 90 20 Total Forest 78 22 1064 Forested Wetland 10 90 10 Wetland . 100 0 120 Fescue-Lichen 100 0 84 Lake/Creek 100 0 14 Alpine 100 0 26 61 Table 9. Percent of feeding site types Investigated (cratering vs. arboreal lichen feeding) in forested habitats in the winter ranges of the Tweedsmulr-Entiako and Itcha-Ilgachuz caribou, by month, for January-March 1986, December 1986-March 1987, December 1987- March 1988 combined. Tweedsmuir-Entiako caribou winter range December January February March % cratering 19 65 68 53 % arboreal feeding 81 35 32 47 # sites investigated 30 624 150 225 Itcha-Ilgachuz caribou winter range % % arboreal cratering feedi ng December 81 19 January 82 18 February 89 11 March 66 34 # sites Investigated 21 183 443 406 62 Crater selection Terrestrial lichen abundance: Terrestrial lichens were the most frequently occurring vegetation type found in craters in all forest types combined (Table 10). At least one of the terrestrial lichen genera (Cladonia spp., Cladina spp. and Stereocaulon spp.) was found 1n 99% of all craters in forests in the Itcha-Ilgachuz area and in 100% of all craters in forests in the Tweedsmuir-Entiako area. Of the terrestrial lichens present, Cladina spp. were most corrmon. Terrestrial lichens were not as prevalent 1n non-crater sites. Of non-crater sites in forested habitat, 33% contained terrestrial lichens 1n the Tweedsmuir-Entiako caribou winter range, and 70% contained terrestrial lichens in the Itcha-Ilgachuz caribou winter range. The proportion of craters containing terrestrial lichens was greater than the proportion of non-crater sites containing terrestrial lichens 1n both Tweedsmuir-Entiako (X2=483.9, p<.05) and Itcha-Ilgachuz (X2=196.8, p<.05) areas. Terrestrial lichens were found in moderate to high quantities in craters, whereas in non-crater sites, terrestrial lichens were absent or found in low to moderate quantities (Fig.23). The abundance of terrestrial lichens 1n craters was greater than the abundance of terrestrial lichens 1n non-crater sites (Tweedsmuir Entiako X2=384.4, p<.05; Itcha-Ilgachuz X2=279.2, p<.05). Overall, caribou selected areas with greater terrestrial lichen availability for cratering. 63 Table 10. Frequency of occurrence of vegetation 1n craters (C) and 1n non-crater sites (NCS) 1n the winter ranges of the Tweedsmuir-Ent1ako and Itcha-Ilgachuz caribou, from January-March 1986, December 1986-March 1987, December 1987-March 1988 combined. Tweedsmuir-Ent1ako No. C / NCS Vegetation present Arctostaphylos uva-ursl Betula glandulosa Car ex spp. Corpus canadensis Brpetrum nigrum Equlsetum spp. Forbes Grasses Ice/Slush Junlperus spp. Llnnaea boreal is Lycopodium spp. Mosses Pinus con torta Rosa spp. Sal1x spp. Shepherdia canadensis T e r r e s t r i a l l i chens Cladonia spp. Cladina spp. Stereocaulon spp. Cladonia/Cladina/Ster Pel tigera spp. Vaccinium spp. PINE PINE/ SPRUCE TOTAL FOREST Frozen ground c NCS C NCS C NCS 827 187 2 5 829 192 .15 . 17 .50 . 16 . 16 .01 .20 . 02 .01 1.00 .002 . 01 .01 .50 .20 .001 .02 .18 .26 .40 .18 .26 .004 .004 .006 .006 .33 .25 .50 .20 .34 .20 .04 .09 .20 .04 . 09 .02 . 005 .02 . 005 .005 .005 .21 .33 .60 .21 .39 .01 .01 .01 .01 .001 . 005 .001 . 005 .03 .03 .63 .50 .60 .63 .51 .77 .31 .20 .76 .31 .11 . 09 .08 .09 .99 . 70 .80 .99 . 70 .06 . 17 .06 . 17 .08 . 10 .20 .08 . 10 .005 . 005 WETLAND/ FOR .WET. C NCS 120 20 FESCUE-LICHEN .09 .24 .08 .85 .03 .02 .02 .35 . 70 .30 . 10 . 15 C 84 .04 .02 .04 .99 .15 .98 .35 1.00 NCS 0 LAKE/ CREEK C ACS 14 3 ALPINE C NCS 26 0 .38 .15 1.00 1.00 .88 .77 1.00 Itcha-Ilgachuz PINE SPRUCE PINE/ SPRUCE TOTAL FOREST WETLAND/ FOR.WET. LAKE/ CREEK C NCS C NCS C NCS C NCS C ACS No. C / NCS 589 127 8 23 73 63 670 213 12 22 Veqetation present Arctostaphylos uva-urs1 .40 .42 .25 . 13 .45 .22 .41 .33 Betula glandulosa .01 . 005 . 09 Carex spp. .04 .01 .001 .005 .55 Cornus canadensis . 01 . 04 .03 .003 .01 Brpetrum nigrum .005 .03 .04 .03 .02 .007 . 17 Equisetun spp. Forbes .005 .06 .25 . 09 .03 .01 .04 Grasses .04 . 06 .13 .22 .10 . 06 .05 . 08 1.00 . 78 Ice/Slush .23 Junlperus spp. .01 .01 . 05 .001 .02 Ledum groenlandlcum .002 .07 .02 .01 . 005 . 14 Linnaea borea11s .002 .01 .04 . 03 .001 .02 Lycopodium spp. .04 .02 Mosses .25 .50 .63 . 78 .30 . 73 .26 .60 .50 .50 Pinus contort a .01 .01 .02 .01 . 005 Rosa spp. .04 . 005 Sallx spp. .01 .005 .36 Shepherdia canadensis .04 .13 .09 .01 .04 .01 T e r r e s t r i a l l i chens Cladonia spp. .55 . 19 .36 . 08 .52 . 12 Cladina spp. .83 . 16 .97 .23 .91 . 17 Stereocaulon spp. .03 .02 .02 . 005 Cladonia/Cladina/Ster .99 .37 .75 . 17 .95 .30 1 .00 .33 Pel tiger a spp. .04 .20 .13 .09 .19 . 10 .06 . 15 Vaccinium spp. .003 .003 Frozen ground .05 .01 . 13 .001 . 07 C 52 NCS 20 .08 .92 1.00 TWEEDSMUIR-ENTIAKO 64 ITCHA-ILGACHUZ Fig.23. Proportion of craters (C) and non-crater sites (NCS) containing % ground cover classes (0%, 1%, 2-14%, 15-39%, 40-100%) of terrestrial lichens (Cladina spp. Cladonia spp., Stereocaulon spp. combined) 1n all forested habitat types combined in the Tweedsmuir-Entiako (C=351, NCS=213), and Itcha-Ilgachuz (C=570, NCS=185) winter ranges (December - March, 1986/87, 1987/88). 65 On the Itcha-Ilgachuz caribou winter range, fescue-lichen meadows were heavily used during early winter. The most frequently occurring vegetation types in craters in those meadows were terrestrial lichens (contained in 100% of the craters) and grasses (contained in 99% of the craters) (Table 10). As winter progressed, use of wetlands and forested wetlands increased and use of fescue-lichen meadows decreased. Ice and/or free water were present 1n 85% of craters in wetlands on the Itcha-Ilgachuz winter range. The proportion of craters containing sedges was lower than the proportion of non-crater sites containing sedges (X2=40.0, p<.05), and the proportion of craters containing ice was greater than the proportion of non-crater sites containing ice (X2=39.3, p<.05), suggesting that caribou were probably not cratering for food but for ice or free water 1n wetlands. Caribou also cratered on or along lakes and creeks in both Itcha-Ilgachuz and Tweedsmuir-Entiako winter areas (Table 10). These craters almost exclusively contained ice or free water only. In surrmary, Caribou use of open areas included use of fescue-lichen for terrestrial lichen feeding during early winter, and use of wetlands for obtaining water throughout the year. Canopy cover: The distribution of canopy cover classes at craters was different from the distribution of canopy cover classes at non-crater sites 1n Tweedsmuir-Entiako (X2=42.8, p<.05) and Itcha-Ilgachuz (X2=34.9, p<.05) winter ranges (F1g.24). Craters were found more often than non-crater sites in forested areas with very open (<5% canopy cover) and open (6 6 6 TWEEDSMUIR-ENTIAKO ITCHA- ILGACHUZ CO 0-6-1 to % CANOPY COVER g.24. Proportion of craters (C) and non-crater s i t e s (NCS) i n % canopy cover classes (<5%, 6-10%, 11-15%, >20% canopy cover) i n a l l forested habitats combined 1n the Tweedsmuir-Entiako (C=293, NCS=65) and Itcha-Ilgachuz (C=446, NCS=105) winter ranges (December 1986 - March 1987, December 1987 - March 1988). 67 10%) canopies. Conversely, non-crater sites were found more often than craters in forested areas with more closed canopies (11-15%, 16-20%, >20% canopy cover). An interaction between canopy closure and percent ground cover of terrestrial lichens was apparent in crater site selection (Table 11). Crater sites were found primarily in stands with both open canopies and abundant terrestrial lichens, whereas areas where caribou had not cratered occurred 1n less open stands with lower quantities of terrestrial lichens. These results indicate that lichen abundance 1s the most important factor affecting feeding site selection. Areas with abundant lichen are often poor growing sites with open canopies. Snow conditions: Both snow depth and snow penetrability at craters and non-crater sites varied over the winter (F1gs.25,26,27). On the Itcha-Ilgachuz winter range, snow depth was greater at craters than at non-crater sites during the early February sampling session in 1987 (t=3.5, p<.05) and during the early March sampling session 1n 1988 (t=3.5, p<.05). Snow penetrability at craters was greater than snow penetrability at non-crater sites during the early February (t=2.2, p<.05) and early March (t=2.8, p<.05) sampling sessions in 1988. On the Tweedsmuir-Entiako winter range snow depth was greater at crater sites than at non-crater sites during mid-January 1987 (t=7.4, p<.05) but not during February and March (Fig.25). In 1988, snow depths of craters and non-crater sites were similar in January, but snow depth 68 Table 11. Percentage of craters (C) and non-crater sites (NCS) found in different canopy closure / terrestrial lichen availability classes in all forested habitat types combined 1n the Tweedsmuir-Entiako and Itcha-Ilgachuz caribou winter ranges, December 1987 - March 1988. % ground cover of terrestrial lichens % canopy closure 0% 1% 2-14% 15-39% 40-100% Total Tweedsmuir-Entiako 1-5% C 0.3 0 5.8 23.5 23.5 156 NCS 17.2 1.6 3. 7 4.7 0 17 6-10% C 0 0 3.4 13.0 10.6 79 NCS 10.9 3. 1 0 1.6 0 10 11-15% C 0 0.3 3.4 7.5 6.5 52 NCS 40.6 1.6 7.3 r.6 0 33 16-20% C 0 0 0.3 0.3 1.4 6 NCS 6.3 0 0 0 0 4 Total C 1 1 38 130 123 293 NCS 48 4 7 5 0 64 cha-Ilgachuz 1 -5% C 0.2 0 3.4 10.3 14.6 127 NCS 3.8 2.9 a.6 6. 7 1.9 25 6-10% C 0.4 0 6.7 23.8 20.0 227 NCS 12.4 3.8 6.7 8.6 7.0 34 11-15% C 0.4 0 3.4 9.4 7.0 90 NCS 14.3 2.9 11.4 9.5 0 40 16-20% C 0 0.2 0 0.2 0 2 NCS 1.9 0 2.9 1.9 0 6 Total C 4 1 60 195 185 446 NCS 34 10 37 27 3 105 TWEEDSMUIR-ENTIAKO 1987 69 O C r a t e r s  9 N o n - c r a t e r s i t e s -Or = 4 -JAN FEB MAR APR .25. Mean snow depths of craters and non-crater sites 1n all forested habitats combined, during sampling sessions conducted on the Tweedsmuir-Ent1ako winter range, January - March 1987, January -March 1988. Error bars are 95% confidence limits. TWEEDSMUIR-ENTIAKO 1988 70 1.1-1 1.0-0 .9 ->- 0 .8 -Zz J5 0.7-D — 0 .6 -c pe 0.5 -MO 0.4-c CO 0 . 3 -0 .2-0.1-0 .0 -O Craters • N o n - c r a t e r sites JAN FEB MAR APR ITCHA- ILGACHUZ 1988 1.1-1 1.0-0 .9 -0 . 8 -s 0.7-p "5 0 .6 -c a> Q. 0.5 -MO 0.4-c to 0 .3 -0 .2-0.1-0 .0 -CP— O Craters • N o n - c r a t e r sites JAN FEB MAR APR Fig.26. Mean snow p e n e t r a b i l i t y (weight s i n k i n g depth + snow depth) of c r a t e r s and non-crater s i t e s i n a l l forested habitat types combined, during sampling sessions conducted on the Tweedsmuir-Entiako and Itcha-Ilgachuz winter ranges, December 1987 - March 1988. Error bars are 95% condfidence l i m i t s . ITCHA-ILGACHUZ 1986/87 71 Fig.27. Mean snow depths of craters and non-crater sites in all forested habitat types combined, during sampling sessions conducted on the Itcha-Ilgachuz winter range, December 1986 - March 1987, December 1987 - March 1988. Error bars are 95% confidence limits. 72 at craters exceeded snow depth at non-crater sites during the late February (t=6.0, p<-05), early March (t=6.3, p<.05) and late March (t=2.1, p<.05) sampling sessions. Snow penetrability decreased in both non-crater sites and craters throughout the winter in Tweedsmuir-Entiako (Fig.26). Snow penetrability at cratering sites was greater than snow penetrability at non-crater sites during both early March (t=5.7, p<.05) and late March (t=3.1, p<.05) sampling sessions in 1988. Overall, snow depth was regularly greater at craters than at non-cratering sites and snow penetrability tended to be greater at craters than at non-crater sites later in the winter. A surrmary of data from winter feeding site figures is presented in Appendix II. FECAL FRAGMENT ANALYSES AND FECAL NITROGEN Terrestrial lichens and arboreal lichens were the predominant food types in fecal samples during winter months (F1g.28). During surrmer, grasses, sedges, forbs, and lichens were heavily used. In early spring, forbs comprised 20% of the vegetation found in fecal samples. In the surrmer, lichen use decreased and grasses, sedges and forbs made up more than 50% of vegetation in fecal pellet groups. Conifers, shrubs and mosses were present in low quantities throughout the year. By October, terrestrial and arboreal lichens made up over 80% of vegetation in fecal pellets. Terrestrial and arboreal lichens were the most heavily used food items during the f a l l . APR MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB MAR APR Fig.28. Percent of vegetation types found in fecal samples collected in the Itcha-Ilgachuz area in 1985/86. Samples from April, May and December were collected in 1987. 74 Percent fecal nitrogen values were relatively constant at about 1.5% during f a l l , winter and spring and Increased in the surrmer to about 2.5% (Fig.29). Low fecal nitrogen during calving in early June indicates female migrated before new vegetation was available on the calving grounds. There was l i t t l e monthly or year to year variation 1n either the proportion of each Vegetation type or the percent fecal nitrogen of winter fecal samples in both Tweedsmuir-Entiako and Itcha-Ilgachuz winter ranges (Figs.30,31). In general, terrestrial and arboreal lichens were the most abundant vegetation types in fecal samples collected during winter months. Terrestrial lichen was more abundant than arboreal lichen and combined they made up 50-75% of vegetation types found in fecal samples. Terrestrial lichens were more frequent in fecal groups collected in the Itcha-Ilgachuz area than in the Tweedsmuir-Entiako area. Conifers and mosses were the next most abundant vegetation types. The percentage of grasses, sedges and forbs in fecal samples collected in the Tweedsmuir-Entiako area increased from 7% in early winter to 27% in late winter 1n 1986/87. In general, terrestrial lichens were the most important winter forage, although arboreal lichens were also important, especially 1n the Tweedsmuir-Entiako area. A surmary of all fecal sample data is presented in Appendix 3. Fig.29. Percent fecal nitrogen levels in fecal samples collected in the Itcha-Ilgachuz in 1985/86. Samples from April, May and December were collected in 1987. Error bars are 95% confidence limits. Tweedsmuir-Entiako 1986 Tweedsmuir-Entiako 1986/87 Fig.30. Percent fecal nitrogen levels and percent of vegetation types found in fecal samples collected in the Tweedsmuir-Entiako winter range in 1985/86 and 1986/87. Error bars are 95% confidence limits. (Vegetation type key on Fig.28). Itcha-Ilgachuz 1986 Itcha-Ilgachuz 1986/87 .31. Percent fecal nitrogen levels and percent of vegetation types found 1n fecal samples collected in the Itcha-Ilgachuz winter range in 1985/86 and 1986/87. Error bars are 95% confidence limits. (Vegetation type key on Fig.28). 78 DISCUSSION SEASONAL MOVEMENTS AND HABITAT USE Tweedsmuir-Entiako caribou spent the winter south of Tetachuck Lake in low elevation forested habitat in the Entiako Lake area, spent the s u T r n e r in northern Tweedsmuir Park and the adjacent mountains to the west, and moved across Tetachuck Lake during fall and spring migration. Itcha-Ilgachuz caribou spent the s L r n n e r in the Itcha and Ilgachuz Mountains, and were found 1n low elevation forested habitat to the east of the Itcha Mountains or in the alpine on the north side of the Ilgachuz Mountains during winter. Rainbow Mountain caribou were found primarily in the Rainbow Mountains during siirrner and on both the north side of the Rainbow Mountains and the north side of the Ilgachuz Mountains during winter. Spring migration Caribou in the Tweedsmuir-Entiako and Itcha-Ilgachuz-Rainbow areas displayed generally consistent movement patterns between winter and surrmer ranges. Spring migration occurred along low elevation routes where snow was minimal or absent. In fact, some Tweedsmuir-Entiako caribou moved up to 40 kilometers off the most direct route to surrmer ranges, to follow low elevation areas along the Chelaslie River. Habitat use by caribou during spring migration was restricted primarily to those habitats occurring at low elevations. During late winter and spring migration, caribou appeared to be feeding on green vegetation in 79 snowfree areas. Relatively snowfree areas were also important during spring migration for barren-ground caribou in northern Yukon (Surrendi and DeBock 1976) and woodland caribou in west-central Alberta (Edmonds and Bloomfield 1984). In the Tweedsmuir-Entiako area, during spring migration, caribou moved north across Tetachuck Lake. Although crossing occurred along the length of the lake, the main crossing points appeared to be along the east half of the lake and at the Tetachuck River (between Tetachuck Lake and Natalkuz Lake). Movements of Rainbow caribou from the Ilgachuz to the Rainbow Mountains were inferred from caribou locations before and after migration since the frequency of flights was insufficient to detect actual routes used. It appeared that most movement occurred north of Lessard Lake. Although Rainbow caribou crossed the Dean River Road when moving between the Rainbow and Ilgachuz Mountains, the road currently supports l i t t l e traffic and does not appear to hinder caribou movements. Roads with low traffic volume do not appear to act as barriers to caribou and reindeer movement (Bergerud et al. 1984b, Gauthier et al. 1976, Russell and Martell 1976, Skogland 1986). Currently there are no roads transecting spring migration routes of the Itcha-Ilgachuz and Tweedsmuir-Entiako caribou. 80 Calving grounds By calving time in early June, adult female caribou had returned to surrmer ranges. In the Itcha-Ilgachuz-Rainbow area, almost 100% of adult female radiocollared caribou were found in alpine habitat in the Itcha, Ilgachuz and Rainbow Mountains. In the Itcha Mountains, caribou cows were found throughout the alpine during calving but were primarily found alone on ridgetops (Cichowski, in prep.). By the end of June, cows and calves in the Itcha-Ilgachuz-Rainbow Mountains formed post-calving aggregations and by late June/early July, were joined by bulls. Dispersion in mountains is considered to be an antipredator strategy of woodland caribou (Bergerud et al. 1984a, Seip 1989). Adult female caribou will forgo forage quality at lower elevations to calve high in mountains. This strategy spaces caribou away from alternate prey such as moose (Alces alces) which occupy lower elevation habitats at this time, and increases predator searching time for calves, making i t difficult for predators to subsist on a diet of caribou calves (Bergerud and Page 1987, Seip 1989). Adult female caribou moved to alpine habitat before emergence of new vegetative growth, as indicated by low fecal nitrogen values. In eastern Canada where alpine ridges are not available, caribou calve alone on islands in lakes or close to the shoreline on the mainland away from other alternate prey (Bergerud and Page 1987, Shoesmith and Storey 1977). Dispersion by caribou in the Itcha, Ilgachuz and Rainbow Mountains during calving was consistent with the antipredator strategy described by Bergerud et al. (1984b). 81 In northern Tweedsmuir Park, caribou were widely dispersed during calving, but only 30% were found above treeline (50% were at low elevations). Caribou cows in Spatsizi Provincial Park displayed similar behaviour as they were also found below treeline during calving (Hatler 1986). In northern Tweedsmuir Park, calf production of caribou cows found in the alpine was greater than calf production of caribou cows found below treeline (Cichowski 1989). This result implies that either caribou cows moved to lower elevations after losing a calf, or caribou calves born at lower elevations were more susceptible to mortality. Data collected in the Tweedsmuir-Entiako area were inadequate for distinguishing between the two possibilities; however, either way, high elevation calving areas appear to be important for calf survival during surrmer. Bergerud (1988) suggested that calving habitat may be the most critical habitat for woodland caribou populations and should be protected from habitat destruction and disturbance. Although no bull caribou were radiocollared for this study, ground observations during calving in the Itcha Mountains indicated that bulls were not abundant in alpine areas until late June (Cichowski 1n prep.). Woodland caribou bulls in Spatsizi Park (Hatler 1986) and west-central Alberta (Edmonds and Bloomfield 1984) were also absent from alpine areas until late June/early July. Barren-ground caribou bulls in the Porcupine caribou herd moved northward to surrmer ranges following plant phenology and snowmelt whereas female caribou returned to summer ranges much earlier (Marten et al. 1986). Bulls in the Itcha Mountains probably also followed plant phenology to surrmer range 1n the alpine, further indicating that females which occupy these areas earlier during 82 the calving season do so at the expense of better forage quality found at lower elevations. Bulls became abundant in alpine habitat by late June when fecal nitrogen values of cows had increased, Indicating that improved forage quality was available at that time. The presence of bulls below treeline during calving also suggests that cows were not forced into alpine areas by insect harassment; otherwise, bulls would also be found primarily in alpine habitat during calving. Strrmer range Caribou habitat use during surrner (mid-July - September), reflected abundant and nutritious forage available at the time and lack of barriers to movement (i.e. snow). Radiocollared caribou cows were found in a variety of habitat types between 500 and 2200 meters in northern Tweedsmuir Park, reflecting the diverse topography and vegetation. Itcha-Ilgachuz caribou similarly used a variety of habitat types whereas Rainbow caribou dispersed throughout the Rainbow Mountains in alpine habitat only. Fall / rutting habitat By October, use of alpine habitat increased in the Tweedsmuir-Entiako and Itcha-Ilgachuz-Rainbow areas. In northern Tweedsmuir Park, between 100 and 200 caribou aggregated during the rut in alpine habitat near Wells Gray Peak in the Quanchus Mountains. Rutting groups were also often found in meadows or forest/meadow complexes in the eastern part of northern Tweedsmuir Park. Although up to 40% of radiocollared 83 caribou cows did not join these aggregations and remained dispersed throughout northern Tweedsmuir Park, the high pregnancy rate for the population (Cichowski 1989) indicates that females bred even though they did not join large rutting aggregations. Caribou used primarily alpine or subalpine habitat during the rut in the Itcha-Ilgachuz-Rainbow Mountains although some caribou were found in the Itcha Lake meadows and adjacent forests. Rutting aggregations of between 4 and 89 caribou occurred throughout the three mountain ranges. Caribou that rutted in the Quanchus Mountains remained there until they corrmenced movement to winter ranges in November. Several studies have shown that caribou initiate movements to winter ranges 1n response to snow accumulation (Eornonds 1988, Hatler 1983, Marshall 1985). In 1985/86 and 1986/87, all radiocollared caribou were found in the wintering area south of Tetachuck Lake by late November. However, in winter 1987/88, snow accumulation was 40-50% of what 1t was during the other years of the study and fall movements were initiated 2-3 weeks later. One radiocollared caribou remained on the north side of Tetachuck Lake until early January and another moved back north across Tetachuck Lake for 2 weeks in December before returning to winter range south of Tetachuck lake. Specific crossing areas were not identified, but in the f a l l , caribou apparently crossed Tetachuck Lake along the length of the lake as well as in the vicinity of Redfern Rapids at the west end of Tetachuck Lake. In the Itcha-Ilgachuz-Rainbow area, fall migration 84 routes were not as well defined as in the Tweedsmuir-Entiako area and appeared to be the shortest routes between surrmer and winter ranges. Winter range For most of the winter, caribou in the Tweedsmuir-Entiako and Itcha-Ilgachuz areas were found primarily in low elevation pine forests. Use of predominantly low elevation forested areas during winter was also documented for woodland caribou in northern British Columbia (Hatler 1986), west-central Alberta (Edmonds and Bloomfield 1984) and the southern Yukon (Farnell and McDonald 1987, Farnell and McDonald 1989). Between 100 and 300 of the approximately 1500 Itcha-Ilgachuz caribou wintered in the northern Ilgachuz Mountains. Rainbow caribou also wintered on windswept slopes in the northern Ilgachuz or northern Rainbow Mountains. In the Tweedsmuir-Entiako area in some years, alpine areas in the Fawnie Mountains were used by some caribou from mid-February to mid-late March. An increase in use of alpine habitat in late winter in Spatsizi Wilderness Park was attributed to less favourable snow conditions at lower elevations (Hatler 1986). Hatler (1986) suggested that during winters of deep snow accumulation, caribou were restricted to using windswept alpine slopes. During the present study, there were no apparent reasons for the difference 1n use of alpine habitat between years. 85 HABITAT SELECTION ON LOW-ELEVATION WINTER RANGES Terrestrial lichen abundance The results support hypothesis 1: that in winter, caribou which were found 1n low elevation forests selected stands where lichens were most abundant and avoided stands with low lichen abundance. In general, caribou selected mature stands on poor quality sites and avoided irrmature stands, especially on relatively good quality growing sites since lichens were not abundant in irrmature stands. During winter months, caribou selected and were found most frequently 1n Dry Lichen/Lichen Moss and Lichen Moss caribou habitat types on the Tweedsmuir-Entiako winter range, and in the mature Dry Lichen/Lichen Moss caribou habitat type on the Itcha-Ilgachuz winter range. The mature Lichen Moss caribou habitat type was also heavily used in the Itcha-Ilgachuz winter range but was not selected disproportionately to its availability. Conversely, the wetter Moss - Dry Lichen/Lichen Moss and Moss/Seepage Forest (/Aspen Forest) caribou habitat types 1n both Tweedsmuir-Entiako and Itcha-Ilgachuz areas were used less frequently than were available. Of all forested caribou habitat units available, terrestrial lichens were most abundant in drier Dry Lichen/Lichen Moss and Lichen Moss units (Clement 1987, B.C.M.O.F. 1989a, 1989b). Consequently, caribou selected caribou habitat types (Dry Lichen/Lichen Moss and Lichen Moss) with the greatest abundance of terrestrial 1ichens. 86 Forest stand characteristics Selection of forest cover types by caribou on both Tweedsmuir-Entiako and Itcha-Ilgachuz-Rainbow winter ranges supports hypothesis 2: that caribou select mature timber types on poor quality growing sites. Terrestrial lichens are slow-growing and are most abundant in mature forests (Hale 1983, Rowe 1984). In both Tweedsmuir-Entiako and Itcha-Ilgachuz winter ranges, caribou selected mature stands and avoided immature stands. Because terrestrial lichens are poor competitors against vascular plants (Hale 1983, Johnson 1981, Kershaw 1977, Rowe 1984), they grow best on low and poor quality growing sites. These poor quality growing sites include sites with sandy soils and areas of cold air ponding, which impair growth potential of trees. On the Itcha-Ilgachuz winter range, caribou selected mature pine forest cover types on low quality growing sites, and on the Tweedsmuir-Entiako winter range caribou selected mature pine forest cover types on low and poor quality sites . Mature pine forest cover types on poor quality sites were also heavily used in the Itcha-Ilgachuz. winter range, but were not selected disproportionately to availability. Mature pine/spruce stands on medium quality growing sites were used less frequently than were available, n general, caribou selected stands on the lowest quality growing sites (low and poor sites) and seldom used stands on higher quality sites (medium sites). 87 Seasonal variation Although caribou were found most often 1n forest stands on low quality growing sites and with abundant terrestrial lichens, habitat selection varied as the winter progressed. Tweedsmuir-Entiako: In the Tweedsmuir-Entiako area, caribou shifted from using mature pine forests on poor and medium sites 1n early winter to using mature pine and pine/spruce stands on medium sites in late winter/early spring. Use of irrmature pine stands decreased over the winter. Lodgepole pine is an early serai species and can occupy dry open sites whereas interior spruce is more shade tolerant and prefers moister habitats (Hosie 1979, Krajina et al. 1982). The shift from open dry sites in winter to moister sites in late winter/early spring was also evident 1n the use of caribou habitat types. During early winter mature Dry Lichen/Lichen Moss, Lichen Moss and Moss - Dry Lichen/Lichen Moss and Dry Lichen/Lichen Moss Ecomosaic units were most heavily used. In late winter mature Moss/Seepage Forest - Aspen Forest and Lichen Moss were most heavily used. This shift in habitat use and selection coincided with a shift in range to the area at and east of the mouth of the Entiako River, and with an increase in the amount of sedges, grasses and forbs in the diet. The area near the mouth of the Entiako River is 100-200 meters lower in elevation than the areas used by caribou in mid winter. Snow cover there was usually patchy and less than snow cover in the rest of the winter range during late winter. Woodland caribou in 88 Alberta (Fuller and Keith 1981, Edmonds and Bloomfield 1984), northern British Columbia (Hatler 1986) and Manitoba (Darby and Pruitt 1984) also sought out green vegetation at lower elevations during late winter/early spring. In Tweedsmuir-Entiako, caribou continued to use arboreal and terrestrial lichens during late winter/early spring, but to a lesser extent since terrestrial lichen availability was limited to eskers and drier sites within the area. Itcha-Ilgachuz: Although Itcha-Ilgachuz caribou did not exhibit the same trend in increasing use of moister habitat types over winter, there was a definite shift in elevation. Snow conditions influenced habitat selection during winter. During late fall/early winter 1n the Itcha-Ilgachuz area, caribou using low elevation winter range selected Fescue Lichen meadows for terrestrial lichen foraging. Terrestrial lichens were more abundant in fescue-lichen meadows than in any other caribou habitat type (Clement 1987). Caribou that used Fescue Lichen habitats during early winter shifted from those areas to forested areas when snow depth at the Moore Creek open habitat snow station exceeded 50 centimeters and predicted caribou sinking depths in the open exceeded 40 centimeters. In 1986/87, use of Fescue Lichen habitat was almost nil even in December at which time snow depth and predicted caribou sinking depth exceeded the above thresholds. In 1987/88, caribou extensively used Fescue Lichen habitat in December probably due to the low snow accumulation. Use of this habitat decreased as snow accumulation 89 Increased. By February, when snow depth in the open snow station exceeded 40 centimeters, caribou no longer used Fescue Lichen meadows. Predicted caribou sinking depth in open habitat exceeded predicted caribou sinking depth 1n forested habitat by 10-15 centimeters during both 1986/87 and 1987/88. Parker et al. (1984) documented that energy expenditure of walking elk increased exponentially with snow depth and sinking depth. Energy expenditure also Increased as a function of snow density. In the Itcha-Ilgachuz area, data suggest that increased energy expenditure due to snow accumulation and decreased snow penetrability did not affect caribou until predicted sinking depth in the wetland snow station reached 40 centimeters. In early winter, although snow accumulation was less in forested areas than in Fescue Lichen meadows, caribou continued to use Fescue Lichen meadows where terrestrial lichens were more abundant than in forested areas, until snow conditions apparently made it energetically favourable to choose forested habitats over Fescue Lichen meadows. In late winter/early spring, caribou used lower elevation forested habitats in SBPSxc in the area south of Punkutlaenkut Creek. By this time caribou were presumably foraging on bare patches to obtain green vegetation. 90 WINTER FEEDING ECOLOGY Cratering versus arboreal lichen feeding Caribou in both Tweedsmuir-Ent1ako and Itcha-Ilgachuz winter ranges fed primarily by digging through the snow to obtain terrestrial lichens. Within forested habitat, terrestrial lichen feeding sites made up 78% of feeding sites 1n the Itcha-Ilgachuz area and 63% of the feeding sites 1n the Tweedsmuir-Entiako area. In general, caribou appeared to obtain more forage from craters than from arboreal lichen feeding. Data from feeding sites therefore probably underestimated the importance of terrestrial lichens. Fecal fragment data also suggested that terrestrial lichens were used more than arboreal lichen; however, the difference between the two types of foraging 1s not as apparent as with the feeding site data. Fecal fragment analysis assumes that plant fragments present in feces are proportional to the forages ingested (Holechek et al. 1982); however, different forage Items are digested at different rates (Person et al. 1980a, Person et al. 1980b, Thomas et al. 1984, Thomas and Kroeger 1981, Trudel1 et al. 1980). Because of the problems associated with fecal fragment analysis, in this study it was used only to describe general trends in diet. Arboreal lichen feeding was more pronounced in stands on moister sites (pine/spruce, spruce, forested wetlands) where arboreal lichens were more abundant than in stands on drier sites (pine). In pine stands, caribou incidentally grazed some arboreal lichen while travelling, whereas at other sites, especially in forested wetlands, 91 caribou fed extensively on arboreal 1ichen-loaded trees. Arboreal lichens were used to a greater extent in the Tweedsmuir-Entiako area (39% of forest feeding sites) than in the Itcha-Ilgachuz area (21% of forest feeding sites). This difference may be the result of a combination of fewer habitat units containing abundant terrestrial lichens (i.e. Dry Lichen sites) and more habitat containing abundant arboreal lichens (i.e. fringe spruce forests around lakes and wetlands) in Tweedsmuir-Entiako. Use of arboreal lichens in Tweedsmuir-Entiako and Itcha-Ilgachuz was higher than that reported 1n west-central Alberta even during winters of extreme snow accumulation (Edmonds and Bloomfield 1984). Fecal data also indicated a greater degree of use of arboreal lichen in the Tweedsmuir-Entiako and Itcha-Ilgachuz areas than 1n west-central Alberta. Arboreal lichens were used most heavily in both Tweedsmuir-Entiako and Itcha-Ilgachuz areas during late winter (March). Arboreal lichen use by caribou and reindeer increases in importance as winter progresses or during winters of deep snowpack (Bergerud 1974b, Edmonds and Bloomfield 1984, Helle 1981, Sulkava and Helle 1975). The increase in importance of arboreal lichen during late winter was more pronounced in the Tweedsmuir-Entiako winter range than in the Itcha-Ilgachuz winter range. This increase was possibly due to a combination of less habitat with abundant terrestrial lichens and more frequent melt/freeze conditions which impair cratering conditions in the lower elevation Entiako area. Although it might appear that walking between trees to feed on arboreal lichen would be energetically favourable over digging through snow to obtain terrestrial lichens, the energetic cost of cratering in 92 loose or thinly crusted snow is less than the energetic cost of a slow walk on a treadmill (Fancy and White 1985). The energetic expenditure of travelling from tree to tree in soft snow would therefore be greater than that of cratering. Caribou cratering in loose or thinly crusted snow expend the same amount of energy as caribou foraging in snowfree areas during surrmer (Thing 1977). Cratering during late winter in harder, more crusted snow requires greater energy expenditure than during early and mid winter (Fancy and White 1985, Thing 1977). By late winter, walking over hard snow and feeding on arboreal lichens may become energetically favourable over cratering for terrestrial lichens. Greater use of arboreal lichens in Tweedsmuir-Entiako than Itcha-Ilgachuz suggests that snow conditions in Tweedsmuir-Entiako may be less favourable for cratering than in Itcha-Ilgachuz area. Crater selection Terrestrial lichen abundance: Within forested habitat, crater site selection by caribou supported hypothesis 3: caribou cratered where terrestrial lichens were abundant and seldom cratered where terrestrial lichens were absent or present in low quantities. Caribou in both Tweedsmuir-Entiako and Itcha-Ilgachuz areas cratered most often in pine stands and much less often on moister sites in pine/spruce, spruce and forested wetlands. Terrestrial lichen abundance is greater on dry, nutrient-poor, open sites (Clement 1987). On moister sites, competition from vascular plants limits terrestrial lichen growth (Johnson 1981, Kershaw 1977). 93 Terrestrial lichens were more abundant at craters than at non-crater sites and craters were also more frequent in relatively open canopies than in closed canopies. In general, caribou selected sites with abundant terrestrial lichens. Those sites tended to have sparse canopies because they were poor growing sites. Snow conditions: Within forested habitat, snow depth data did not support hypothesis 4: that caribou crater where snow depth is lower and/or snow penetrability is greater. During most of the winter, snow depth and snow penetrability in forested areas were similar at craters and non-crater sites. Where snow depth and penetrability did differ between crater and non-crater sites, snow depth and snow penetrability were greater at craters than at non-crater sites. On other woodland caribou, reindeer and barren-ground caribou winter ranges, snow depth at non-crater sites exceeded snow depth at craters (Adamczewski et al. 1988, Bergerud 1974b, Henshaw 1968, Laperriere and Lent 1977, Pruitt 1959, Skogland 1978). In the present study, greater snow depths at crater sites than non-crater sites reflected selection of sites with greater lichen abundance. Those sites occurred in open stands which intercepted less snow. Snow accumulation did not prevent caribou cratering in forested habitats. Caribou cratered in up to 75 centimeters of snow. In 1986/87, almost all craters on the Itcha-Ilgachuz winter range during February and March were greater than 50 centimeters deep. Stardom 94 (1975) suggested a threshold of 65 centimeters for caribou cratering 1n forested winter habitats. However, woodland caribou in west-central Alberta cratered in up to 100 centimeters of snow during a heavy snow year 1981/82 (Edmonds and Bloomfield 1984). Helle (1981) reported crater depths up to 88 centimeters for reindeer in Finland and Bergerud (1974b) observed craters in up to 74 centimeters of snow for caribou in Newfoundland. Pruitt (1959) suggested a threshold of 60 centimeters for barren-ground caribou on tundra range and Henshaw (1968) observed that barren ground caribou would not dig for food in more than 70 centimeters of snow and only rarely dug in more than 50 centimeters of snow. Barren-ground caribou occupying tundra ranges would encounter greater snow density and hardness than woodland caribou using forested habitats since forested areas are protected from wind action. Also, woodland caribou are larger animals and would be able to crater in deeper snow than barren-ground caribou. Bergerud (1974b) also observed that woodland caribou did not use areas with snowpacks of greater than 90 centimeters. During the present study, snow depth exceeded 90 centimeters only in open habitat, but caribou had ceased using those habitats when snow depth exceeded 50 centimeters. Snow penetrability also had l i t t l e effect on crater site selection; however, snowpack was unusually low the year snow penetrability was examined. On barren-ground caribou ranges, snow penetrability had a much greater effect on crater site selection at deeper snow depths (Henshaw 1968, Pruitt 1959). In Tweedsmuir-Entiako as snow depth increased and snow penetrability decreased in late winter, caribou selected crater sites with greater snow penetrability, 95 suggesting that snow penetrability may potentially play a greater role in crater site selection during winters of greater snow accumulation. Microsite detection: The major factor influencing crater site selection by caribou in forested areas was terrestrial lichen abundance. In Finland, Helle (1981) found that reindeer could smell lichens in up to 70 centimeters of show. Caribou in both Tweedsmuir-Entiako and Itcha-Ilgachuz areas most likely detected lichens by smelling them. Snow depth, snow penetrability and canopy cover were Inconsistent between sites and any differences were likely characteristics of mlcrosites associated with terrestrial lichen abundance rather than environmental cues used to detect lichens. IMPLICATIONS TO FORESTRY The previous sections discussed caribou use of individual resource levels. To identify possible effects of logging on caribou, information on seasonal movements, habitat use, feeding site characteristics and forage selection must be integrated to determine relations between caribou and their seasonal habitats. 96 Surrmer range Although some calving occurs in the mountains west of northern Tweedsmuir Park and some rutting occurs east of the northern Tweedsmuir Park boundary, surrmer ranges (including calving and rutting areas) of Tweedsmuir-Entiako and Rainbow Mountain caribou occur almost exclusively within Tweedsmuir Park. Outside of the park, calving occurs in alpine habitat, and rutting occurs in forest/meadow/lake complexes irrmedlately adjacent to northeastern Tweedsmuir Park. These calving and rutting areas are not directly threatened by logging due to the nature of the habitats used. In the Itcha-Ilgachuz area, caribou surrmer in the Itcha and Ilgachuz Mountains in alpine habitat and adjacent forests. Currently, a proposal has been submitted to make this area into a Wildlife Management Area. Because caribou use primarily alpine habitats in surrmer, logging will have l i t t l e direct impact on caribou surrmer habitat; however, logging roads could increase access to and disturbance on calving grounds. Winter range Logging has a much greater potential impact on caribou winter ranges than on surrmer ranges. During winter, caribou generally select low elevation forested habitats where snow accumulated at a slower rate than in open habitats or at higher elevations. Mature pine forests were most frequently selected. Within these pine forests, feeding sites were chosen on the basis of terrestrial lichen availability and abundance. Arboreal lichens were also used during winter but to a lesser extent 97 than terrestrial lichens. Lichens are slow growing and are most abundant in mature forests (Hale 1983, Rowe 1984). On the Tweedsmuir-Entiako and Itcha-Ilgachuz winter ranges, caribou selected mature stands and avoided irrmature stands. Consequently, normal forest rotations are inconsistent with protecting caribou winter habitat and adequate amounts of good habitat must be protected if caribou are to be maintained. Characteristics of high quality caribou winter habitat would therefore include: mature forested stands (primarily pine stands); well drained soils and open canopy supporting abundant terrestrial lichen conrmunltles while providing sufficient snow interception; moderate to high quantities of arboreal lichens; and moderate quantities of other vegetation. Recently, logging activity has increased in the peripheries of the Itcha-Ilgachuz and Tweedsmuir-Entiako winter ranges. Most of both winter ranges however, remain pristine with occasional seismic lines transecting the Itcha-Ilgachuz area. Timber harvest affects woodland caribou habitat directly by destroying terrestrial and arboreal lichens. Preferred terrestrial lichen species such as Cladina spp. are late successional species (Ahti 1977, Carroll and Bliss 1982, Johnson 1981, Rowe 1984, Appendix IV). Regeneration of lichens to pre-logging levels would take at least 50-100 years due to succession and to slow lichen growth rates (Hale 1983, Rowe 1984). In terms of lichen supply, logged areas would be unavailable to caribou for at least 50 years. Therefore, sufficient mature forested habitat must be maintained to provide an adequate winter food supply. During winter, caribou in both Tweedsmuir-Entiako and Itcha-Ilgachuz areas primarily used mature pine stands on 98 low or poor quality growing sites where terrestrial lichens were most abundant. In terms of caribou habitat types, Dry Lichen/Lichen Moss and Lichen Moss were most frequently used. Timber on these sites would be of lower merchantable value than on moister and more productive sites that were seldom used by caribou. Much of the best caribou habitat therefore, occurred on poor growing sites with low timber values such as Dry Lichen/Lichen Moss sites. However, Lichen Moss sites, which have higher timber values, were also important caribou habitat and should be managed as high quality caribou winter habitat. During winters of above average snowfall, arboreal lichens may become more important than terrestrial lichens as winter forage. Arboreal lichens occurred throughout forested areas but were most abundant (especially in Tweedsmuir-Entiako) surrounding lakes and wetlands. In Tweedsmuir-Entiako, spruce/wet land/lake ecomosaics were an example of such habitats. The combination of high arboreal lichen abundance and less snow accumulation due to denser canopies probably make these valuable habitats during periods of adverse snow conditions. Wetlands in the Itcha-Ilgachuz winter range and lakes in the Tweedsmuir-Entiako winter range were heavily used for obtaining slush and free water. Maintaining lichen bearing buffers surrounding lakes and wetlands would both provide abundant arboreal lichen forage during winters of high snowfall, and maintain visual barriers between roads and wet1ands. 99 During late winter/early spring, caribou in both Itcha-Ilgachuz and Tweedsmuir-Entiako winter ranges used snowfree areas at lower elevations in which to forage. Clearcuts in those areas may provide green vegetation and early snowfree areas. Similarly, during spring migration caribou used low elevation forested areas relatively free of snow. Small clearcuts may be used by caribou in spring. Tweedsmuir-Entiako caribou were found bedded down less than 10 meters away from clearcuts on the north side of Natalkuz Lake during late winter/early spring. Itcha-Ilgachuz caribou were found in clearcuts as well as bedded down close to them in late winter/early spring when clearcuts were free of snow, suggesting that caribou may have been using those areas. Caribou avoided inrmature forest stands, and large tracts of dense second-growth stands may impede migration. Therefore, timber harvests should be scheduled so that there is always a continuum of mature forests along migration routes. Logging roads may be used by caribou during spring migration if roads run in the same direction as migration routes and if traffic is minimal or nonexistent during spring migration. Indirect effects of logging may be more detrimental to caribou populations than the direct result of destruction of winter food supply. New logging roads provide improved access into wilderness areas which previously were difficult to reach. Although the physical presence of roads themselves is.not detrimental to caribou (Bergerud et al. 1984b, Gauthier et al. 1976, Russell and Marten 1976, Skogland 1986), improved access generally results in increased human use of an area. In well roaded caribou ranges in west-central Alberta (Edmonds and Bloomfield 100 1984) and southeastern British Columbia (Simpson et al. 1987), poaching accounted for a large proportion of caribou mortality (Bergerud 1974a). Because caribou are gregarious and use open habitat, increased access can result in a substantial increase in hunting and poaching mortality (Bergerud et al. 1984b). Logging can therefore indirectly affect caribou numbers through increased access and poaching. Another indirect effect of logging on caribou numbers is the decreased amount of mature forest which caribou can occupy, thereby ar t i f i c i a l l y increasing the density of caribou in the remaining mature stands. An antipredator strategy of woodland caribou is to exist at low densities; that is to space themselves out so that it is harder for predators to find them (Bergerud et al. 1984b, Bergerud and Page 1987). When caribou populations grow, they use a larger area to maintain low densities instead of increasing the density in the area already occupied (Bergerud et al. 1984b). In Ontario, logging in woodland caribou winter ranges effectively restricted animals to using remaining mature stands (Darby and Duquette 1986). By concentrating caribou into smaller areas of mature forests, logging can indirectly increase predator efficiency. Logging, like fire, reverts mature forest into early successional stages, creating habitat favoured for moose (Peek 1974). A corresponding increase in moose numbers provides an increase in an alternate prey base for predators, which in turn can support a larger predator population. The greater number of predators exert greater predation pressure on caribou. Because caribou have low reproductive rates, an increase in predation pressure on caribou may cause the 101 caribou population to decline. Since there will be an alternate prey available (moose) to sustain predator numbers, the combination of low reproductive rates and an increase in caribou mortality due to predation, can lead to a population decline. In Quesnel Highlands, wolves (Canis lupus) are sustained by moose living 1n valley bottoms 1n winter (Seip 1989). In spring and surrrner, wolves follow moose into higher elevations bringing them into closer contact with caribou. Current low calf recruitment and high adult mortality due to wolf predation in that area will likely lead to caribou extinction because wolves are sustained by moose (Seip 1989). Similarly, Darby and Duquette (1986) suggested that 1n Ontario, woodland caribou use of only unlogged portions of their winter range may have resulted Indirectly from increased deer numbers (alternate prey for wolves) in logged areas. Effects of logging on caribou in Tweedsmuir-Entiako and Itcha-Ilgachuz -Rainbow areas will be manifested both directly and indirectly. A decrease in the food supply, increased access, decreased space and potentially disturbed predator-prey relationships combined will generally affect the caribou populations negatively. Forestry practices must be consistent with caribou winter food and spatial requirements. Access control will become increasingly important as logging approaches caribou rutting areas in large open habitats, where caribou are vulnerable to hunting. Finally predator-prey relationships may need to be managed to ensure adequate survival rates. SUMMARY 1. Tweedsmuir-Entiako caribou migrated north across Tetachuck Lake in early May, then moved through low elevation forested and meadow habitats to calving areas throughout northern Tweedsmuir Park and the mountains west of the park. Caribou were widely distributed during the surrmer and habitat use ranged from Coastal Western Hemlock forests at 500 meters to alpine habitats at 2000 meters. In October, caribou began moving east towards the Quanchus Mountains and Tetachuck Lake. Rutting occurred throughout the park, but major rutting aggregations were found in alpine habitat near Wells Gray peak and in forest/meadow complexes east of the Quanchus Mountains. By early December caribou had moved south across Tetachuck Lake and used primarily low elevation pine or pine/spruce forests throughout the winter. Some years, between mid February and mid March, part of the population used alpine and subalpine habitats in the Fawnie Mountains. In March, caribou at lower elevations concentrated near the mouth of the Entiako River where they used pine and pine/spruce forests, before moving to the south side of Tetachuck Lake. 2. In May, Itcha-Ilgachuz caribou moved from late winter ranges to high elevation forested and meadow habitats at the base of the Itcha and Ilgachuz Mountains and in the pass between the two ranges. In early June, calving occurred at high elevations in alpine habitat. Radiocollared caribou surrmered primarily in alpine habitat in the Itcha-Ilgachuz Mountains but also in forested and meadow habitats adjacent to the mountains. During October, radiocollared caribou used mostly alpine 103 habitat and subalpine or forested-meadow complexes. Caribou began moving to winter ranges in November, and during early winter used both pine forests and high elevation, dry Fescue-lichen meadows. During winter radiocollared caribou were found primarily in low elevation pine forests, although some of the animals remained 1n the alpine on the north side of the Ilgachuz Mountains. 3. Radiocollared Rainbow caribou concentrated on the north side of the Rainbow Mountains in May. Caribou were widely distributed throughout alpine habitat in the Rainbow Mountains during surmer and early f a l l . Caribou that remained in the Rainbow Mountains during the winter were found primarily in alpine habitat on the north slopes. Some of the radiocollared caribou moved to the north side of the Ilgachuz Mountains in November and followed the same habitat use patterns as the Itcha-Ilgachuz caribou that wintered there. Caribou that wintered in the Ilgachuz Mountains returned to the Rainbow Mountains by May. 4. Overall, during winter caribou in both Tweedsmuir-Entiako and Itcha-Ilgachuz low elevation winter ranges used predominantly mature pine forest cover types on low and poor quality sites, and mature Dry Lichen/Lichen Moss and Lichen Moss caribou habitat types. In early winter Itcha-Ilgachuz caribou selected Fescue Lichen meadows but stopped using them by February due to deep snow accumulation. By late winter, Tweedsmuir-Entiako caribou were found near the mouth of the Entiako River using mature Moss/Seepage Forest - Aspen Forest caribou habitat types and selected mature pine and pine/spruce forest cover types on medium quality sites. In the Itcha-Ilgachuz winter range during late 104 winter, Dry Lichen/Kinnikinnick sites in the SBPSxc biogeoclimatic subzone south of Punkutlaenkut Creek were also heavily used. 5. Snow depth affected habitat selection by caribou. In early winter Itcha-Ilgachuz caribou used both Fescue Lichen meadows and pine forests. When snow depth and predicted caribou sinking depth approached 50 and 40 centimeters respectively in the Moore Creek wetland snow station, use of Fescue Lichen meadows ceased and caribou were found primarily in forested habitats. 6. In low elevation winter ranges in the Tweedsmuir-Entiako and Itcha-Ilgachuz areas, caribou foraged primarily by cratering for terrestrial lichens in pine forests. Within forested habitats feeding si t e selection was dependent on terrestrial lichen presence and abundance. Snow depth did not appear to affect feeding s i t e selection. Snow depth was often greater at crater sites than at non-crater sites, most l i k e l y because sites with high terrestrial lichen abundance had more open canopies which intercepted less snow. Snow penetrability did not appear to influence crater s i t e selection in 1987/88; however, data suggested that snow penetrability may have a greater Influence during years with deeper snowpacks and lower snow penetrability. Arboreal lichen feeding also occurred in pine forests but arboreal lichen feeding was more prevalent in pine/spruce or spruce forests and forested wetlands. In the Itcha-Ilgachuz area, caribou obtained slush/free water in wetlands and to a lesser extent on creeks, and in the Tweedsmuir-Entiako area, caribou obtained slush/free water on lakes and creeks. 105 7. Direct effects of logging on woodland caribou in west-central British Columbia should be minimized easily. It will be important to protect mature forest stands with abundant terrestrial lichens because lichen regeneration i s slow. However, because terrestrial lichens are most abundant on poor growing sites, the best caribou habitat occurs on low quality timber sites. Indirect effects of logging through increased access, decreased space and disturbed predator-prey relationships may also have great effects on both Tweedsmuir-Entiako and Itcha-Ilgachuz-Rainbow caribou populations. 106 MANAGEMENT RECOMMEN0ATI0NS 1. Large undisturbed areas should be maintained for calving and surrmer ranges throughout which caribou may distance themselves from each other and from other prey or predator species. Undisturbed areas such as Tweedsmuir Park and the proposed Itcha-Ilgachuz Wi l d l i f e Management Area will be important for maintaining this objective. 2. In the Chelaslie River drainage i t 1s important to maintain the low elevation spring migration routes of the caribou. Large clearcuts and/or extensive tracts of dense second-growth may inhibit migration. 3. The prime winter range areas where habitat protection i s most important include: Tweedsmuir-Ent1ako: -the Entiako River drainage, southwest of Capoose Creek -the area at the southeast end of Bryan Arm of Tetachuck Lake Itcha-Ilgachuz-Rainbow -the east side of the Chllcotin River, south of Baldface Mountain to the junction with Downton Creek -the Downton Creek drainage -the north side of Punkutlaenkut Creek, just north of Satah Mountain -the south side of Punkutlaenkut Creek east of Satah Mountain -low elevation forests north of the Ilgachuz Mountains 107 4. Because caribou require abundant lichens which are not provided during normal forest rotations, sufficient mature forest must be protected from logging i f caribou are to be maintained. The habitat types that are most important to protect are: -Dry Lichen/Lichen Moss and Lichen Moss caribou habitat types -mature pine forest cover types on low and poor quality sites 5. Effects of logging on terrestrial lichens should be determined for both sunrmer and winter logging. If no difference i s found, most logging should occur during surmer months to minimize human contact with caribou. If winter logging reduces destruction of terrestrial lichens, the potential of clearcuts and young stands for winter use by caribou must be assessed before reccmriending winter logging. 6. Controlling access within winter ranges would reduce potential disturbance, displacement and poaching of caribou. 7. Productivity and reforestation problems on these poor growing sites should be re-evaluated. Given the low productivity of these sites in the Tweedsmuir-Entiako and Itcha-Ilgachuz areas, caribou winter habitat values may exceed timber harvest values. LITERATURE CITED Adamczewski, J.Z., CC. 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Direktoratet for v l l t og ferskvannsfisk, Trondheim. 799p. APPENDIX I SUMMARY OF RADIOCOLLARED CARIBOU LOCATIONS IN EACH HABITAT TYPE, CARIBOU HABITAT TYPE AND FOREST COVER TYPE BY AREA, SEASON AND YEAR Table 1. Mean monthly elevation (in meters above sea level) of radiocollared caribou locations in the Tweedsmuir-Entiako, Itcha-Ilgachuz and Rainbow study areas. Standard 1 Standard N Mean Deviation Deviation Tweedsmuir-Ent1ako Apri 1 78 972 106 866-1078 May 50 1062 136 927-1198 June (Alpine) 22 1533 189 1344-1722 June (Below treeline) 30 1107 181 926-1288 July (Alpine) 19 1486 274 1213-1760 July (Below treeline) 34 1001 130 871-1132 August 40 987 240 747-1227 September 49 1129 212 918-1341 October (Alpine) 26 1529 154 1376-1683 October (Below treeline) 28 1183 186 997-1369 November (Alpine) 15 1584 126 1459-1710 November (Below treeline) 20 1013 123 889-1136 December 110 1048 128 919-1176 January 132 993 104 890-1097 February (Alpine) 9 1619 72 1547-1691 February (Below treeline) 161 993 70 923-1062 March (Alpine) 30 1641 201 1440-1842 March (Below treeline) 136 989 81 908-1070 Itcha-Ilgachuz April (Alpine) 7 1897 81 1816-1979 April (Below treeline) 45 1292 73 1219-1365 May (Alpine) 23 1788 193 1595-1981 May (Below treeline) 56 1466 121 1345-1586 June 39 1885 120 1766-2005 July 56 1839 142 1697-1981 August 61 1706 150 1556-1856 September 47 1722 141 1581-1863 October 56 1821 136 1685-1956 November 31 1625 139 1486-1764 December 108 1499 128 1371-1627 January (Alpine) 13 1630 181 1449-1811 January (Below treeline) 105 1447 93 1354-1539 February (Alpine) 14 1761 176 1586-1937 February (Below treeline) 134 1427 86 1342-1513 March (Alpine) 19 1751 168 1583-1918 March (Below treeline) 142 1382 98 1284-1481 1 1 7 Rainbow Apri 1 21 1894 66 1829-1960 May 31 1911 193 1718-2105 June 17 1837 134 1704-1971 July 21 1802 128 1674-1930 August 24 1819 159 1660-1979 September 20 1854 84 1769-1938 October 20 1874 150 1724-2024 November 18 1819 150 1670-1969 December (Alpine) 39 1845 166 1679-2011 December (Below treeline) 7 1514 128 1386-1643 January (Alpine) 34 1848 149 1698-1997 January (Below treeline) 12 1381 172 1209-1553 February (Alpine) 52 1896 170 1727-2066 February (Below tree!ine) 18 1280 173 1107-1453 March (Alpine) 49 1956 166 1789-2122 March (Below tree!ine) 7 1283 96 1187-1379 118 Table 2. Proportion of radiocollared caribou locations in each habitat type in the Tweedsmuir-Entiako study area (April 1985 - March 1988). Habitat April -Type May June - July 15 -July 14 Septernber October November December -March Pine 1985/86 1986/87 1987/88 Total .450(18) .750(18) .597(46) .581(82) (0) .273(6) .091(3) .132(9) .333(4) .262(11) .099(7) .176(22) .071 (1) (0) (0) .020(1 ) .636(7) (0) .214(3) .244(10) .565 (78) .581 (129) .714 (155) .627 (362) Spruce 1985/86 1986/87 1987/88 Total .025(1) (0) .065(5) .043(6) .231 (3) .182(4) .061(2) .132(9) .250(3) .166(7) .113(8) .144(18) (0) .286(6) .214(3) .184(9) (0) (0) (0) (6) .073 (10) .023 (5) .014 (3) .031 (18) Pine/Spruce 1985/86 .275(11) .154(2) (0) .143(2) (0) .218 (30) 1986/87 .167(4) .182(4) .143(6) .048(1) (0) .081 (18) 1987/88 .208(16) .152(5) .239(17) .143(2) .071(1) .106 (23) Total .220(31) .162(11) .184(23) .102(5) .024(1) . 123 (71 ) Pine/Meadow 1985/86 (0) (0) .333(4) .143(2) .182(2) .036 (5) 1986/87 (0) .136(3) .214(9) .143(3) .125(2) .014 (3) 1987/88 .013(1) (0) (0) (0) (0) (0) Total .007(1 ) .044(3) .104(13) .102(5) .098(4) .014 (8) Spruce/Meadow 1985/86 .125(5) .077(1) (0) (0) .091(1) .029 (4) 1986/87 (0) (0) .024(1) .095(2) (0) .014 (3) 1987/88 .013(1) (0) .014(1) (0) (0) .018 (4) Total .043(6) .016(1) .016(2) .041(2) . 024"(1) .019 (11) P i ne-Spr uce/Meadow 1985/86 .050(2) 1986/87 1987/88 Total .042(1) .013(1 ) .028(4) (0) (0) (0) (0) (0) .024(1 ) (0) .008(1 ) (0) .190(4) (0) .682(4) ,091 (1) (0) (0) .024(1 ) .036 (5) .054 (12) (0) .629 (17) Meadow 1985/86 1986/87 1987/88 Total .025(1) (0) .065(5) .043(6) .308(4) (0) .061(2) .088(6) (0) (0) .028(2) .016(2) (0) .048 (1 ) (0) .020(1) (0) .250(4) (0) .698(4) .007 (1) .009 (2) .010 (2) .669 (5) 119 Subalpine 1985/86 1986/87 1987/88 to ta l .025 (1) (0) ,026(2) .021 (3) (0) (0) ,273(9) .132(9) .083(1 ) .048(2) .113(8) .088(11> .286(4) (0) .429(6) .204(10) (0) .062(1 ) .214(3) .098(4) .007 (1) .063 (14) .106 (23) .066 (38) A lp ine 1985/86 1986/87 1987/88 Total .025(1) (0) (0) .007 (1 ) .231(3) .227(5) .364(12) .294(20) (0) .119(5) .070(5) .080(10) .357(5) .190(4) .143(2) .225(11) (0) .563(9) .500(7) ,390(16) (0) .108 (24) (0) .042 (24) Lake 1985/86 1986/87 1987/88 Total (0) .042(1) (0) .007(1) (0) (0) (0) (0) (0) (0) (0) (6) (0) (0) (0) (0) (0) (0) (0) (0) .029 (4) .054 (12) .032 (7) .040 (23) Coastal Western Hemlock 1985/86 (0) (0) (0) 1986/87 (0) (0) (0) 1987/88 (0) (0) .042(3) Total (0) (0) .024(3) (0) (0) (0) (0> (0) (0) (0) (0) (0) (0) (0) (6) Mountain Hemlock 1985/86 (0) 1986/87 (0) 1987/88 (0) Total (6) (0) (0) (0) (6) (0) (0) .282(20) .160(20) (0) (0) .071 (1 ) .020(1 ) (0) (0) (0) (0) (0) (0) (0) (6) TOTAL # LOCATIONS 1985/86 40 1986/87 24 1987/88 77 Total 141 13 22 33 68 12 42 71 125 14 21 14 49 11 16 14 41 138 222 217 577 120 Table 3. P ropor t ion of r a d i o c o l l a r e d c a r i b o u l o c a t i o n s 1n each hab i ta t type i n the I tcha- I lgachuz study area ( A p r i l 1985 - March 1988) Habi ta t A p r i l -Type May June - J u l y 15 -J u l y 14 September October November December • March Pine 1985/86 1986/87 1987/88 Total .343(12) .522(23) .615(32) .511(67) (0) (0) .038 (1 ) .015(1) .103(3) .213(10) .109(7) .143(20) .095(2) .091(2) (0) .071(4) .200(2) .636(7) .250(3) .363(12) .817 (116) .718 (148) .702 (132) .739 (396) P ine /Spruce 1985/86 (0) 1986/87 .023(1) 1987/88 (p) Tota l .668(1) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (6) .014 .010 .007 (2) (2) (0) (4) P1ne/Meadow 1985/86 .343(12) 1986/87 .045(2) 1987/88 .020(1) Tota l .114(15) (0) (0) (0) (0) .207(6) .128(6) .016(1) .093(13) .048 (1 ) (0) (0) .018(1) .400(4) .091 (1 ) (0) .152(5) .120 (17) .010 (2) .006 (1) .037 (20) Spruce/Meadow 1985/86 (0) 1986/87 .023(1) 1987/88 (0) Tota l .668(1) (0) (0) (0) (0) (0) (0) (0) 16) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) Pine - Spruce/Meadow 1985/86 1986/87 1987/88 Tota l (0) ,023(1) (0) .008(1 ) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (6) .014 (2) .005 (1) (0) .006 (3) Meadow 1985/86 1986/87 1987/88 Tota l .029(1) .205(9) .077(4) .107(14) (0) (0) (0) (6) .138(4) (0) .031(2) .643(6) .095(2) (0) (0) ,036(2) .400(4) .091 (1 > .170(2) .212(7) .035 (5) .034 (7) .138 (26) .071 (38) Subalp ine 1985/86 1986/87 1987/88 Tota l .114(4) .068(3) .096(5) .091(12) .167(2) (0) .077(2) .061(4) .414(12) .276(13) .375(24) .350(49) .381(8) .273(6) (0) .250(14) (0) .182(2) .250(3) .152(5) (0) ,126 (26) .085 (16) ,078 (42) 121 Alpine 1985/86 .171(6) 0. 833(10) .138(4) 0.381(8) (0) (0) 1986/87 .068(3) 1 . 000(28) .383(18) 0.636(14) (0) .082 (17) 1987/88 .190(10) 0. 885(23) .469(30) 1.000(13) .330(4) .037 (7) Total .145(19) 0. 924(61) .371(52) 0.625(35) .121(4) .045 (24) Lake 1985/86 (0) (0) (0) (0) (0) (0) 1986/87 (0) (0) (0) (0) (0) .015 (3) 1987/88 (0) (0) (0) (0) (0) .032 (6) Total (0) (0) (0) (0) (0) .017 (9) Clearcut 1985/86 (0) (0) (0) (0) (0) (0) 1986/87 .023(1 ) (0) (0) (0) (0) (0) 1987/88 (0) (0) (0) (0) (0) (0) Total .008(1) (0) (0) (0) (0) (0) TOTAL # LOCATIONS 1985/86 35 12 29 21 10 142 1986/87 44 28 47 22 11 206 1987/88 52 26 64 13 12 188 Total 131 66 140 56 33 536 122 Table 4. P r o p o r t i o n of r a d i o c o l l a r e d c a r i b o u l o c a t i o n s 1n each h a b i t a t type i n the Rainbow study area ( A p r i l 1985 - March 1988). Ha b i t a t A p r i l -Type May June - J u l y 15 - December-J u l y 14 September October November March Pine 1985/86 1986/87 1987/88 To t a l (0) (0) (0) (6) (0) (0) (0) (6) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) .275 (11) .009 (1) .297 (19) .144 (31) Pine/Spruce 1985/86 (0) 1986/87 .071(1) 1987/88 (0) To t a l .019(1) (.0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) .050 .031 .019 (2) (0) (2) (4) Pine/Meadow 1985/86 (0) 1986/87 (0) 1987/88 (0) To t a l (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) .250(1) (0) (0) .071 (1 ) ,025 ,009 ,009 (1 ) (1 ) (0) (2) Pine - Spruce/Meadow 1985/86 1986/87 1987/88 Tot a l (0) (0) (0) (6) (0) (0) (0) (6) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) ,025 ,005 (1) (0) (0) (1 ) Meadow 1985/86 1986/87 1987/88 Total (0) (0) (0) (6) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) (0) .025 ,031 .014 (1 ) (0) (2) (3) Subalpine 1985/86 1986/87 1987/88 Total .200(2) (0) (0) .039(2) (0) (0) (0) (6) .429(3) .146(3) ,042 (1 ) .132(7) (0) (0) (0) (0) .250(1) (0) (0) .071(1) .075 (3) .027 (3) ,344 (22) ,130 (28) A l p i n e 1985/86 1986/87 1987/88 Total 0.800(8) 1.000(4) .571(4) 1.000(4) 0.500(2) .525 (21) 0.929(13) 1.000(11) .864(19) 1.000(12) 1.000(6) .955(106) 1.000(28) 1.000(14) .958(23) 1.000(4) 1.000(4) .281 (18) 0.942(49) 1.000(29) .868(46) 1.000(20) 0.858(12) .674 (145) 123 Lake 1985/86 1986/87 1987/88 Total (0) (0) (0) (6) (0) (0) (0) (6) (0) (0) (0) (6) (0) (0) (0) (0) (0) (0) (0) (6j (0) (0) ..•016 (1) . 005 (1 ) TOTAL # LOCATIONS 1985/86 10 1986/87 14 1987/88 28 Total 52 4 11 14 29 7 22 24 53 4 12 4 20 4 6 4 14 40 111 64 215 124 Table 5. Number of r a d i o c o l l a r e d c a r i b o u l o c a t i o n s 1n each f o r e s t cover type c l a s s i n the Tweedsmuir-Entiako and It c h a - I l g a c h u z study areas d u r i n g w i n t e r (December 1, 1986 - March 31, 1987, November 29, 1987 - March 31, 1988). Tree Age Site Species Class Type 1986/87 1987/88 Total TWEEDSMUIR-ENTIAKO Pine 1-4 L + P + M 32 38 70 5-9 L + P 65 73 138 M 35 28 63 Pine/ 1-4 L + P + M 10 0 10 Spruce 5-9 L + P 12 8 20 M 17 18 35 Meadow/Open Range/Wet1 and 3 4 7 Lake 11 7 18 Other 2 3 5 TOTAL 187 179 366 ITCHA-ILGACHUZ Pine 1-4 L 8 6 14 P 20 10 30 5-9 L 66 103 169 P 64 25 89 M 3 10 13 Pine/ 5-9 L + P 14 0 14 Spruce M 4 0 4 Meadow/Open Range/Wetland 4 27 31 Other 3 2 5 TOTAL 186 183 369 Tree Species PINE = Lodgepole p i n e SPRUCE = White spruce + Engelmann spruce + Black spruce Age Classes 1-4 = 0-80 years (Irrmature); 5-9 = >80 years (Mature) Site Types L=Low, P=Poor, M=Med1um Other = Nonproductive (NP) pin e , NP pine/spruce, NP spruce, NP brush, Rock, Irrmature pine (irrmature s i t e s ) ( I I ) , Irrmature pine/spruce ( I I ) , Mature spruce 125 Table 6. Number of radiocollared caribou locations in each forest cover type class in the Tweedsmuir-Entiako study area during early winter (December 1, 1986 - January 6, 1987, November 29, 1987 - January 12, 1988), mid winter (January 16 - March 13, 1987, January 16 - March 11, 1988) and late winter / early spring (March 19 - April 22, 1987, March 16 - March 24, 1988). Tree Age S7te Species Class Type 1986/87 1987/88 Tota" EARLY WINTER Pine 1 -4 L + P + M 11 12 23 5-9 L + P 23 14 37 M 6 4 10 Pine/ 1-4 L + P + M 4 0 4 Spruce 5-9 L + P 2 1 3 M 5 2 7 Meadow/Open Range/Wetland 2 1 3 Lake 2 0 2 Other 1 1 2 TOTAL 56 35 91 MID WINTER Pine 1-4 L + P + M 19 25 44 5-9 L + P 38 50 88 M 20 20 40 Pine/ 1-4 L + P + M 5 0 5 Spruce 5-9 L + P 7 4 11 M 6 10 16 Meadow/Open Range/Wetland 1 3 4 Lake 8 6 14 Other 1 2 3 TOTAL 105 120 225 LATE WINTER Pine 1-4 L + P + M 10 1 11 5-9 L + P 12 9 21 M 21 4 25 Pine/ 1-4 L + P + M 2 0 2 Spruce 5-9 L + P 4 3 7 M 12 6 18 Meadow/Open Range/Wetland 3 0 3 Lake 1 1 2 Other 0 0 0 TOTAL 65 24 89 Tree Species PINE = Lodgepole pine SPRUCE = White spruce + Engelmann spruce + Black spruce Age Classes 1-4 = 0-80 years (Irrmature); 5-9 = >80 years (Mature) S7're Types L=Low, P=Poor, M=Medium Other = Nonproductive (NP) pine, NP pine/spruce, NP spruce, NP brush, Rock, Irrmature spruce, Mature spruce 126 Table 7. Number of radiocollared caribou locations in each forest cover type class in the Itcha-Ilgachuz study area during early winter (November 29, 1986 - January 6, 1987, November 29, 1987 - January 12, 1988), mid winter (January 15 - March 13, 1987, January 16, - March 10, 1988) and late winter/early spring (March 19 - April 22, 1987, March 18 - March 31, 1988). Tree Age Site Species Class Type 1986/87 1987/88 Total EARLY M N T J E R Pine 1-4 L 3 3 6 P 7 2 9 5-9 L 18 20 38 P 23 4 27 M 1 0 1 Pine/ 5-9 L + P 4 0 4 Spruce M 3 0 3 Meadow/Open Range/Wetland 2 22 24 Other 1 0 1 T O T A L 6 2 51 113 MID WINTER Pine 1-4 L 3 3 6 P 9 8 17 5-9 L 37 71 108 P 39 14 53 M 2 7 9 Pine/ 5-9 L + P 10 0 10 Spruce M 1 0 1 Meadow/Open Range/Wetland 2 5 7 Other 1 1 2 TOTAL 104 "109 213 WTLliNTER Pine 1-4 L 2 0 2 P 9 0 9 5-9 L 20 12 32 P 8 7 15 M 1 3 4 Pine/ 5-9 L + P 0 0 0 Spruce M 0 0 0 Meadow/Open Range/Wetland 0 0 0 Other 1 0 1 TOTAL 41 22 63 Tree Species PINE = Lodgepole pine SPRUCE = White spruce + Engelmann spruce + Black spruce Age Classes 1-4 = 0-80 years (Irrmature); 5-9 = >80 years (Mature) S7're Types L=Low, P=Poor, M=Med1un Other = Nonproductive (NP) pine, NP pine/spruce, NP spruce, NP brush, Rock, Immature pine (irrmature sites), jjrmature pine/spruce, Mature spruce 127 Table 8. Number of radiocollared caribou locations in each caribou habitat type category in the Tweedsmuir-Ent1ako and Itcha-Ilgachuz study areas during winter (December 1, 1986 - March 31, 1987, November 29, 1987 - March 31, 1988). 1986/87 1987/88 Total Age Class 0 1-3 4-5 0 1-3 4-5 0 1-3 4-5 Tweedsmuir-Entiako DLLM 7 14 23 30 30 44 LM 9 45 8 47 17 102 DLLMMOSAIC 12 10 7 7 19 17 MDLLM 9 27 1 19 10 46 MSF/AF 1 22 3 18 4 40 W/FW 2 2 2 4 0 1 6 2 3 LAKE 12 7 19 TOTAL 14 40 120 11 42 132 25 82 252 Itcha-Ilgachuz DLLM 1 87 5 91 6 178 LM 9 20 2 37 11 57 DLLMMOSAIC 0 3 2 5 2 8 MDLLM 1 6 0 1 1 7 MSF 0 15 0 3 0 18 W/FW 2 0 2 3 0 2 5 0 4 FL 1 0 0 8 1 16 9 1 16 SBPS-DLK 0 15 0 1 0 16 SBPS-OTHER . 0 3 0 0 _ 0 3 TOTAL 3 11 151 11 10 156 14 21 307 Age Classes 0 = No age class 1-3 = 0-80 years (Irrmature) 4-5 = >80 years (Mature) 128 Table 9. Number of radiocollared caribou locations 1n each caribou habitat type category in the Tweedsmuir-Entiako study area during early winter (December 1, 1986 - January 12,1987, November 29, 1987 - January 12, 1988), mid winter (January 16 - March 13, 1987, January 16, - March 11, 1988) and late winter / early spring (March 19, 1987 - April 22, 1987, March 16-31, 1988). 1986/87 1987/88 Total Age Class 0 1-3 4-5 0 1-3 4-5 0 1-3 4-5 Early winter DLLM 4 6 6 6 10 12 LM 1 10 2 10 3 20 DLLMMOSAIC 4 7 5 4 9 11 MDLLM 2 11 0 4 2 15 MSF/AF 1 3 1 2 2 5 W/FW 1 2 1 1 0 1 2 2 2 LAKE 2 0 2 TOTAL 3 14 38 1 14 27 4 28 65 Mid winter DLLM 5 9 17 24 22 33 LM 5 33 6 42 11 75 DLLMMOSAIC 6 3 3 5 9 8 MDLLM 6 12 3 8 9 20 MSF/AF 0 10 1 3 1 13 W/FW 1 0 1 3 0 1 4 0 2 LAKE 8 6 14 TOTAL 9 22 68 9 30 83 18 52 151 Late winter DLLM 5 4 0 0 5 4 LM 2 15 0 5 2 20 DLLMMOSAIC 0 6 0 0 0 6 MDLLM 3 6 0 5 3 11 MSF/AF 1 18 0 12 1 30 W/FW 0 0 0 0 0 0 0 0 0 LAKE 2 1 3 TOTAL 2 11 49 1 0 22 3 11 71 Age Classes 0 = No age class 1-3 = 0-80 years (Irrmature) 4-5 = >80 years (Mature) 129 Table 10. Number of radiocollared caribou locations 1n each caribou habitat type category 1n the Itcha-Ilgachuz study area during early winter (December 1, 1986 - January 6, 1987, November 29, 1987 - January 12, 1988), mid winter (January 15 - March 13, 1987, January 16 - March 10, 1987) and late winter / early spring (March 19, 1987 - April 22, 1987, March 16 - 24, 1988). 1986/87 1987/88 Total Age Class 0 1-3 4-5 0 1-3 4-5 0 1-3 4-5 Early winter DLLM 1 23 1 17 2 40 LM 2 13 0 6 2 19 DLLMMOSAIC 0 3 0 2 0 5 MDLLM 0 1 0 1 0 2 MSF 0 7 0 1 0 8 W/FW 0 0 2 3 0 1 3 0 3 FL 1 0 0 8 1 9 9 1 9 SBPS-DLK 0 1 0 0 0 1 SBPS-OTHER 0 1 0 0 0 1 TOTAL 1 3 51 11 2 37 12 5 88 Mid winter DLLM 0 56 4 56 4 112 LM 6 8 2 27 8 35 DLLMMOSAIC 0 0 0 4 0 4 MDLLM 1 3 0 0 1 3 MSF 0 8 0 2 0 10 W/FW 2 0 0 0 0 2 2 0 2 FL 0 0 0 0 0 8 0 0 8 SBPS-DLK 0 6 0 1 0 7 SBPS-OTHER 0 0 0 0 0 0 TOTAL 2 7 81 0 6 100 2 13 181 Late winter DLLM 0 14 0 18 0 32 LM 0 2 0 4 0 6 DLLMMOSAIC 0 0 0 0 0 0 MDLLM 0 2 0 0 0 2 MSF 0 1 0 0 0 1 W/FW 0 0 0 0 0 0 0 0 0 FL 0 0 0 0 0 0 0 0 0 SBPS-DLK 0 18 0 0 0 18 SBPS-OTHER 0 3 0 0 0 3 TOTAL 0 0 40 0 0 22 0 0 62 Age Classes 0 = No age class 1-3 = 0-80 years (Irrrnature) 4-5 = >80 years (Mature) APPENDIX II SUMMARY OF DATA USED FOR FEEDING SITE FIGURES Table 1. Number of craters (C) and non-crater sites (NCS) containing abundance classes of terrestrial lichens (0=0%, trace=1%, low=2-14%, mediuiTFl5-39%, high=40-100%) in each habitat type in the Tweedsmuir-Entiako and Itcha-Ilgachuz caribou winter ranges, December 1986 - March 1987, December 1987 - March 1988. % ground cover Pine 0% 1% 2-14% 15-39% 40-100% Total Tweedsmuir-Entiakp C NCS 2 1 35 133 118 289 80 3 29 13 2 127 Itcha-Il C NCS 5 1 85 227 250 568 53 10 59 47 11 180 Spruce 0% 1% 2-14% 15-39% 40-100% Total 2 0 2 2 2 8 19 0 3 1 0 23 Pine/Spruce 0% 1% 2-14% 15-39% 40:100% Total 3 0 7 21 23 54 44 1 14 4 0 63 2 0 0 0 0 2 1 0 4 0 0 5 Total Forest 0% 1% 2-14% 15-39% 40-100% Total 7 1 44 156 143 351 143 4 46 18 2 213 7 1 85 227 250 570 54 10 63 47 11 185 Fescue-Lichen 0% 1% 2-14% 15-39% 40-100% total 0 0 4 18 62 84 0 0 0 0 0 6 Table 2. Number of craters (C) and non-crater s i t e s (NCS) located 1n canopy closure classes (1-5%, 6-10%, 11-15%, 16-20%, >20%) 1n each forested habitat type i n the Tweedsmuir-Entiako and Itcha-Ilgachuz caribou winter ranges, December 1986 - March 1987, December 1987 - March 1988. canopy closure Tweedsmui r-Entiako NCS Itcha-Ilga^ C NCS Pine 1 -5% 6-10% 11-15% 16-20% Total 117 79 52 6 254 13 5 12 2 32 127 226 89 2 444 24 34 38 6 102 Spruce 1 -5% 6-10% 11-15% 16-20% Total Pine/Spruce 1 -5% 6-10% 11-15% 16-20% >20% Total 0 0 0 0 0 39 0 0 0 0 39 3 2 2 0 7 1 3 19 2 1 26 0 1 1 0 0 2 1 0 2 0 0 3 Total Forest I- 5% 6-10% I I - 15% 16-20% >20% Total 156 79 52 6 0 293 17 10 33 4 1 65 127 227 90 2 0 446 25 34 40 6 0 105 133 Table 3. Average snow depth at crater sites (C) and non-crater sites (NCS) in all forested habitat types combined in the Tweedsmuir-Entiako caribou winter range, December 1986 - March 1987, December 1987 - March 1988. 95% Standard Confidence N Mean Deviation Interval 1986/87 January 18, 1987 (C) 49 46.1 6.8 44.2-48.0 (NCS) 63 36.5 6.8 34.8-38.2 January 30, 1987 (C) 2 47.0 4.2 8.9-85.1 (NCS) 58 43.6 8.6 41.4-45.8 February 18, 1987 (C) 5 49.2 6.2 41.5-56.9 (NCS) 3 45.7 9.7 21.6-69.8 March 21, 1987 (C) 0 (NCS) 19 41.3 9.7 36.6-46.0 1987/88 January 13, 1988 (C) 67 16.7 3.6 15.8-17.6 (NCS) 3 16.3 7.6 0-35.1 January 28, 1988 (C) 99 21.0 4.0 20.2-21.8 (NCS) 2 23.5 2. 1 4.4-42.6 February 23, 1988 (C) 74 37.5 5.4 36.3-38.7 (NCS) 15 27.3 8.3 22.7-31.9 March 7, 1988 (C) 39 33.2 3.3 32.2-34.2 (NCS) 16 23. 1 8.8 18.4-27.8 March 17,.1988 (C) 14 32.A 4.8 29.7-35.1 (NCS) 25 26.9 9.0 23.2-30.6 134 Table 4. Average snow depth at crater sites (C) and non-crater sites (NCS) in a l l forested habitat types combined in the Itcha-Ilgachuz caribou winter range, December 1986 - March 1987, December 1987 - March 1988. 95% Standard Confidence N Mean Deviation Interval 1986/87 December 16, 1986 (C) 17 38.4 8.1 36.3-40.5 (NCS) 6 40.2 3.6 36.4-44.0 January 10, 1987 (C) 1 (NCS) 1 January 25, 1987 (C) 27 52.6 6.3 50.1-55.1 (NCS) 29 51.9 5.7 49. 7-54.1 February 6, 1987 (C) 39 58.4 4.5 57.0-60.8 (NCS) 22 52.6 8.3 48.9-56.3 March 3, 1987 (C) 53 56.7 8.7 54.3-59.1 (NCS) 15 53. 7 7. 1 49.8-57.6 March 26, 1987 (C) 5 66.8 7.3 57.8-75.8 (NCS) 13 65. 1 8.6 59.9-70.3 1987/88 December 14, 1987 (C) (NCS) 1 33.0 January 23, 1988 (C) 121 33.8 4.2 33.1-34.5 (NCS) 9 32.6 4. 1 28.5-35.7 February 2, 1988 (C) 143 37.4 3.9 36.7-38.1 (NCS) 7 37.6 3.3 34.6-40.6 February 20, 1988 (C) 60 42.9 5.4 41.5-44.3 (NCS) 31 42.8 5.3 41.0-44.6 March 2, 1988 (C) 99 37.7 5.5 36.6-38.8 (NCS) 39 35.5 6. 1 33.6-37.4 March 20,.1988 (C) 23 33.4 7.7 30.1-36.7 (NCS) 8 29.8 7.9 23.2-36.4 135 Table 5. Average snow penetrability at crater sites (C) and non-crater sites (NCS) in a l l forested habitat types combined in the Tweedsmuir-Ent1ako and Itcha-Ilgachuz caribou winter ranges, December 1987 - March 1988. 95% Standard Confidence N Mean Deviation Interval Tweedsmui r-Ent i ako January 13, 1988 (C) 67 .976 .037 .966-0.986 (NCS) 3 .970 .053 .878-1.062 January 28, 1988 (C) 99 .973 .054 .963-0.983 (NCS) 2 1.000 February 23, 1988 (C) 74 .881 .119 .854-0.908 (NCS) 15 .903 . 124 .835-0.971 March 7, 1988 (C) 39 .948 .055 .930-0.966 (NCS) 16 . 795 . 145 . 719-0.871 March 17, 1988 (C) 14 .863 .092 .809-0.917 (NCS) 25 .696 . 188 .618-0.774 Itcha-Ilgachuz January 23, 1988 (C) 121 .991 .019 .987-0.995 (NCS) 9 1.000 February 2, 1988 (C) 143 .988 .027 .984-0.992 (NCS) 7 .964 .049 .921-1.000 February 20, 1988 (C) 60 .984 .025 .978-0.990 (NCS) 31 .981 .056 .961-1.000 March 2, 1988 (C) 99 .998 .012 .996-1.000 (NCS) 39 .985 .043 .971-0.999 March 20,.1988 (C) 23 .981 .041 .962-1.000 (NCS) 8 .933 . 190 . 778-1.088 136 Table 6. Average snow depth at snow stations in 3 habitat types (wetland, mature and immature pine stands 1n the Itcha-Ilgachuz winter range, January - March 1986, December 1986 -March 1987, December 1987 - March 1988. (Only winter 1986/87 and 1987/88 measurements were taken at established snow stations. Habi tat type 1985/86 N Mean Standard Deviation 95% Confidence Interval Mature Pine January 22,1986 19 February 6, 1986 29 February 24, 1986 29 March 15, 1986 22 Wetland January 22, 1986 13 February 6, 1986 29 March 15, 1986 9 1986/87 Mature Pine December 19, 1986 30 January 8, 1987 30 January 26, 1987 30 February 6, 1987 30 February 24, 1987 30 March 3, 1987 30 March 26, 1987 30 Irrmature Pine December 19, 1986 30 January 8, 1987 30 January 26, 1987 30 February 6, 1987 30 February 24, 1987 30 March 3, 1987 30 March 26, 1987 30 Wetland December 19, 1986 30 January 8, 1987 30 January 26, 1987 30 February 6, 1987 30 February 24, 1987 30 March 3, 1987 30 March 26, 1987 30 43.5 51.1 61.8 52.0 62.8 56.5 34.6 .8 .6 41 45 50.8 54.9 55.1 61 .8 60.0 40.8 42.8 48.0 55.4 55.7 55.0 56.6 50.5 57.3 66.7 71 .3 74.3 77.7 72.5 5.3 5.6 11 .5 9.4 4.4 7.4 4.2 3.8 5.4 5.3 6.9 7.6 5.9 7.3 4.1 4.7 5.8 6.6 8.0 13.8 8.1 6.2 4.9 5.8 7.0 6.5 14.1 13.5 41.0-46.0 49.0-53.2 56.4-66.2 47.8-56.2 60.2-65.4 53.7-59.3 31.4-36.8 40.4-43.2 43.6-47.6 48.8-52.8 52.3-57.5 52.3-57.9 59.6-64.0 57.3-62.7 39.3-42.3 41.0- 44.6 43.1- 54.7 52.9-57.9 52.7- 58.7 49.8- 60.2 53.6-59.6 48.2-52.8 55.5-59. 64.5-68 68.7-73, 71.9-76, 72.4-83, 67.4-77.6 137 1987/88 Mature Pine December 18, 1987 30 23.3 2.0 22.6-24.0 January 3, 1988 30 27.2 3.1 26.1-28.3 January 23, 1988 30 32.8 2.4 32.0-33.7 February 2, 1988 30 38.2 2.6 37.3-39.1 February 20, 1988 30 40.1 2.4 39.2-41.0 March 2, 1988 30 38.5 3.4 37.3-39.7 March 20, 1988 30 36.7 2.9 35.7-37.8 Irrmature Pine December 18, 1987 30 21.6 2.9 20.5-22.6 January 3, 1988 30 27.0 2.9 26.0-28.1 January 23, 1988 30 29.9 6.6 27.6-32.2 February 2, 1988 30 36.5 6.3 34.3-38.8 February 20, 1988 30 37.0 3.9 35.6-38.4 March 2, 1988 30 32.5 5.3 30.6-34.5 March 20, 1988 30 33.3 4.6 31.7-35.0 Wetland December 18, 1987 30 29.4 2.5 28.6-30.3 January 3, 1988 30 33.7 3.1 32.6-34.8 January 23, 1988 30 39.7 3.7 38.4-41.1 February 2, 1988 30 49.5 3.1 48.4-50.6 February 20, 1988 30 50.0 3.2 48.9-51.2 March 2, 1988 30 48.6 4.1 47.2-50.1 March 20, 1988 30 47.8 4.5 46.2-49.4 APPENDIX III SUMMARY OF FECAL ANALYSIS DATA 139 Table 1. Percent composition of vegetation types 1n fecal pellet groups determined by fecal fragment analysis from samples collected in the Itcha-Ilgachuz and Tweedsmuir-Entiako study areas. Terres-t r i a l Arboreal Sedge/ Moss/ Date Lichen Lichen Conifer Shrub Forb Grass Rush Clubmoss Itcha/Ilgachuz Feb. 1984 38. 8 35. 1 3. 1 1 . 4 1.7 13. 3 3.3 3. 3 1985 June 3-12 26. 7 24. 1 2. 5 4. 7 9.5 12. 8 6.8 12. 9 July 5 11. 8 13. 8 0. 0 10. 0 11.4 28. 2 12.6 12. 2 July 24 16. 8 17. 9 . 2 14. 8 10.9 22. 6 10.6 6. 2 Oct 20 38. 5 42. 3 4. 4 2. 1 7.2 2. 1 1.5 1 . 9Nov 10 45. 0 30. 7 1. 9 2. 0 .7 5. 2 5.9 8. 6 1986 Jan 20 41 . 7 28. 9 11. 0 4. 4 1.4 3. 9 3.7 5. 0 Feb 21 31 . 9 23. 3 0. 0 7. 9 0.0 11. 4 .4 25. 1 (Alpine) Feb 23 35. 1 33. 2 8. 3 3. 8 1.7 4. 0 3.8 10. 1 March 21 33. 0 14. 9 0. 0 4. 5 2.1 7. 5 0.0 38. 0 (Alpine) March 23 26. 6 34. 3 13. 9 5. 0 1 .8 5. 1 .6 12. 7 June 6 32. 1 14. 7 1 . 5 5. 4 9.3 14. 3 2.8 19. 9 July 6 17. ,3 16. 4 . 8 13. 8 13.9 18. 3 5.4 14. 1 Dec 17 32. 4 40. 9 11 . 7 1 . 9 3.0 2. 5 2.6 5. 0 1987 Jan 9 41 . ,2 7. 2 13. 3 4. 1 4.2 3. 3 4.7 22. 0 Feb 5 34. 6 36. 4 15. 8 3. 3 1 .9 1. 3 2.0 4. 7 March 3 35. ,0 31 . 2 19. 8 3. 5 3.5 2. 0 2.0 3. 0 April 13 33. 8 28. 7 7. 6 2. 7 19.1 3. 1 2.3 2. 7 May 9 42. ,1 28. 0 7. 2 1 . 8 1 .4 6. 4 6.0 7. 1 Dec 16 38. 1 43. 2 • 2 3. 9 1 .8 6. 0 2.7 4. 1 Tweedsmuir-•Entiako 1986 Jan 11 33. ,3 33. 7 14. 0 6. 2 4.1 1 . 6 1 .0 6. 1 Feb 10 32. ,4 32. 0 17. 8 4. 2 3.5 4. 6 2.3 3. 2 March 3 25. ,5 24. 6 17. 7 5. 0 7.4 1. 4 3.1 15. 3 Dec 13 32. ,4 29. 7 14. 4 4. 8 2.6 2. 1 1.1 12. 9 1987 Jan 17 30. ,7 27. ,9 9. 9 4. 7 2.1 2. 9 2.4 19. 4 Feb 16 33. ,7 32. 2 9. 8 6. 3 2.1 1 . 6 .8 13. 5 Feb 25 39, ,5 19. ,9 4. 3 7. 6 3.2 2. 6 1 .7 21 . 2 (Alpine) March 21 29, .5 15. ,8 8. 5 9. 0 8.9 12. 4 6.0 9. 9 Table 2. Mean percent nitrogen values of caribou fecal pellet groups collected in the Itcha-Ilgachuz and Tweedsmuir-Entiako study areas. Itcha/Ilgachuz February 1984 8 1985 Feb 10 March 10 June 3-12 10 July 5 10 July 24 10 October 20 9 November 10 10 1986 January 20 10 February 21 10 (Alpine) February 23 10 March 19 8 (Alpine) March 23 10 December 17 10 1987 January 8-11 6 February 5-8 10 March 3-5 10 April 13 9 May 9 9 June 3-7 10 December 16 10 Tweedsmuir-Ent1ako 1986 January 11 10 February 10 10 March 3 10 1987 January 17-20 10 February 16-19 10 February 25-28 10 (Alpine) March 21-23 10 95% Standard Conf i dence Mean Deviation Interval 1.53 .09 1.46-1.60 1.55 .48 1.22-1.88 1.41 .05 1.38-1.44 1.72 .28 1.52-1.92 2.41 .47 2.08-2.74 2.51 .26 2.33-2.69 1.67 .13 1.58-1.76 1.58 .12 1.49-1.67 1.65 .10 1.58-1.72 1.46 .07 1.41-1.51 1.64 .06 1.59-1.69 1.49 .13 1.38-1.60 1.61 .06 1.57-1.65 1.64 .11 1.56-1.72 1.67 .07 1.59-1.75 1.55 .05 1.52-1.58 1.53 .06 1.49-1.57 1.63 .11 1.54-1.72 1.82 .14 1.71-1.93 1.61 .32 1.38-1.84 1.61 .06 1.57-1.65 1.71 .15 1.60-1.82 1.58 .09 1.51-1.64 1.68 .04 1.65-1.71 1.77 .11 1.69-1.85 1.71 .16 1.60-1.82 1.63 .11 1.52-1.74 1.71 .13 1.62-1.80 APPENDIX IV OVERVIEW OF ECOLOGICAL CHARACTERISTICS OF TERRESTRIAL LICHENS IN RELATION TO WOODLAND CARIBOU 142 On the Tweedsmuir-Ent1ako and Itcha-Ilgachuz winter ranges, Cladina spp., Cladonia spp., Stereocaulon spp. and Peltigera spp. were the most coTrmon and abundant terrestrial lichens (B.C.M.O.F. 1987a, 1987b). Cetrarla spp. were uncommon. Bryoria sp. were the most common arboreal lichens. Holleman and Luick (1977) found that Cladina spp. were the most preferred lichen species, followed by Stereocaulon spp. and Cetraria spp. Peltigera apthosa was consistently avoided. Terrestrial lichen species vary with successional stages as do vascular plants. After disturbance (such as f i r e or logging), crustose lichens are the f i r s t lichens to colonize (3-10 years) followed by fast growing Cladonia spp. in young stands (10 - up to 50 years) and slower growing Cladina spp. in older, mature stands (>40 years) (Aht1 1977, Carroll and Bliss 1982, Johnson 1981, Rowe 1984). Stereocaulon spp. are associated with recurrent f i r e disturbance and grow on very open dry sites (Kershaw 1977) and Peltigera spp. are generally associated with more mesic sites (Ahti 1977). The most preferred lichen species do not become established and abundant in forested areas until up to 50 years after disturbance. In general, lichens are low in protein content; Cladina spp .and Cladonia spp. usually contain less than 3% protein, whereas arboreal lichens (4-7%), Peltigera spp. and Stereocaulon spp. (6.7-8.0%) contain higher levels of protein (Nieminen and Heiskari 1989, Rowe 1984, Scotter 1965). The low protein content of lichens is offset by high d i g e s t i b i l i t y by caribou (Thomas et a l . 1984, Person et a l . 1980a). Although caribou select terrestrial lichens with the lowest nitrogen levels, supplementation of the diet with Peltigera spp., Stereocaulon spp. and evergreen shrubs may be important to maintain caribou condition during winter (Russell and Martell 1984). 143 REFERENCES Ahti, T. 1977. Lichens of the Boreal Coniferous Zone. pp.145-181. In: Seaward, M.R.D. (ed.). Lichen Ecology. Academic Press, London. Brit i s h Columbia Ministry of Forests. 1987a. Winter habitat units of caribou in the Entlako River area, west central B r i t i s h Columbia. Prince Rupert Forest Region, Smithers, B.C. Br i t i s h Columbia Ministry of Forests. 1987b. Caribou habitat units of the Itcha and Ilgachuz areas. Cariboo Forest Region, Williams Lake, B.C. Carroll, S.B. and L.C. Bliss. 1982. Jack pine - lichen woodland on sandy s o i l s in northern Saskatchewan and northeastern Alberta. Can. J. Bot. 60: 2270-2282. Holleman, D.F., and J.R. Luick. 1977. Lichen species preference by reindeer. Can. J. Zool. 55: 1368-69. Johnson, E.A. 1981. Vegetation organization and dynamics of lichen woodland corrmunities in the Northwest Territories, Canada. Ecology 63(1): 200-215. Kershaw, K.A. 1977. Studies on lichen-dominated systems. XX. An examination of some aspects of the northern boreal lichen woodlands 1n Canada. Can. J. Bot. 55: 393-410. Nieminen, M. and U. Heiskari. 1989. Diets of freely grazing and captive reindeer during surrmer and winter. Rangifer 9(1): 17-34. Person, S.J., R.E. Pegau, R.G. White and J.R. Luick. 1980a. In vitro and nylon-bag d i g e s t i b i l i t i e s of reindeer and caribou forages. J. Wildl. Manage. 44(3): 613-622. Rowe, J.S. 1984. Lichen Woodland in northern Canada, pp. 225-237. In: Northern ecology and resource management. Univ. Alta. Press. Edmonton. Russell, D.L. and A.M. Martell. 1984. Winter range ecology of caribou (Rangifer tarandus). pp.117-144 in: Northern ecology and resource management. Univ. Alta. Press. Edmonton. Scotter, G.W. 1965. Chemical composition of forage lichens from northern Saskatchewan as related to use by barren-ground caribou. Can. J. Plant Sci. 45(3):246-250. Thomas, D.C., P.Kroeger and D. Hervleux. 1984. In Vitro digestibi1ities of plants u t i l i z e d by barren-ground caribou. Arctic 37(1):31-36. 

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