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Industrial forestry activities can increase landscape fragmentation, impacting wildlife populations, particularly Canada's woodland caribou, Rangifer tarandus caribou. To protect caribou in areas with forestry activities, the province of Ontario, Canada, implemented a Dynamic Caribou Harvest Schedule (DCHS). The DCHS spatially aggregates harvest disturbance into regions and distributes them across the landscape to maintain forest patch size–age distributions consistent with a natural variation range. However, the DCHS may negatively impact the cost of timber supply. We compared the DCHS with an alternative zoning approach that assigned the harvest deferral and operational management zones within a large forest area. We compared these approaches using an optimization model that combined harvest scheduling, access road construction, and caribou protection sub-problems. We formulated the protection of caribou habitat and road construction as network flow problems, while the harvesting problem incorporated the ecological constraints prescribed by the forest management plan. We compared the DCHS and zoning approaches in the Wabadowgang Noopming Forest of Ontario, a boreal area within the caribou distribution zone. For the same volume of sustainable harvest, the zoning approach protected less total area but more habitat and old-growth stands over the long term, and yielded lower timber costs by 1.2–2.2 $·m−3 than the DCHS. [ABSTRACT FROM AUTHOR]

Post-glacial origins of woodland caribou (Rangifer tarandus subsp.) on the island of Newfoundland and their relationship to mainland populations have been uncertain. Sequence analysis of 2223 bp of the mitochondrial DNA control region and cytochrome b gene from 233 Newfoundland caribou identified 32 haplotypes in four major clades. Comparison with other Nearctic caribou confirms a closer affinity of the basal Clade A with animals from the mainland, and as an outgroup to Clades B, C, and D that are endemic to the island. This indicates re-entry of caribou to post-glacial Newfoundland across the Strait of Belle Isle from Labrador, rather than from southern coastal refugia. Newfoundland caribou are a distinct subspecies, Rangifer tarandus terranovae (Bangs, 1896). Hierarchical AMOVA shows significant clinal differentiation of the major clades from northwest to southeast across the island. The isolated Avalon Peninsula population in the extreme southeast is genetically depauperate. Founder effects are evident in herds introduced to previously unoccupied areas by wildlife managers over the past 40–50 years. Reindeer introduced in the early 20th century have not contributed to mtDNA diversity in Newfoundland caribou. [ABSTRACT FROM AUTHOR]

Environment and Climate Change Canada (ECCC) calculated that 55% of Saskatchewan's Boreal Shield has been disturbed by wildfire in the last 40 years. The 2012 Canadian Federal Recovery Strategy for woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788)) states that these large-scale natural disturbances can cause caribou to cease use of portions of their range. This assumption neglects the potential habitat value of postfire residuals. We tested this assumption using 2 years of GPS data obtained from 56 female caribou to identify calving site selection. Seventy-nine calving events were identified from 91 individual calving seasons. For both calving and postcalving periods, woodland caribou preferred nonburned (>40 years) over burned habitats (≤40 years). Within burned areas, residual patches dominated by bogs-fens were preferred, indicating that burns with residuals are important woodland caribou calving habitat. The residuals may act as island refuges providing food-security, while surrounding burns provide reduced visual obstruction from which caribou can detect approaching predators. Although more data are necessary to make robust conclusions, this study provides novel insight into the ecological interactions of forest fires with woodland caribou in northern Saskatchewan, and offers important considerations regarding critical habitat identification and range-level planning to ensure all suitable caribou habitats are identified. [ABSTRACT FROM AUTHOR]

We present a forest harvest scheduling model that meets timber harvest targets while maximizing a proxy measure of woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788)) habitat based on the configuration of preferred habitat on the landscape. Woodland caribou within the boreal forest region in Canada tend to prefer mature jack pine forest stands, which tend to be rich in their preferred resource, lichen, and also reduce predation pressure. This can create conflict with industrial wood supply needs. We designed a model that can be used to identify good harvest scheduling plans given these competing objectives. Our approach is to use a series of sequential linear programming models that are solved within a replanning framework. Specifically, each individual linear programming model seeks to produce a solution that will meet timber harvest targets while minimizing the harvest of high-quality woodland caribou habitat stands. Stands are assessed with respect to their suitability as woodland caribou habitat based on their contribution to the overall landscape equivalent connected area (ECA), a combined spatial measure of preferred habitat amount and its connectivity. We used our model for a case study of the Trout Lake Forest in northwestern Ontario, Canada, and found that our model creates approximately 10% more caribou habitat than an earlier heuristic procedure and 30% more caribou habitat than the prevailing woodland caribou habitat forest management plan in the Trout Lake Forest while meeting the same timber harvest targets. [ABSTRACT FROM AUTHOR]

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]

Woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788)) populations have declined throughout their range. With the goal of better understanding habitat selection and fidelity during the neonatal calving period (0-4 weeks), we applied a noninvasive method that estimates calving events and subsequent survival based on changes in movement rates among GPS-collared female caribou. We examined a long-term GPS-collar data set (1998-2014) collected from 81 adult female caribou in two central mountain herds in Alberta and British Columbia, Canada. Although we were unable to validate our results with aerial surveys and pregnancy tests, our estimates of parturition rates, survival rates, calving dates, and habitat selection were consistent with previous studies. We identified 83 calving sites. Female caribou selected calving sites and postparturition habitat on high-elevation ridgetops with gradual slopes and avoided anthropogenic linear features. Female caribou displayed low fidelity to interannual calving ranges with a mean distance of 8.7 km between calving ranges. Fidelity was lower in areas with high seismic-line density. Conservation of high-elevation habitat with limited anthropogenic disturbance is likely to provide the greatest benefit to central mountain caribou during the neonatal calving period, and represents a potential management strategy for population recovery efforts. [ABSTRACT FROM AUTHOR]

Generalist predators typically have broad diets, but their diets may become constrained when one species of prey becomes disproportionately available. Yet there is poor understanding regarding whether generalist predators exhibit stereotypic relationships with pulsed prey resources. We used telemetry data from 959 woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788); 146 adult females, 813 calves), 61 coyotes ( Canis latrans Say, 1823), and 55 black bears ( Ursus americanus Pallas, 1780) to investigate how two generalist predators interacted with caribou neonates on the island of Newfoundland. We examined the similarity of patterns of habitat use between caribou and their predators across time and related this similarity to interspecific spatiotemporal co-occurrence and mortality risk for caribou neonates. The similarity in habitat use between coyotes and caribou mirrored variation in juvenile hazard risk, but had weak association with actual co-occurrence with caribou. Bears and caribou exhibited less similarity in habitat use during the calving season than coyotes and caribou. The relationship between habitat use of bear and caribou did not correspond with either co-occurrence patterns or overall risk for caribou neonates. Our work illustrates how risk for a prey species can be shaped differently based upon differences between the behavioural strategies of generalist predator species. [ABSTRACT FROM AUTHOR]

Resource selection functions are useful tools for land-use planning, especially for wide-ranging species with sensitivity to anthropogenic disturbance. We evaluated five a priori hypotheses describing seasonal habitat selection of woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788)) across three regions in northern Ontario. Two regions were Boreal Shield dominated, one area with relatively high anthropogenic disturbance (due to commercial forestry) and the other with relatively low anthropogenic disturbance. The final region was located on the wetland-dominated Hudson Bay Lowlands. Each region encompassed two caribou management ranges: one was used for model development and the other for model evaluation. We developed seasonal resource selection probability functions using seasonal utilization distributions and isopleths derived from GPS collar data (from 212 caribou) to identify high- and low-use areas. We explored selection across five spatial scales; selection patterns were strongest at the 10 000 ha scale. We found temporal and spatial variations in all environmental predictors across ranges and seasons, especially in the Hudson Bay Lowlands. Our results consistently supported the integrated global model (with common variables but range-specific coefficients) where caribou habitat use is related to minimizing apparent competition with moose ( Alces alces (L., 1758)) while avoiding disturbed areas, and utilizing areas with adequate forage. [ABSTRACT FROM AUTHOR]

We used remote video cameras to assess seasonal diet composition of woodland caribou ( Rangifer tarandus tarandus (L., 1758)) at three areas across the boreal forest of Ontario. Caribou consume lichens in winter, but we expected they would significantly reduce lichen consumption in favour of higher protein levels in green plants in summer. We sampled videos from 23 caribou, from 2 years, to derive seasonal diet composition. Diet differed among seasons and study areas, except in winter when lichens dominated. Diet breadth doubled from winter to summer, but overlap between seasons was still >60%. Green plants were less commonly eaten than we expected, only three genera were preferred, and few species constituted more than 2% of the diet. Preferred foods varied by land-cover types. Diet differed between managed and unmanaged landscapes but did not result from use of plant species found in successional habitats. Caribou selected a nonoptimal diet in the snow-free seasons, especially with respect to protein, suggesting factors other than nutrition influenced diet choice, and indicating the possibility of bottom-up limitation on production. [ABSTRACT FROM AUTHOR]

Estimation of demographic trends from vital rates provides a powerful means to estimate population trends in cryptic or difficult to study species such as woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788)). Using such methods, Hervieux et al. (2013; Can. J. Zool. 92(12): 872-882) recently showed 11 of 14 woodland caribou populations in Alberta were declining at ∼8%/year following up to 18 years of monitoring. Harron (2015; Can. J. Zool. 93(2): 149-150) critiques our original study, claiming that negative biases in our demographic monitoring exaggerate our conclusions of widespread caribou declines. Here, we systematically review each of Harron's claims of bias, rejecting each of his claims upon careful review of the mechanisms by which his purported claims would manifest in our population trend estimation. Therefore, we conclude that Harron's scientific critique was superficial and misleading. Delays in conservation actions raised by Harron's critique risk diminishing opportunities to conserve and recover this federally and provincially protected species. [ABSTRACT FROM AUTHOR]

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Across Canada, woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788)) populations are declining because of human-induced changes to food webs that are resulting in apparent competition-induced increases in predator-caused caribou mortality. We tested the hypothesis that wolf ( Canis lupus L., 1758) population reduction could reverse declines in a woodland caribou population following a BACI (before-after-control-impact) design conducted over a 12-year period in west-central Alberta, Canada. We monitored annual survival for 172 adult female caribou and calf recruitment from 2000 through 2012 and conducted a provincial government delivered wolf population reduction program annually during the winters of 2005-2006 to 2012 (inclusive) in an area centered on the Little Smoky range. Wolf removal translated to a 4.6% increase in mean population growth rate of the Little Smoky population mostly through improvements in calf recruitment. In contrast, the Red Rock Prairie Creek control population exhibited a 4.7% decline. Although the wolf population reduction program appeared to stabilize the Little Smoky population, it did not lead to population increase, however, with λ remaining approximately equal to 1. Therefore, we recommend, if required, predation management be combined with effective habitat conservation and long-term planning to effect the recovery of species, such as woodland caribou, which are declining as a result of habitat-mediated apparent competition. [ABSTRACT FROM AUTHOR]

Understanding the factors that drive species distributions is emerging as an important tool in wildlife management, under unprecedented changes in species ranges. While invasion ecologists have long studied the impact of human land use on species' distributions, and models developed more recently to explain changes in species range boundaries have been largely parameterized by climate variables, few authors have considered climate and land-use factors together to explain species distribution. The purpose of this study was to test two main competing hypotheses involving human land use and climate effects on white-tailed deer ( Odocoileus virginianus (Zimmermann, 1780)) distribution, which has expanded into the boreal ecosystem in recent decades. Using a species distribution modeling approach with data from boreal Alberta, we found that climate, as measured by an index of winter severity, was the most important individual factor determining current white-tailed deer distribution in boreal Alberta. Human land use (as measured by total land-use footprint) acted to substantially increase white-tailed deer presence but only in areas with more severe winter conditions. We use our findings to recommend where limiting or reclaiming the industrial footprint may be most beneficial to limiting white-tailed deer distribution. [ABSTRACT FROM AUTHOR]

Nowhere across Canada is the continued persistence of woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788)) more uncertain than in Alberta due to widespread industrial development. A recent Government of Canada critical habitat review determined that habitat conditions within all Alberta boreal ecotype caribou ranges are unlikely or very unlikely to allow for self-sustaining caribou populations. This habitat-based assessment was based only indirectly on empirical population trends. Here, we estimated empirical population trend and growth rate ( λ) for 13 of Alberta's 16 remaining woodland caribou populations (plus one adjacent population from Saskatchewan) from 1994 to 2012 using demographic monitoring of adult female survival and calf recruitment. We captured and radio-collared a total of 1337 adult female caribou in 14 populations and estimated the mean annual adult female survival across all populations as 0.851. We conducted 158 late-winter calf recruitment surveys across the 14 populations classifying 20 872 caribou and estimated mean recruitment of 0.154 calves/cow (i.e., 0.077 female calves/cow). We then combined annual estimates of adult female survival and female calf recruitment within each population in a simple age-structured population model to estimate population trend. Annual population growth rate across caribou populations averaged 0.918, and was significantly declining, λ < 1.0, for 10 of the 14 caribou populations. Our results confirm that woodland caribou are declining rapidly (with a realized decline of approximately 50% every 8 years) across Alberta, and support conclusions from previous habitat-based assessments that the population viability of caribou is currently compromised, supporting development and implementation of recovery actions to reverse trends. [ABSTRACT FROM AUTHOR]

The diet of woodland caribou ( Rangifer tarandus caribou Gmelin, 1788) in the boreal zone of North America is poorly understood. In large part this is because they occur at low densities in environments that are difficult to access. The only method available for identifying food requirements of wildlife has been histological examination of fecal samples, a technique that suffers from a number of serious limitations. Our study used fecal samples from 125 woodland caribou and animal-borne videos to address two questions: (1) How do the new technologies, video cameras and DNA barcoding, compare with conventional diet analyses of fecal pellets? and (2) Can these techniques be used to determine the diet of woodland caribou? Our results show that microhistology estimates provide an inaccurate approximation of diet; <15% correlation with either barcoding or video techniques. Taxonomic resolution of the histology estimates was very low. Taxonomic resolution to species found in fecal samples was good using video (42%) but better using DNA barcoding (94%). DNA barcoding and video technologies provided dietary data that were highly correlated (70%) among major groups of plants, with terrestrial lichens dominating the late winter through early spring diet. The high species resolution of DNA barcoding may be supplemented by information on habitat preference and degree of feeding selectivity obtained by video surveillance. These novel technologies may be important tools for identifying critical habitat requirements and associated conservation strategies needed for elusive wildlife species that are endangered. [ABSTRACT FROM AUTHOR]

Lichens are an important winter food source for woodland caribou (), but quantifying their abundance is difficult. Here, we present an efficient method for assessing lichen biomass at the stand level in boreal forests. We measured lichens occurring in high enough abundance to serve as a winter food source for woodland caribou in 51 boreal forest stands. Samples of each species or genus were collected from each stand and a mean abundance (cover) to biomass ratio was established. The method does not require samples to be collected or weighed, due to this predetermined relationship, and it also accounts for the variation in biomass among lichen species that are equally abundant. The variation in lichen growth between stands was assessed by means of five lichen abundance classes. The proposed method was tested in 34 stands with a wide range of ages and stem densities. The average time to complete a lichen biomass assessment was approximately 2 h. This method is an efficient and accurate tool that can assist forest managers and researchers with ecological studies on lichens or with monitoring changes in lichen biomass over time and with habitat assessments for organisms for which lichens are important, such as woodland caribou. [ABSTRACT FROM AUTHOR]

Populations of woodland caribou ( (Gmelin, 1788)) have declined across much of their range. Wolves ( L., 1758) are believed to be responsible for the majority of mortality in adult female caribou; however, we hypothesize that other predators such as black bears ( Pallas, 1780) may be important contributors to calf mortality. We assessed habitat selection by black bears and spatial relationships of caribou - black bears during the caribou calving season in northeastern Alberta, Canada. Black bears avoided bogs and fens, while selecting upland mixed woods and various industrial features. Conversely, caribou showed strong selection for bogs and fens relative to bears, supporting the hypothesis that caribou in the boreal forest attempt to minimize predation risk by selecting peatlands to avoid areas frequented by predators. However, habitat selection by individual black bears was highly variable and some bears selected habitats similar to those selected by caribou, i.e., bogs and fens. Bears that specialize on foraging in peatlands might be responsible for some of the predation on caribou calves. Because declines in caribou populations have resulted from a combination of high adult female and calf mortalities, management actions to conserve woodland caribou should consider the entire suite of potential predators rather than focusing only on wolves. [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]

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. La planification de la conservation des espèces préoccupantes ou importantes peut bénéficier de l’utilisation des fonction de sélection des ressources (RSF) qui identifient les sites et les caractéristiques d’intérêt. Les modèles qui se prêtent à des interprétations biologiques et qui possèdent une capacité raisonnable de prédiction peuvent idéalement se baser sur des données provenant d’individus regroupés en fonction de stratégies de sélection saisonnières dans des zones géographiques particulières ou des similarités d’associations topographiques ou végétales. Nous utilisons des régressions logistiques, une méthodologie basée sur la théorie de l’information, de l’imagerie satellitaire et des données de positionnement (n = 31 femelles; 16 803 relevés géographiques) de caribous des bois ((Rangifer tarandus caribou (Gmelin, 1788)) munis de colliers GPS (système de positionnement mondial) afin de modéliser la sélection des ressources par ces animaux durant les saisons de mise bas, d’été, d’automne, de reproduction, d’hiver et de fin d’hiver. Une variation plus élevée dans l’utilisation des ressources correspond aux périodes où les caribous et leurs petits sont le plus vulnérables à la prédation ou lorsque leurs ressources alimentaires sont limitées. Même avec des stratégies multiples de sélection, les caribous se déplacent en général progressivement des habitats de plus haute altitude vers ceux de plus basse altitude après la mise bas, en été et à l’automne. Les caribous font une sélection négative des habitats de la catégorie brûlés-perturbés ou les évitent entièrement en toute saison, sauf en été. Nous avons incorporé les RSF dans un système d’information géographique en trames afin de créer des paysages de sélection. Nous avons validé les paysages de sélection à l’aide de données GPS retenues (n = 6077), de 50 sites connus de mise bas et du coefficient de corrélation de rang de Spearman. Les modèles de sélection et les paysages de sélection finaux fonctionnement bien pour la validation du positionnement de l’utilisation des caribous en toute saison (tous les P < 0,003) et la prédiction des sites connus de mise bas (P < 0,001). Lorsque les stratégies saisonnières de sélection sont connues et que les modèles sont couplés à une validation, les RSF sont des outils efficaces pour aider à la planification de la conservation. [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]

Woodland caribou (Rangifer tarandus caribou (Gmelin)) populations are in decline throughout much of their range. With increasingly rapid industrial, recreational, residential, and agricultural development of caribou habitat, tools are required to make clear, knowledgeable, and explainable management decisions to support effective conservation of caribou and their range. We developed a series of Bayesian belief networks to evaluate conservation policy scenarios applied to caribou seasonal range recovery areas. We demonstrate the utility of the networks to articulate ecological understanding among stakeholders, to clarify and explicitly depict threats to seasonal range. We also show how simulated forecasts of spatially explicit seasonal range can be compared with landscape potential with range under assumed conditions of natural disturbance. These tools have provided opportunities to operationally define and measure conditions for recovery of caribou in north-central British Columbia. [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]

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. [ABSTRACT FROM AUTHOR]

Examines the habitat selection and demography of woodland carbou population in Newfoundland. Effect of interaction among human-induced habitat selection; Impact of black bear predation; Pregnancy and recruitment rates; Potential causes of mortality.

Linear developments such as roads, seismic lines, and pipeline rights-of-way are common anthropogenic features in the boreal forest of Alberta. These features may act as barriers to the movement of threatened woodland caribou, Rangifer tarandus caribou. Seismic lines were not barriers to caribou movements, whereas roads with moderate vehicle traffic acted as semipermeable barriers to caribou movements. Twenty-two adult female and 1 adult male woodland caribou were captured and collared on February 17–19, 1998. Each caribou was fitted with a global positioning system collar. The greatest barrier effects were evident during late winter, when caribou crossed actual roads 6 times less frequently than simulated road networks. Semipermeable barrier effects may exacerbate functional habitat loss demonstrated through avoidance behavior. Caribou may cross roads less frequently than expected for a number of reasons, including an aversion to the physical barrier presented by a road and associated forest opening, vehicle traffic, or predation by humans. The effects of habitat fragmentation through habitat loss, avoidance, and the semipermeable barrier effects of roads should be considered in developing strategies to maintain woodland caribou populations in Alberta. Roads that act as semipermeable barriers to caribou movements may make the presence of caribou more predictable in space and time, and hence compromise the "spacing out" strategy that caribou adopt to reduce predation. The approach we have outlined in this paper is a useful method to quantify the effects of human developments acting as semipermeable barriers to animal movements and should be considered in the development of animal-movement models.

We employed satellite-telemetry data to examine seasonal movement rates, annual- and seasonal-range sizes, and season-to-season range fidelity of female woodland caribou (Rangifer tarandus caribou) from five populations in the boreal forest of Saskatchewan. The populations studied are limited by predation, and we investigated whether female caribou exhibited movement and range use consistent with predator avoidance. Additionally, we document an animal-centred technique for assessing site fidelity on the basis of individual range use throughout a year. Females accompanied by calves had lower movement rates and smaller seasonal ranges than females without calves. Movement rates among female caribou tended to decline between the rut and the postcalving and summer seasons. Trends indicated that seasonal ranges were larger prior to calving than during the postcalving and summer seasons. We interpreted the range sizes and movement rates observed as being consistent with predator avoidance in nonmigratory caribou populations. Despite these results and high rates of calf mortality in the area, we did not find interannual fidelity to calving sites.Nous nous sommes servis de données de télémétrie par satellite pour étudier les taux des déplacements saisonniers, la taille des domaines annuels et saisonniers et la fidélité à un domaine chez des femelles du Caribou des bois (Rangifer tarandus caribou) de cinq populations dans la forêt boréale de la Saskatchewan. Les populations étudiées sont limitées par la prédation et nous avons examiné si les déplacements et les domaines des femelles peuvent être reliés à leur évitement des prédateurs. De plus, nous décrivons une technique centrée sur les animaux pour évaluer leur fidélité à un site d'après l'utilisation de leur domaine pendant toute l'année. Les femelles accompagnées de petits ont des taux de déplacement plus faibles et leurs domaines saisonniers sont plus petits que ceux des femelles sans petits. Les taux de déplacement chez les femelles ont tendance à décliner entre le rut et la période qui suit la mise bas et durant l'été. Les tendances indiquent que les domaines saisonniers sont plus grands avant la mise bas que durant la période qui suit et durant l'été. Nous interprétons les dimensions des domaines et les taux de déplacement observés comme des stratégies d'évitement des prédateurs chez les populations non migratrices de caribous. Malgré ces résultats et malgré les taux de mortalité élevés des petits dans la région, nous n'avons pas constaté de fidélité aux sites de mise bas d'une année à l'autre.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Some researchers have suggested that over periods of several decades, Arctic tundra caribou (Rangifer tarandus) may be regulated by density-dependent forage depletion. Winter range shifts could potentially delay such regulation when a population is at or near long-term maximum abundance. In the 1980s, Inuit correctly predicted the mass emigration of caribou from a traditional winter range on Foxe Peninsula (FP) on southern Baffin Island, Nunavut, Canada. Most FP caribou subsequently emigrated to a new winter range on Meta Incognita Peninsula (MIP). To determine if MIP provided emigrating caribou with better foraging habitats, we compared winter forage resources and snow cover at caribou foraging sites, and food selection by caribou on FP and MIP in April 1992. Caribou that remained on FP dug feeding craters in shallower, softer snow than those on MIP did. Biomass of most fruticose lichens was greater within foraging sites on MIP than on FP. Biomass of shrubs, other than Cassiope tetragona and Dryas integrifolia, was also greater on MIP than on FP. Dryas integrifolia was the only plant class that had higher biomass on FP than on MIP.Cladina spp. / Cladonia spp., Sphaerophorus fragilis, and Cetraria nivalis occurred less frequently in the rumens of FP caribou. Proportions of fruticose lichens in rumens of caribou on both peninsulas were similar to those on other overgrazed and High Arctic tundra winter ranges. Caribou on FP showed a higher preference for the shrub C. tetragona. Biomasses of plants sensitive to long-term feeding or trampling by caribou (i.e., the five most common fruticose lichens, other shrubs, and plant debris) were consistently lower on FP, which is congruous with Inuit reports that long-term cumulative overgrazing had reduced the supply of important forage plants on FP sites that were accessible to caribou in winter. FP caribou that emigrated to MIP gained access to more abundant, higher quality forage resources than those that remained on FP. Because most FP caribou had emigrated, this South Baffin subpopulation escaped, at least temporarily, the regulating effects of historical cumulative overgrazing.Des chercheurs croient que, sur une période de plusieurs décennies, les populations de caribous de la toundra arctique (Rangifer tarandus) peuvent être contrôlées par un épuisement du brout dépendant de la densité. Des changements d'aires d'hiver peuvent retarder ce contrôle quand une population a atteint ou est près d'atteindre son abondance maximale à long terme. Au cours des années 1980, les Inuits avaient prédit l'émigration en masse des caribous de leur aire traditionnelle d'hiver dans la péninsule Foxe (FP), dans le sud de la terre de Baffin, Nunavut, Canada. La plupart des caribous FP ont émigré vers une nouvelle aire d'hiver dans la péninsule de Meta Incognita (MIP). Dans le but de déterminer si la nouvelle aire contenait de meilleurs habitats pour l'alimentation des caribous émigrés, nous avons comparé les ressources de brout d'hiver, la couche de neige aux sites d'alimentation et le choix des aliments chez les caribous FP et MIP en avril 1992. Les caribous qui sont restés dans la FP se creusaient des trous d'alimentation moins profonds, dans de la neige plus molle, que les caribous MIP. La biomasse des lichens fruticuleux était plus élevée aux sites d'alimentation de la MIP que de la FP. La biomasse des buissons autres que Cassiope tetragona et Dryas integrifolia était aussi plus élevée dans la MIP que dans la FP. Dryas integrifolia s'est avérée la seule classe de plantes à avoir une biomasse plus grande dans la FP que dans la MIP.Cladina spp. / Cladonia spp., Sphaerophorus fragilis, et Cetraria nivalis ont été trouvés moins fréquemment dans les rumens des caribous FP. La proportion de lichens fruticuleux dans les rumens des caribous des deux péninsules était semblable à celle qu'on retrouve ailleurs dans les aires d'hiver des caribous de la toundra du haut Arctique qui sont broutées à l'excès. Les caribous FP ont montré une préférence plus grande pour la plante buissonneuse C. tetragona que les caribous MIP. La biomasse des plantes peu résistantes au broutage et au piétinement à long terme des caribous (i.e., les cinq lichens fruticuleux les plus communs, autres buissons et débris de plantes) était toujours moins élevée dans la FP, ce qui corrobore les dires des Inuits à l'effet que le broutage excessif cumulatif a réduit substantiellement la quantité de plantes importantes broutées par les caribous en hiver dans la FP. Les caribous FP qui ont émigré dans la MIP ont acquis l'accès à un brout plus abondant et de meilleure qualité que celui de la FP. Comme la plupart des caribous FP ont émigré, cette population de caribous du sud de la Terre de Baffin a échappé, du moins temporairement, aux effets cumulatifs du broutage excessif qui assurent habituellement le contrôle de cette population.[Traduit par la Rédaction] [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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