Comparison of seasonal habitat selection between threatened woodland caribou ecotypes in central British Columbia

Woodland caribou (Rangifer tarandus caribou) in British Columbia have been classified into ecotypes based on differences in use of habitat in winter. Although recovery planning focuses on ecotypes, habitat use and selection varies within ecotypes. Our objectives were to compare habitat use and selection among previously identified woodland caribou herds at the transition zone between northern (Moberly, Quintette, and Kennedy herds) and mountain (Parsnip herd) ecotypes in central British Columbia. We developed selection models for each herd in spring, calving, summer/fall, early and late winter. Topographic models best predicted selection by most herds in most seasons, but importance of vegetation-cover was highlighted by disproportionate use of specific vegetation-cover types by all caribou herds (e.g., in early winter, 75% of Kennedy locations were in pine-leading stands, 84% of Parsnip locations were in fir and fir-leading stands, and 87 and 96% of locations were in alpine for the Moberly and Quintette herds, respectively). Using a combination of GPS and VHF radio-collar locations, we documented some spatial overlap among herds within the year, but use of vegetation-cover types and selection of elevations, aspects, and vegetation-cover types differed among herds and within ecotypes in all seasons. Habitat use and selection were most similar between the two northern-ecotype herds residing on the eastern side of the Rocky Mountains. This research indicates that habitat use and selection by caribou herds in all seasons is more variable than ecotype classifications suggest and demonstrates the value of undertaking herd-specific mapping of critical habitat for woodland caribou.

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Early-winter diet of woodland caribou in relation to snow accumulation, Selkirk Mountains, British Columbia, Canada

Canadian Journal of Zoology ◽

10.1139/z90-372 ◽

1990 ◽

Vol 68 (12) ◽

pp. 2691-2694 ◽

Cited By ~ 20

Author(s):

Eric M. Rominger ◽

John L. Oldemeyer

Keyword(s):

British Columbia ◽

Rangifer Tarandus ◽

Transition Period ◽

Management Strategies ◽

Snow Accumulation ◽

Late Winter ◽

Early Winter ◽

Accumulation Rates ◽

Woodland Caribou ◽

Selkirk Mountains

Woodland caribou (Rangifer tarandus caribou) in the southern Selkirk Mountains of British Columbia shift from a diet of primarily vascular taxa during snow-free months to an arboreal lichen – conifer diet during late winter. We present evidence that caribou diets, during the early-winter transition period, are influenced by snow accumulation rates. Caribou shift to an arboreal lichen – conifer diet earlier during winters of rapid snow accumulation and forage extensively on myrtle boxwood (Pachistima myrsinites), an evergreen shrub, and other vascular plants during years of slower snow accumulation. The role of coniferous forage in early-winter food habits is examined. Forest management strategies can be developed to provide habitat that will enable caribou to forage in response to varying snow accumulation rates.

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Factors influencing variation in site fidelity of woodland caribou (Rangifer tarandus caribou) in southeastern British Columbia

10.26686/wgtn.12971867.v1 ◽

2020 ◽

Author(s):

Heiko Wittmer ◽

B McLellan ◽

F Hovey

Keyword(s):

British Columbia ◽

Site Fidelity ◽

Rangifer Tarandus ◽

Snow Accumulation ◽

Limiting Factors ◽

Late Winter ◽

Behavioural Plasticity ◽

Rangifer Tarandus Caribou ◽

Early Winter ◽

Woodland Caribou

Where predation is a major limiting factor, it has been postulated that woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) reduce movements to minimize contact with predators and exhibit fidelity to seasonal ranges. We examined fidelity behaviour within season and among years of woodland caribou based on locations of 65 radio-collared individuals in British Columbia, Canada. We used average linear distances between all possible pairs of radiolocations of individuals to assess fidelity. Among-year interlocation distances were similar to within-season interlocation distances during summer, indicating that caribou did not shift their distribution during seasons when they were most vulnerable to predation. Among-year interlocation distances were significantly greater than within-season interlocation distances during both early winter and late winter, indicating that individual caribou shifted their distribution among winters. The amount that an individual's distribution shifted among winters varied among and within individuals over different years. During early winter this behavioural plasticity was correlated with snow accumulation, with individuals having greater interlocation distances in years with high snow accumulation. Our results indicate that site fidelity outside the calving season is unlikely solely influenced by predator avoidance. We suggest that seasonal shifts in the importance of limiting factors vary from predation in summer to food in winter. © 2006 NRC.

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Factors influencing variation in site fidelity of woodland caribou (Rangifer tarandus caribou) in southeastern British Columbia

Canadian Journal of Zoology ◽

10.1139/z06-026 ◽

2006 ◽

Vol 84 (4) ◽

pp. 537-545 ◽

Cited By ~ 33

Author(s):

Heiko U. Wittmer ◽

Bruce N. McLellan ◽

Frederick W. Hovey

Keyword(s):

British Columbia ◽

Site Fidelity ◽

Rangifer Tarandus ◽

Snow Accumulation ◽

Limiting Factors ◽

Late Winter ◽

Behavioural Plasticity ◽

Rangifer Tarandus Caribou ◽

Early Winter ◽

Woodland Caribou

Where predation is a major limiting factor, it has been postulated that woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788)) reduce movements to minimize contact with predators and exhibit fidelity to seasonal ranges. We examined fidelity behaviour within season and among years of woodland caribou based on locations of 65 radio-collared individuals in British Columbia, Canada. We used average linear distances between all possible pairs of radiolocations of individuals to assess fidelity. Among-year interlocation distances were similar to within-season interlocation distances during summer, indicating that caribou did not shift their distribution during seasons when they were most vulnerable to predation. Among-year interlocation distances were significantly greater than within-season interlocation distances during both early winter and late winter, indicating that individual caribou shifted their distribution among winters. The amount that an individual’s distribution shifted among winters varied among and within individuals over different years. During early winter this behavioural plasticity was correlated with snow accumulation, with individuals having greater interlocation distances in years with high snow accumulation. Our results indicate that site fidelity outside the calving season is unlikely solely influenced by predator avoidance. We suggest that seasonal shifts in the importance of limiting factors vary from predation in summer to food in winter.

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Factors influencing variation in site fidelity of woodland caribou (Rangifer tarandus caribou) in southeastern British Columbia

10.26686/wgtn.12971867 ◽

2020 ◽

Author(s):

Heiko Wittmer ◽

B McLellan ◽

F Hovey

Keyword(s):

British Columbia ◽

Site Fidelity ◽

Rangifer Tarandus ◽

Snow Accumulation ◽

Limiting Factors ◽

Late Winter ◽

Behavioural Plasticity ◽

Rangifer Tarandus Caribou ◽

Early Winter ◽

Woodland Caribou

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Habitat use by woodland caribou near Takla Lake in central British Columbia

Canadian Journal of Zoology ◽

10.1139/cjz-78-9-1552 ◽

2000 ◽

Vol 78 (9) ◽

pp. 1552-1561 ◽

Cited By ~ 13

Author(s):

Kim G. Poole ◽

Douglas C. Heard ◽

Garth Mowat

Keyword(s):

British Columbia ◽

Habitat Use ◽

Woodland Caribou

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Variation in the seasonal selection of resources by woodland caribou in northern British Columbia

Canadian Journal of Zoology ◽

10.1139/z08-047 ◽

2008 ◽

Vol 86 (8) ◽

pp. 812-825 ◽

Cited By ~ 16

Author(s):

D. D. Gustine ◽

K. L. Parker

Keyword(s):

Conservation Planning ◽

Resource Selection ◽

Rangifer Tarandus ◽

Rank Correlation ◽

Late Winter ◽

Theoretic Approach ◽

Woodland Caribou ◽

Predictive Capacity ◽

Spearman’S Rank Correlation ◽

Selection Strategies

Conservation planning for species of concern or importance can be aided by resource selection functions (RSFs) that identify important areas or attributes. Models that can be interpreted biologically and provide reasonable predictive capacity may best be based on data from individuals grouped into seasonal selection strategies for particular geographical areas or similarities in topographical and vegetative associations. We used logistic regression, the information–theoretic approach, satellite imagery, and locational data (n = 31 females; 16 803 locations) from global positioning system (GPS) collared woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788)) to model resource selection by animals during calving, summer, fall, breeding, winter, and late-winter seasons. Higher variation in resource use corresponded to times when caribou and their young were most susceptible to predation or when food resources were limited. Even with multiple selection strategies, caribou followed a general progression from higher to lower elevation habitats from calving and summer to late winter. Caribou selected against or completely avoided the burned–disturbed vegetation class in every season except summer. We incorporated RSFs with a raster geographic information system to create selection landscapes. We validated selection landscapes using withheld GPS data (n = 6077), 50 known calving sites, and Spearman’s rank correlation coefficient. Selection models and final selection landscapes performed well in validating use locations of woodland caribou in all seasons (all P < 0.003) and in predicting known calving sites (P < 0.001). When seasonal selection strategies are identified and models are coupled with validation, RSFs are effective tools to assist in conservation planning.

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Early Winter Habitat Use by Mountain Caribou in the North Cariboo and Columbia Mountains, British Columbia

Rangifer ◽

10.7557/2.16.4.1229 ◽

1996 ◽

Vol 16 (4) ◽

pp. 133 ◽

Cited By ~ 1

Author(s):

E. Terry ◽

B. McLellan ◽

G. Watts ◽

J. Flaa

Keyword(s):

British Columbia ◽

Habitat Use ◽

Regional Differences ◽

Rangifer Tarandus ◽

Winter Habitat ◽

Use Patterns ◽

The North ◽

Columbia Mountains ◽

Management Plans ◽

Spruce Stands

Winter habitat use was compared between two mountain caribou (Rangifer tarandus caribou) populations in British Columbia. Regional differences were apparent during November and December. Radio-collared caribou inhabiting the gentle plateaus of the northern Cariboo Mountains, near Prince George, B.C. primarily used mid-elevation balsam-spruce stands on moderate slopes (<30%). In contrast, radio-collared caribou in the North Columbia Mountains, near Revelstoke, B.C. used low elevation hemlock-cedar stands and relatively steeper slopes (>30%). To adequately address habitat requirements of caribou, forest management plans should incorporate varying regional and seasonal habitat use patterns. Hypotheses on observed differences in habitat use are discussed.

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Feeding site selection by woodland caribou in north-central British Columbia

Rangifer ◽

10.7557/2.20.5.1642 ◽

2000 ◽

Vol 20 (5) ◽

pp. 158 ◽

Cited By ~ 4

Author(s):

Chris J. Johnson ◽

Katherine L. Parker ◽

Douglas C. Heard

Keyword(s):

British Columbia ◽

Rangifer Tarandus ◽

Lower Percentage ◽

Percent Cover ◽

Woodland Caribou ◽

North Central ◽

Feeding Site ◽

Feeding Sites ◽

Cladina Rangiferina ◽

The Individual

We examined the foraging habits of the northern woodland caribou ecotype {Rangifer tarandus caribou) at the scale of the individual feeding site. Field data were collected in north-central British Columbia over two winters (Dec 1996-Apr 1998). We trailed caribou and measured vegetation characteristics (species composition and percent cover), snow conditions (depth, density, and hardness), and canopy closure at terrestrial and arboreal feeding sites, and at random sites where feeding had not occurred. Logistic regression was used to determine the attributes of feeding sites that were important to predicting fine scale habitat selection in forested and alpine areas. In the forest, caribou selected feeding sites that had a greater percent cover of Cladina mitis and Cladonia spp, lower snow depths, and a lower percentage of debris and moss. Biomass of Bryoria spp. at the 1-2 m stratum above the snow significantly contributed to predicting what trees caribou chose as arboreal feeding sites. In the alpine, caribou selected feeding sites with a greater percent cover of Cladina mitis, Cladina rangiferina, Cetraria cucullata, Cetraria nivalis, Thamnolia spp., and Stereocaulon alpinum as well as lower snow depths.

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Population dynamics of the endangered mountain ecotype of woodland caribou (Rangifer tarandus caribou) in British Columbia, Canada

10.26686/wgtn.12971858.v1 ◽

2020 ◽

Author(s):

Heiko Wittmer ◽

BN McLellan ◽

DR Seip ◽

JA Young ◽

TA Kinley ◽

...

Keyword(s):

British Columbia ◽

Population Dynamics ◽

Rangifer Tarandus ◽

Population Decline ◽

Survival Rates ◽

Adult Survival ◽

Rangifer Tarandus Caribou ◽

Vital Rates ◽

Woodland Caribou ◽

Annual Survival

We used census results and radiotelemetry locations of >380 collared individuals sampled over the entire distribution of the endangered mountain ecotype of woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) in British Columbia, Canada, to delineate population structure and document the size and trend of the identified populations. We also describe the spatial pattern of decline and the causes and timing of adult mortality and provide estimates of vital rates necessary to develop a population viability analysis. Our results indicate that the abundance of mountain caribou in British Columbia is declining. We found adult female annual survival rates below annual survival rates commonly reported for large ungulates. The major proximate cause of population decline appears to be predation on adult caribou. Spatial patterns of population dynamics revealed a continuous range contraction and an increasing fragmentation of mountain caribou into smaller, isolated subpopulations. The population fragmentation process predominantly occurs at the outer boundaries of the current distribution. Our results indicate that recovery strategies for mountain caribou should be directed at factors contributing to the fragmentation and isolation of mountain caribou populations as well as management strategies aimed at increasing adult survival. © 2005 NRC Canada.

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Translocation and Recovery Efforts for the Telkwa Caribou, Rangifer tarandus caribou, Herd in Westcentral British Columbia, 1997-2005

The Canadian Field-Naturalist ◽

10.22621/cfn.v121i2.440 ◽

2007 ◽

Vol 121 (2) ◽

pp. 155 ◽

Cited By ~ 6

Author(s):

Astrid Vik Stronen ◽

Paul Paquet ◽

Stephen Herrero ◽

Seán Sharpe ◽

Nigel Waters

Keyword(s):

British Columbia ◽

Habitat Use ◽

Rangifer Tarandus ◽

Initial Study ◽

High Elevation ◽

Rangifer Tarandus Caribou ◽

Habitat Features ◽

Lower Elevation ◽

Significant Difference ◽

High Elevations

During 1997–1999, 32 Woodland Caribou (Rangifer tarandus caribou) were translocated from the Sustut Herd to the Telkwa Mountains in westcentral British Columbia to augment recovery of the Telkwa Caribou Herd. The animals were fitted with radiocollars and located during 1997–2000 to determine selection of habitat features and terrain variables. Six Caribou calves were also collared to determine causes and timing of calf mortality during summer 1999. Defining available habitat for newly translocated animals is often arbitrary and subjective, and we based the analyses on ranks for habitat use and availability as this is less sensitive to the inclusion or exclusion of a questionable resource. This method represents some loss of information but provides indications of the relative importance of various habitat types without classifying any as avoided. High elevation habitat (> 1700 masl) on moderate slopes (16 – 45°) received the highest ranks, as did “warm” (136 – 315°) aspects and forests > 250 years old. Three calves died shortly after birth. One calf appeared to have been killed by predation, likely by a Golden Eagle (Aquila chrysaetos), and one calf was abandoned by the cow. Cause of death for the third calf is unknown. To assess habitat use associated with calving we compared summer locations with data obtained throughout the rest of 1999 for eight cows with calves and eight without calves. We found significant difference in use of elevation during calving time, when cows with calves remained at high elevations and barren cows generally descended to lower elevation habitat. Surveys conducted in 2005, five years after the completion of the initial study, produced a count of approximately 90 Caribou. This suggests that in the short term, the translocation was successful in re-establishing a self-sustaining Caribou population in the Telkwa Mountains.

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