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High-quality habitats for caribou ( Rangifer tarandus (L., 1758)) are associated primarily with lichens, but lichens alone fail to satisfy summer nutritional requirements. To evaluate the summer forage value of plant communities across northeastern British Columbia (BC), where populations of northern and boreal ecotypes of caribou are declining, we observed foraging by tame, female caribou. We compared diet composition with forage abundance to determine forage selection and to quantify forage availability. Deciduous shrubs, not lichens, largely dominated summer diets. Caribou were highly selective foragers, with 28 species comprising 78% of diets. Caribou avoided ≥50% of understory vegetation in all communities, especially conifers, evergreen shrubs, mosses, and two genera of terrestrial lichens. Availability of accepted forage (species not avoided) was strongly heterogeneous across landscapes. Alpine shrub areas and mid-elevation spruce-fir stands in the mountains, as well as treed rich fens and white spruce communities in the boreal forests, provided the greatest quantities of accepted forage for caribou. Dry alpine sites and unproductive black spruce communities provided the least accepted forage. Our work has direct implications to caribou conservation by contributing to a greater understanding of the forage value of summer habitats, with implications to habitat selection, seasonal movements, and distribution ecology. [ABSTRACT FROM AUTHOR]

We investigated whether woodland caribou (Rangifer tarandus caribou) would remain in a 2772 km2 area in eastern Quebec where the forest management plan included the preservation of large forest blocks (35–182 km2) linked with >400 m wide corridors and where cuts were amalgamated in large zones. To evaluate changes in caribou abundance and habitat selection, we conducted five aerial surveys and followed by telemetry 13 to 22 female caribou each year, from March 1998 to March 2005. Caribou numbers declined by 59% between 1999 and 2001 but gradually recovered to initial abundance. Female survival increased from 73.3% in 1999 to 87.3%–93.4% in 2004 and 2005. Caribou selected protected blocks, used corridors in proportion to their availability, and avoided logged areas. They preferred closed conifer stands without terrestrial lichens and open conifer stands with or without terrestrial lichens throughout the study. Open habitats (clearcuts and burns), regenerating sites, mixed and deciduous stands, and water bodies were avoided. The main zones used by caribou gradually shifted towards the southwest of the study area, likely as a result of disturbance and habitat loss due to logging of mature conifers in the east. We conclude that caribou numbers were maintained within the managed area as a result of the presence of protected blocks and uncut continuous forest. [ABSTRACT FROM AUTHOR]

Mountain caribou, an endangered ecotype of woodland caribou (Rangifer tarandus caribou Gmelin, 1788), live in late-successional coniferous forests where they depend largely on arboreal lichens as winter forage. While radio-telemetry has been used to understand caribou habitat selection patterns at broad scales among and within populations, here we use snow-trailing in old cedar–hemlock forests between 1992 and 2003 to study three finer scales of habitat selection: (1) forest stands used for foraging from available forest stands (among-stand selection), (2) foraging paths within selected stands relative to random paths within those same stands (within-stand selection), and (3) feeding items along foraging paths. Relative to stands that were available on the landscape, caribou selected stands with more windthrown trees and standing snags. Within stands, caribou selected paths that had more live trees, snags with branches and bark, and trees with larger diameters. All of these habitat attributes facilitate access to arboreal lichen. Of the potential forage items encountered along foraging paths, caribou preferred to feed on windthrown trees, lichen litterfall and falsebox (Paxistima myrsinites (Pursh.) Raf.). Our results go beyond telemetry studies by revealing that not all old forests are of equal value to mountain caribou. Prioritization among old stands will help refine conservation measures, as will silvicultural systems that incorporate key habitat attributes to maintain winter habitat in low-elevation cedar–hemlock ecosystems. [ABSTRACT FROM AUTHOR]

Quantitative knowledge of the abundance of epiphytic alectorioid lichens (Bryoria spp., Alectoria spp., and Usnea spp.) is important when evaluating the carrying capacity of the winter pastures of semidomesticated reindeer (Rangifer tarandus tarandus (L., 1758)) and woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)). This study, including a total of 234 sample plots, presents data on the biomass of alectorioid lichens in mature forests for the most common forest site types in the national parks of Oulanka, Pallas-Ounastunturi, and Lemmenjoki in northern Finland and relates them to forest stand characteristics. The biomass of alectorioid lichens on trees was estimated using the clump method in which the existing clumps of lichen thalli on branches are compared with clumps of lichens of known dry mass. Estimated biomasses were corrected by equations describing the ratio of estimated to measured biomass. We found the highest mean lichen biomasses (120 kg·ha–1) in subdry, Scotch pine (Pinus sylvestris L.) dominated sites above the timberline of Norway spruce (Picea abies (L.) Karst.). Below that timberline, the highest lichen biomasses were found in fresh (productive) sites dominated by Norway spruce. There the site-specific differences were mainly associated with tree species composition. Though in many previous studies forest age has been an important indicator of total lichen biomass, in our study areas lichen abundance was most commonly correlated with total volume of forest stands. The correlation of biomass with forest volume suggests that substrate availability was the most important limiting factor for alectorioid lichens in our study area. However, it is premature to say whether that is a common feature in northern forests over larger geographic areas. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Wood bison (Bison bison athabascae Rhoads, 1898) were reintroduced to the Aishihik Lake area in the southwestern Yukon, where a population of woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) existed. These species co-occurred in nearby Beringia over several hundred thousand years and in the study area throughout most of the Holocene. We hypothesized that resource-selection patterns should differ widely between species at all scales because co-evolution should have resulted in strong patterns of resource partitioning. We compared winter utilization distributions of both species based on aerial survey data and assessed differential resource selection at the scales of landscape and distributional overlap. We also assessed differential resource use within feeding sites and compared late-winter diets of the two species. We found 41% overlap in 95% utilization distributions but only 6% overlap in 50% utilization distributions. Strong differences were measured for use of space and terrain, including elevation, slope, and distance from permanent water bodies. Bison strongly selected for or used graminoids, while caribou selected for or used lichens at each scale. Overlap in winter diet between the two species was 10%. At current densities, exploitative competition in winter between these species is unlikely. [ABSTRACT FROM AUTHOR]

Managing predators to restore threatened or endangered species is often controversial. Hervieux et al. (2014; Can. J. Zool. 92(12): 1029-1037) report on the efficacy of wolf ( Canis lupus L., 1758) reduction as a recovery strategy in the Little Smoky population of boreal woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788)) range in Alberta, which generated a lot of media attention. As such, the authors were invited by the journal editor who handled the original paper to write this addendum to provide clarification regarding the methodology used in the original paper. Wolf reduction was conducted by Government personnel in accordance with appropriate policy and laws (i.e., federal and provincial Species at Risk Acts; Alberta Wildlife Act; Alberta Woodland Caribou Policy). University-based researchers were involved only in data analysis and writing, and thus did not require approval by a university-based animal welfare board. Collaboration between independent university-based scientists and government biologists is essential to effective assessment of such controversial management practices. Hervieux et al. (2014; Can. J. Zool. 92(12): 1029-1037) in fact concluded that such wolf reductions, by themselves, would only 'buy time' and would not restore woodland caribou alone without effective habitat protection. [ABSTRACT FROM AUTHOR]

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