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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]

The Canadian boreal forest biome has been subjected to a long history of management for wood production. Here, we examined the cumulative impacts of logging on older forests in terms of area, distribution and patch configuration in the managed forest zones of the Eastern Canadian provinces of Ontario and Quebec. We also examined the consequences of these cumulative impacts on a once widely distributed and now threatened species, the woodland caribou (Rangifer tarandus caribou). The cumulative area of recently logged forest (since ~1976) was 14,024,619 ha, with 8,210,617 ha in Quebec and 5,814,002 ha in Ontario. The total area of older forests was 21,249,341 ha, with 11,840,474 ha in Quebec and 9,408,867 ha in Ontario. Patch statistics revealed that there were 1,085,822 older forests with core patches < 0.25 ha and an additional 603,052 < 1.0 ha. There were 52 > 10,00–50,000 ha and 8 < 50,000 ha. Older forest patches (critical caribou habitat) in the 21 local population ranges totalled 6,103,534 ha, distributed among ~387,102 patches with 362,933 < 10 ha and 14 > 50,000 ha. The median percentage of local population ranges that was disturbed was 53.5%, with Charlevoix having the maximum (90.3%) and Basse Côte-Nord the least (34.9%). Woodland caribou local population ranges with disturbed suitable habitats >35% are considered unable to support self-sustaining populations. We found that for the 21 caribou local population ranges examined, 3 were at very high risk (>75% area disturbed), 16 at high risk (>45 ≤ 75% area disturbed), and 2 at low risk (≤35% area disturbed). Major changes are needed in boreal forest management in Ontario and Quebec for it to be ecologically sustainable, including a greater emphasis on protection and restoration for older forests, and to lower the risks for caribou populations. [ABSTRACT FROM AUTHOR]

The long‐term conservation of species at risk relies on numerous, and often concurrent, management actions to support their recovery. Generally, these actions are habitat‐based while others are focused on a species' position within its ecological community. Less studied are the impacts from human presence, despite evidence that human activity may reduce the area functionally available for occupancy or resource acquisition. In the winter of 2020/2021, COVID‐19‐related travel restrictions led to a reduction in helicopter‐assisted back‐country skiing (heli‐skiing). We examined how these reductions in heli‐skiing (termed the anthropause) affected the movement ecology and resource selection of southern mountain caribou (Rangifer tarandus caribou) as compared to two prior years (2018/2019 and 2019/2020) and the following year when heli‐skiing resumed (2021/2022). We found that home‐range size was on average 80–120% larger during the anthropause than in years of normal heli‐ski operations. Movement rates also varied among periods, with movement during the anthropause (11.9 km2/day) being higher than in 2019/2020 (7.8 km2/day) and 2021/2022 (8.7 km2/day), though similar to 2018/2019 (12.2 km2/day). Resource selection among periods did not differ, with caribou consistently selecting old forests, high elevations and gentle terrain. These results suggest that back‐country recreation, specifically heli‐skiing, may be limiting access to resources for southern mountain caribou. This limitation arises through reduced home‐range size within suitable late‐winter habitat, relative to when heli‐skiing is reduced or not occurring – consistent with Encounter Theory. While the demographic effects of reduced home‐range size and movement were not examined here, reduced access to resources likely compounds other stressors known to affect population viability of caribou. The results of this study demonstrate the impact that recreation can have on wildlife and highlight the need to consider heli‐skiing and other forms of recreation when developing recovery plans. [ABSTRACT FROM AUTHOR]

The Canadian boreal forest biome has been subjected to a long history of management for wood production. Here, we examined the cumulative impacts of logging on older forests in terms of area, distribution and patch configuration in the managed forest zones of the Eastern Canadian provinces of Ontario and Quebec. We also examined the consequences of these cumulative impacts on a once widely distributed and now threatened species, the woodland caribou (Rangifer tarandus caribou). The cumulative area of recently logged forest (since ~1976) was 14,024,619 ha, with 8,210,617 ha in Quebec and 5,814,002 ha in Ontario. The total area of older forests was 21,249,341 ha, with 11,840,474 ha in Quebec and 9,408,867 ha in Ontario. Patch statistics revealed that there were 1,085,822 older forests with core patches < 0.25 ha and an additional 603,052 < 1.0 ha. There were 52 > 10,00–50,000 ha and 8 < 50,000 ha. Older forest patches (critical caribou habitat) in the 21 local population ranges totalled 6,103,534 ha, distributed among ~387,102 patches with 362,933 < 10 ha and 14 > 50,000 ha. The median percentage of local population ranges that was disturbed was 53.5%, with Charlevoix having the maximum (90.3%) and Basse Côte-Nord the least (34.9%). Woodland caribou local population ranges with disturbed suitable habitats >35% are considered unable to support self-sustaining populations. We found that for the 21 caribou local population ranges examined, 3 were at very high risk (>75% area disturbed), 16 at high risk (>45 ≤ 75% area disturbed), and 2 at low risk (≤35% area disturbed). Major changes are needed in boreal forest management in Ontario and Quebec for it to be ecologically sustainable, including a greater emphasis on protection and restoration for older forests, and to lower the risks for caribou populations.

Wetlands and predation in boreal ecosystems play essential roles throughout the breeding season for bird assemblages. We found a positive association of beaver activity and a negative influence of American red squirrels (Tamiasciurus hudsonicus) on bird assemblages. We used a multispecies hierarchical model to investigate whether bird communities differ between two major wetland habitats in boreal Canada: beaver ponds and peatland ponds. In addition to including variables such as forest cover and latitude, we adopted a structural equation model approach to estimate the occupancy of American red squirrels and its potential influence on bird communities. Using automated recording stations deployed at 50 ponds, we detected 96 bird species in 2018 and 2019. Bird species were grouped into four taxonomic guilds according to their habitat successional requirements: early successional species, late successional species, generalists, and wetland species. Beaver ponds harbored higher species richness, a pattern driven primarily by early successional species. The occupancy of almost a quarter of the species was lower in the presence of red squirrels. Late successional species responded positively to the cover of forest surrounding the pond. Our results highlight the value of considering acoustic data of red squirrels to quantify habitat quality in boreal forests. We conclude that beaver activity shapes bird assemblages through modification of their habitat, and that some bird guilds are associated negatively with the presence of American red squirrels. [ABSTRACT FROM AUTHOR]

Fragmentation of the boreal forest by linear features, including seismic lines, has destabilized predator–prey dynamics, resulting in the decline of woodland caribou (Rangifer tarandus caribou) populations. Restoration of human‐altered habitat has therefore been identified as a critical management tool for achieving self‐sustaining woodland caribou populations. However, only recently has testing of the response of caribou and other wildlife to restoration activities been conducted. Early work has centered around assessing changes in wildlife use of restored seismic lines. We evaluated whether restoration reduces the movement rates of predators and their associated prey, which is expected to decrease predator hunting efficiency and ultimately reduce caribou mortality. We developed a new method for using cameras to measure fine‐scale movement by measuring speed as animals traveled between cameras in an array. We used our method to quantify speed of caribou, moose (Alces alces), bears (Ursus americanus), and wolves (Canis lupus) on treated (restored) and untreated seismic lines. Restoration treatments reduced travel speeds along seismic lines of wolves by 1.38 km/h, bears by 0.55 km/h, and caribou by 1.57 km/h, but did not reduce moose travel speeds. Reduced predator and caribou speeds on treated seismic lines are predicted to decrease encounter rates between predators and caribou and thus lower caribou kill rates. However, further work is needed to determine whether reduced movement rates result in reduced encounter rates with prey, and ultimately reduced caribou mortality. [ABSTRACT FROM AUTHOR]

In boreal forests of North America, land managers often carry out preventive treatments of forest fuel for the protection of human infrastructure from wildfires. However, these treatments may negatively affect other ecosystem services, such as the capacity to sustain wildlife populations. Here, we examine the efficacy of a strategy aimed at preserving a critical movement corridor for boreal woodland caribou (Rangifer tarandus caribou) in northern Québec, Canada, by raising high-voltage power line conductors above the forest canopy. To assess the interplay between the caribou protection objectives and a reduction in power line's exposure to wildfires, we developed an optimization model that combines the objectives of protecting the power line from wildfires via fuel treatments and maintaining a suitable movement corridor for caribou. The model combines a critical node detection (CND) problem with a habitat connectivity problem that allocates a minimum-resistance fixed-width habitat corridor between isolated wildlife refuges. Our results identify the best locations to perform fire fuel treatments to lessen the threat of fire damage to human infrastructure while maintaining a connectivity corridor for caribou in present and future climate scenarios. The selected fuel treatment locations aimed to mitigate wildfire exposure to a power line. In small-budget solutions, the exposure of power line infrastructure to wildfires was reduced by 36–39% in current climate conditions and by 20–31% in future climate, compared with no-treatment scenarios. Despite the detrimental effects of wildfire on both the industrial asset and caribou habitat, the approach provides strategies that help achieve a compromise between these two values. Such knowledge is timely to help mitigate the negative impacts of climate change on human livelihoods and natural ecosystems.

Changes in primary productivity have the potential to substantially alter food webs, with positive outcomes for some species and negative outcomes for others. Understanding the environmental context and species traits that give rise to these divergent outcomes is a major challenge to the generality of both theoretical and applied ecology. In aquatic systems, nutrient-mediated eutrophication has led to major declines in species diversity, motivating us to seek terrestrial analogues using a large-mammal system across 598 000 km2 of the Canadian boreal forest. These forests are undergoing some of the most rapid rates of land-use change on Earth and are home to declining caribou (Rangifer tarandus caribou) populations. Using satellite-derived estimates of primary productivity, coupled with estimates of moose (Alces alces) and wolf (Canis lupus) abundance, we used path analyses to discriminate among hypotheses explaining how habitat alteration can affect caribou population growth. Hypotheses included food limitation, resource dominance by moose over caribou, and apparent competition with predators shared between moose and caribou. Results support apparent competition and yield estimates of wolf densities (1.8 individuals 1000 km−2) above which caribou populations decline. Our multi-trophic analysis provides insight into the cascading effects of habitat alteration from forest cutting that destabilize terrestrial predator–prey dynamics. Finally, the path analysis highlights why conservation actions directed at the proximate cause of caribou decline have been more successful in the near term than those directed further along the trophic chain. [ABSTRACT FROM AUTHOR]

Protected areas are needed to conserve nature and biodiversity worldwide. The province of Québec (Canada) recently established a large wilderness area affording significant habitat protection for boreal woodland caribou (Rangifer tarandus caribou), a wide‐ranging species at risk. We describe a decision support framework combining ecological modeling with socioeconomic constraints that ultimately led to the creation of this protected area. Multiple criteria were used to identify candidate protected areas for boreal caribou. These had to be large in size (>10,000 km2) and located in regions where available high‐quality habitat was threatened by development pressures. Candidate areas also had to contribute substantively to the maintenance of functional habitat connectivity, be exempt from major industrial developments and recent fires, and required evidence of recent use by caribou. Five candidate protected areas emerged from this exercise. Key regional stakeholders were consulted, thereby strengthening advocacy for land designation, and boundaries were refined through their input, which helped further reduce socioeconomic conflicts. This process involved difficult compromises, but eventually led to the legal designation on March 4, 2021 of a new protected area for boreal caribou known as the Caribous‐Forestiers‐de‐Manouane‐Manicouagan. We show how our science‐informed decision support framework was instrumental in the success of this endeavor, and describe the obstacles overcame in the process, so that other jurisdictions may draw from this experience in their efforts to achieve similar conservation goals. [ABSTRACT FROM AUTHOR]

Abstract Protected areas are needed to conserve nature and biodiversity worldwide. The province of Québec (Canada) recently established a large wilderness area affording significant habitat protection for boreal woodland caribou (Rangifer tarandus caribou), a wide‐ranging species at risk. We describe a decision support framework combining ecological modeling with socioeconomic constraints that ultimately led to the creation of this protected area. Multiple criteria were used to identify candidate protected areas for boreal caribou. These had to be large in size (>10,000 km2) and located in regions where available high‐quality habitat was threatened by development pressures. Candidate areas also had to contribute substantively to the maintenance of functional habitat connectivity, be exempt from major industrial developments and recent fires, and required evidence of recent use by caribou. Five candidate protected areas emerged from this exercise. Key regional stakeholders were consulted, thereby strengthening advocacy for land designation, and boundaries were refined through their input, which helped further reduce socioeconomic conflicts. This process involved difficult compromises, but eventually led to the legal designation on March 4, 2021 of a new protected area for boreal caribou known as the Caribous‐Forestiers‐de‐Manouane‐Manicouagan. We show how our science‐informed decision support framework was instrumental in the success of this endeavor, and describe the obstacles overcame in the process, so that other jurisdictions may draw from this experience in their efforts to achieve similar conservation goals.

Lethal population control has a history of application to wildlife management and conservation. There is debate about the efficacy of the practice, but more controversial is the ethical justification and methods of killing one species in favor of another. This is the situation facing the conservation of woodland caribou (Rangifer tarandus caribou) in Canada. Across multiple jurisdictions, large numbers of wolves (Canis lupus), and to a lesser extent bears (Ursus americanus) and coyotes (C. latrans), are killed through trapping, poisoning or aerial shooting to halt or reverse continued declines of woodland caribou. While there is evidence to support the effectiveness of predator management as a stop‐gap solution, questions remain about the extent to which this activity can make a meaningful contribution to long‐term recovery. Also, there are myriad ethical objections to the lethal removal of predators, even if that activity is in the name of conservation. Debates about predator management, just one of numerous invasive actions for maintaining caribou, are made even more complex by the conflation of ethics and efficacy. Ultimately, long‐term solutions for the recovery of caribou require governments to stop delaying difficult decisions that address the real causes of population decline, habitat change. [ABSTRACT FROM AUTHOR]

Non‐renewable resource extraction contributes greatly to degradation of wildlife habitats in boreal landscapes. In western Canada, oil and gas exploration and extraction have left a dense network of linear disturbances (seismic lines) and abandoned well pads that have fragmented boreal forest. Among multiple ecological effects, these disturbances have increased predator access to the preferred habitat of some wildlife taxa, most notably boreal woodland caribou, resulting in population declines. Restoration of seismic lines and abandoned well pads is a critical activity to improve the recovery of woodland caribou populations. We present a linear programming model that optimally allocates restoration efforts to maximize the access of caribou to nearby undisturbed habitat in a fragmented landscape. We applied the model to examine restoration scenarios in the Cold Lake First Nations area in northeastern Alberta, Canada, which includes caribou habitat but also areas of active oil and gas extraction. The model depicts the landscape as a network of interconnected habitat patches and combines three network flow sub‐problems. The first sub‐problem enforces the spatial connectivity of the remaining network of unrestored sites. The second sub‐problem maximizes access to suitable habitat from the restored locations and the third sub‐problem ensures the allocation of restoration activities in as few spatially contiguous restoration projects as possible. The approach is generalizable and applicable to assist restoration planning in other resource extraction regions and for other taxa. [ABSTRACT FROM AUTHOR]

Protecting wildlife corridors is a common management problem in regions of industrial forestry. In boreal Canada, human disturbances have negatively affected woodland caribou populations (Rangifer tarandus caribou), which prefer to function in large undisturbed areas. We present a linear programming model that allocates a fixed-width corridor between isolated caribou ranges and estimates its impact on harvest activities. Our corridor placement problem minimizes total resistance for caribou passing through the corridor, which is protected by a prohibition on all economic activities. We link this corridor placement problem with a harvest planning problem that maximizes the net revenues from harvest minus the cost of building and maintaining forest access roads. We depict gradual expansion of the forest road network over time as a multi-temporal network flow problem. We applied our approach to explore corridor options for connecting caribou populations in the Lake Superior Coast Range, with the Nipigon and Pagwachuan Ranges in the Kenogami-Pic Forest, in northern Ontario, Canada. Our results revealed two locations where corridor placement is cost-effective. Optimal corridor placement depends on the perception of the severity of the impact of roads on caribou populations and decision-making objectives. When the negative impact of roads is perceived to be high and/or maximizing harvest revenues is important, the optimal corridor location is in the eastern part of the study area. However, it is optimal to place the corridor in the western part of the area when the negative impact of roads is perceived to be small or the shortest corridor is desired. [ABSTRACT FROM AUTHOR]

Forest logging has contributed to the decline of several woodland caribou populations by causing the fragmentation of mature coniferous stands. Such habitat alterations could be worsened by spruce budworm (SBW) outbreaks. Using 6201 vegetation plots from provincial inventories conducted after the last SBW outbreak (1968–1992) in boreal forests of Québec (Canada), we investigated the influence of SBW‐caused tree defoliation and mortality on understory vegetation layers relevant to woodland caribou and its main predators. We found a positive association between severe outbreaks and the cover of most groups of understory plant species, especially in stands that were dominated by balsam fir before the outbreak, where a high canopy openness particularly benefited relatively fast‐growing deciduous plants. Such increases in early successional vegetation could provide high‐quality forage for moose, which is likely to promote higher wolf densities and increase predation pressure on caribou. SBW outbreaks may thus negatively affect woodland caribou by increasing predation risk, the main factor limiting caribou populations in managed forests. For the near future, we recommend updating the criteria used to define critical caribou habitat to consider the potential impacts of spruce budworm defoliation. [ABSTRACT FROM AUTHOR]

In western Canada, decades of oil-and-gas exploration have fragmented boreal landscapes with a dense network of linear forest disturbances (seismic lines). These seismic lines are implicated in the decline in wildlife populations that are adapted to function in unfragmented forest landscapes. In particular, anthropogenic disturbances have led to a decline of woodland caribou populations due to increasing predator access to core caribou habitat. Restoration of seismic lines aims to reduce the landscape fragmentation and stop the decline of caribou populations. However, planning restoration in complex landscapes can be challenging because it must account for a multitude of diverse aspects. To assist with restoration planning, we present a spatial network optimization approach that selects restoration locations in a fragmented landscape while addressing key environmental and logistical constraints. We applied the model to develop restoration scenarios in the Redrock-Prairie Creek caribou range in northwestern Alberta, Canada, which includes a combination of caribou habitat and active oil-and-gas and timber extraction areas. Our study applies network optimization at two distinct scales to address both the broad-scale restoration policy planning and project-level constraints at the level of individual forest sites. We first delineated a contiguous set of coarse-scale regions where restoration is most cost-effective and used this solution to solve a fine-scale network optimization model that addresses environmental and logistical planning constraints at the level of forest patches. Our two-tiered approach helps address the challenges of fine-scale spatial optimization of restoration activities. An additional coarse-scale optimization step finds a feasible starting solution for the fine-scale restoration problem, which serves to reduce the time to find an optimal solution. The added coarse-scale spatial constraints also make the fine-scale restoration solution align with the coarse-scale landscape features, which helps address the broad-scale restoration policies. The approach is generalizable and applicable to assist restoration planning in other regions fragmented by oil-and-gas activities. • The proposed methodology can assist restoration of linear disturbances in forest landscapes. • Optimization model supports restoration decisions by accounting for both operational and wildlife conservation objectives. • The two-tier approach addresses both the broad-scale policy goals and practical planning at the level of individual sites. • The approach is applicable in areas with presence of both resource extraction activities and endangered species populations. [ABSTRACT FROM AUTHOR]

Canada's federal recovery strategy for boreal woodland caribou (Rangifer tarandus caribou) classifies areas burned by forest fire as disturbed habitat. This assignment of fire as a disturbance has potential economic and social implications across Canada, and influences plans and actions to achieve caribou conservation and recovery. Previous researchers have reported caribou avoid burned habitat, but these studies did not typically consider unburned residual patches within fire perimeters. Additionally, the implications of burned habitat on individual caribou survival is unclear. We examined resource selection by boreal woodland caribou of burns, and unburned residual patches, using global positioning system (GPS) locations for 201 caribou across 6 caribou populations in Alberta, Canada. We also examined if burned habitat affected the survival of adult female caribou. Caribou avoided burns and unburned residual patches. Increased use of burned habitats, however, did not lower the survival of adult caribou. Collectively, these results provide evidence to support current assertions that burns, and the embedded unburned residual patches are not preferred caribou habitat and increase our understanding of the implications of forest fire for caribou vital rates. Our investigation offers important information about the role of forest fire in caribou ecology and enhances the identification of disturbed habitat under recovery strategy guidelines to effectively address caribou population declines. © 2021 The Wildlife Society. : Woodland caribou in Alberta, Canada avoid burned habitat including unburned residual patches; however, there was no relationship between burned habitat use and adult female survival. This suggests fire disturbance is not a key influence of caribou population persistence, and we recommend reevaluation of the current approach listed in the federal boreal caribou recovery strategy that includes anthropogenic and fire disturbance in a cumulative assessment of disturbed habitat. [ABSTRACT FROM AUTHOR]

Seasonal migration is intrinsically connected to the balance of survival and reproduction, but whether migratory behavior influences species' position on the slow-fast continuum of life history is poorly understood. We found that boreal-breeding birds that migrate long distances exhibit higher annual adult survival and lower annual reproductive investment relative to co-distributed boreal species that migrate shorter distances to winter closer to their breeding grounds. Our study uses "vital rates" data on reproductive output and survivorship compiled from the literature for a species assemblage of 45 species of mostly passerine birds. These species breed sympatrically in North American boreal forests but migrate to a diversity of environments for the northern winter. After controlling for body size and phylogeny, migration distance and apparent annual adult survival are positively related across species. Both migration distance and survival are positively correlated with wintering in environments that are warmer, wetter, and greener. At the same time, longer migrations are associated with reduced time spent on the breeding grounds, lower clutch sizes, and lower fecundity (clutch size × maximum number of broods per year). Although seasonal migration is often associated with high mortality, our results suggest that long-distance migration imposes selection pressures that both confer and demand high adult survival rates. That is, owing to the reproductive cost of long-distance migration, this strategy can only persist if balanced by high adult survival. Our study supports the idea that migration evolves to promote survival of species breeding in seasonal environments. In boreal birds, the evolution of the longest migrations yields the highest survival, but at an inherent cost to annual fecundity. Our results therefore reveal migratory distance as a fundamental axis of the slow-fast continuum that predicts, and is inextricable from, the balance of survival and reproduction. [ABSTRACT FROM AUTHOR]

Group size can vary in relation to population density, habitat, and season. Habitat and season may also interact with population density and affect group size through varying foraging benefits of social aggregation in different ecological contexts. We tested the hypothesis that group size varies across ecological contexts, including population density, habitat type, and season, for woodland caribou (Rangifer tarandus) in ten herds over 25 years in Newfoundland, Canada. We predicted that group size would increase as a function of population density. Based on the foraging benefits of social aggregation, we predicted larger groups as habitat openness increased because open areas tend to have higher quality foraging resources. We predicted larger groups during winter when foraging resources are covered in snow because caribou and other social animals exploit social information about the location of foraging resources. In contrast to our prediction, group size decreased as a function of population density. In support of our prediction, group size was larger in winter than calving and summer, and we found that group size increased with habitat openness in some, but not all, cases. Patterns of animal grouping are context-dependent and the additive effect of different ecological contexts on variation in group size informs our understanding of the implicit trade-offs between competition, predation risk, and profitability of forage. Animal groups contribute to the social environment. The profitability of the social environment changes with ecological context, and may be reflected in changing group sizes. For example, population density, habitat, and season are important contexts across which group sizes may vary. We tested how ecological context could affect group size in caribou. We found that group size decreased with increasing population density, groups were larger in winter and that groups increased in size across habitat openness. Articulating context-dependent trends in group size lends precision to understanding how ecological context shapes the social environment. [ABSTRACT FROM AUTHOR]

Woodland caribou (Rangifer tarandus) are threatened in Alberta in part due to the development of oil and gas resources. To inform best management practices for caribou, we assessed how proximity to wellsites influenced caribou habitat selection, and whether habitat selection varied across wellsite activity phases (i.e., drilling, producing, and inactive). We used location data from 37 GPS-collared caribou monitored between 2007 and 2013 in west-central Alberta to model habitat selection. Our results suggest the influence of wellsites on caribou habitat selection are temporally dynamic. The largest impacts occur when human activity at wellsites is greatest, however wellsites continue to influence caribou habitat selection after human activity ceases. Caribou avoided wellsites, and avoidance increased relative to the degree of activity at the nearest wellsite. During early winter, caribou avoided wellsites in the drilling phase more than inactive and producing wellsites. During late winter, caribou avoided wellsites in producing phases more than inactive wellsites. Caribou may benefit from management practices that include i) seasonal timing restrictions on drilling, ii) reductions of human activity at wellsites, whether in duration or intensity, iii) land-use planning to coordinate the placement of wellsites to minimize impacts to caribou and their habitat, and iv) prompt and effective restoration of wellsites to match original habitat conditions once production has stopped.

Habitat loss is often the ultimate cause of species endangerment and is also a leading factor inhibiting species recovery. For this reason, species‐at‐risk legislation, policies and plans typically focus on habitat conservation and restoration as mechanisms for recovery. To assess the effectiveness of these instruments in decelerating habitat loss, we evaluated spatiotemporal habitat changes for an iconic endangered species, woodland caribou (Rangifer tarandus caribou). We quantified changes in forest cover, a key proxy of caribou habitat, for all caribou subpopulations in Alberta and British Columbia, Canada. Despite efforts under federal and provincial recovery plans, and requirements listed under Canada's Species at Risk Act, caribou subpopulations lost twice as much habitat as they gained during a 12‐year period (2000–2012). Drivers of habitat loss varied by ecotype, with Boreal and Northern Mountain caribou affected most by forest fire and Southern Mountain caribou affected more by forest harvest. Our case study emphasizes critical gaps between recovery planning and habitat management actions, which are a core expectation under most species‐at‐risk legislation. Loss of caribou habitat from 2000 to 2018 has accelerated. Linear features within caribou ranges have also increased over time, particularly seismic lines within Boreal caribou ranges, and we estimated that only 5% of seismic lines have functionally regenerated. Our findings support the idea that short‐term recovery actions such as predator reductions and translocations will likely just delay caribou extinction in the absence of well‐considered habitat management. Given the magnitude of ongoing habitat change, it is clear that unless the cumulative impacts of land‐uses are effectively addressed through planning and management actions that consider anthropogenic and natural disturbances, we will fail to achieve self‐sustaining woodland caribou populations across much of North America. [ABSTRACT FROM AUTHOR]

Abstract Habitat loss is often the ultimate cause of species endangerment and is also a leading factor inhibiting species recovery. For this reason, species‐at‐risk legislation, policies and plans typically focus on habitat conservation and restoration as mechanisms for recovery. To assess the effectiveness of these instruments in decelerating habitat loss, we evaluated spatiotemporal habitat changes for an iconic endangered species, woodland caribou (Rangifer tarandus caribou). We quantified changes in forest cover, a key proxy of caribou habitat, for all caribou subpopulations in Alberta and British Columbia, Canada. Despite efforts under federal and provincial recovery plans, and requirements listed under Canada's Species at Risk Act, caribou subpopulations lost twice as much habitat as they gained during a 12‐year period (2000–2012). Drivers of habitat loss varied by ecotype, with Boreal and Northern Mountain caribou affected most by forest fire and Southern Mountain caribou affected more by forest harvest. Our case study emphasizes critical gaps between recovery planning and habitat management actions, which are a core expectation under most species‐at‐risk legislation. Loss of caribou habitat from 2000 to 2018 has accelerated. Linear features within caribou ranges have also increased over time, particularly seismic lines within Boreal caribou ranges, and we estimated that only 5% of seismic lines have functionally regenerated. Our findings support the idea that short‐term recovery actions such as predator reductions and translocations will likely just delay caribou extinction in the absence of well‐considered habitat management. Given the magnitude of ongoing habitat change, it is clear that unless the cumulative impacts of land‐uses are effectively addressed through planning and management actions that consider anthropogenic and natural disturbances, we will fail to achieve self‐sustaining woodland caribou populations across much of North America.

Abstract 1. Endangered species policies and their associated recovery documents and management actions do not always sufficiently address the importance of migratory behaviour and seasonal ranges for imperilled populations. 2. Using a telemetry location dataset spanning 1981–2018, we tested for changes in prevalence of migratory tactics (resident, migrant) over time, switching between tactics, shifts in seasonal space use including migration corridors, and survival consequences of migrant and resident tactics for 237 adult female endangered woodland mountain caribou in one population in western Canada. 3. Over more than three decades, the proportion of individuals displaying annual migration to the low elevation forested winter range declined from nearly 100%–38%. Correspondingly, there was a strong switch away from being migrant to being year‐round residents at high elevation. 4. These behavioural changes corresponded to abandonment of low elevation winter ranges in association with increasing levels of anthropogenic land uses, including forestry and oil and gas developments. Furthermore, there were no identifiable migration corridors to target for migratory route protection. 5. These shifts translated to lower survival rates, particularly for caribou demonstrating resident tactics, consistent with recent declines of the caribou population. That migrants switched to residency in their largely undisturbed summer range, despite lower survival, indicates maladaptive habitat selection consistent with recent patterns of mountain caribou extirpations. 6. Globally, endangered species policies and their associated recovery plans and management actions often do not explicitly consider the challenge of protecting migratory species. Effective conservation of migratory species requires protecting critical habitats needed for the entire life history of the species, including all seasonal ranges and migratory habitat.

Industrial forestry in boreal regions increases fragmentation and may decrease the viability of some wildlife populations, particularly the woodland caribou, Rangifer tarandus caribou. Caribou protection often calls for changes in forestry practices, which may increase the cost and reduce the available timber supply. We present a linear programming model that assesses the trade‐off between habitat protection and harvesting objectives by combining harvest scheduling and optimal habitat connectivity problems. We formulate the habitat connectivity model as a network flow problem that maximizes the amount of habitat connected over a desired time span in a forested landscape, while the forestry objective maximizes net undiscounted revenues from timber harvest subject to even harvest flow and environmental sustainability constraints. We applied the approach to explore the trade‐off between caribou habitat protection and harvesting goals in the Armstrong‐Whitesand Forest, Ontario, Canada, a boreal forest area with prime caribou habitat. Our model also incorporates Dynamic Caribou Harvesting Scheduling (DCHS), a harvest policy currently in a place in Ontario that aims to balance the forest management and caribou protection goals in northern boreal regions. In our study area, the implementation of DCHS appears to have relatively minor impact on timber supply cost. By comparison, maximizing the protection of caribou habitat would lead to a noticeable increase of the mill gate timber cost by $3.3 m−3 on average, while enabling habitat protection in an additional 5.0%–9.5% of the range area. Our model is generalizable and can be adapted for assessing habitat recovery and harvest goals in other regions. Recommendations for Resource Managers:Incorporating the concept of long‐term habitat connectivity into forest planning can help reduce the negative impacts of harvest activities on caribou populations.Prioritizing habitat connectivity leads to a small increase in the overall harvest area because harvest has to be allocated to less productive and more geographically isolated sites to protect prime wildlife habitat containing old conifer stands.Maximizing the habitat protection would lead to a noticeable increase of the timber supply cost (by $3.3 m−3 on average), while enabling moderate increase of the protected habitat area (i.e., an additional 5.0%–9.5% of the range area).Implementation of Dynamic Caribou Harvest Schedules, which is the current harvesting policy in Ontario's boreal forests when caribou populations are present, causes only a minor increase of the timber supply cost in our study area. [ABSTRACT FROM AUTHOR]

Changes in primary productivity have the potential to substantially alter food webs, with positive outcomes for some species and negative outcomes for others. Understanding the environmental context and species traits that give rise to these divergent outcomes is a major challenge to the generality of both theoretical and applied ecology. In aquatic systems, nutrient-mediated eutrophication has led to major declines in species diversity, motivating us to seek terrestrial analogues using a large-mammal system across 598 000 km2 of the Canadian boreal forest. These forests are undergoing some of the most rapid rates of land-use change on Earth and are home to declining caribou (Rangifer tarandus caribou) populations. Using satellite-derived estimates of primary productivity, coupled with estimates of moose (Alces alces) and wolf (Canis lupus) abundance, we used path analyses to discriminate among hypotheses explaining how habitat alteration can affect caribou population growth. Hypotheses included food limitation, resource dominance by moose over caribou, and apparent competition with predators shared between moose and caribou. Results support apparent competition and yield estimates of wolf densities (1.8 individuals 1000 km−2) above which caribou populations decline. Our multi-trophic analysis provides insight into the cascading effects of habitat alteration from forest cutting that destabilize terrestrial predator–prey dynamics. Finally, the path analysis highlights why conservation actions directed at the proximate cause of caribou decline have been more successful in the near term than those directed further along the trophic chain. [ABSTRACT FROM AUTHOR]

Adult female survival and calf recruitment influence population dynamics, but there is limited information on calving and neonatal mortality of boreal woodland caribou (Rangifer tarandus caribou; caribou) in Ontario, Canada. We identified calf parturition sites and 5‐week neonatal mortality using a movement‐based approach across 3 northern Ontario study regions (Pickle Lake, Nakina, and Cochrane) that vary in their capacity to support caribou populations. In comparing 22 caribou‐years of video‐collar footage during 2010–2013 to predictions of the movement‐based approach, we found live parturition events were 100% correctly classified, date of parturition was within 1.08 ± 0.28 (x¯ ± SE) days, and mortality events up to 5 weeks postpartum were 88% correctly classified. Across study regions, 87% of 186 caribou were pregnant and 76% of 107 caribou‐years indicated birth events with median parturition dates a week later in Cochrane (23 May) than in Pickle Lake (17 May) and Nakina (16 May). Based on selection ratios of caribou‐years with calves‐at‐heel (n = 80), caribou consistently selected for lowlands and closed‐canopied forests and mostly against early‐seral stands (<20 yrs old) and areas near linear features during the neonatal and the post‐neonatal period (up to 35 days postpartum). Based on the video footage and movement models, 30% of 81 caribou‐years that indicated live births also showed females lost their calf within the first 5 weeks postpartum, with higher risk of neonatal mortality associated with increased use of lowlands and greater postpartum movement rates. This study provides informative metrics of caribou reproduction across northern Ontario that will contribute to future population modeling and identifies important landscape features to be considered in future industrial development and land use planning for caribou conservation. © 2020 The Wildlife Society. Parturition and neonatal mortality rates can be predicted accurately from movement rates. Caribou selected calving (neonatal and post‐neonatal) areas to minimize predation risk, but greater use of lowlands and increased movement rates postpartum increased risk of neonatal mortality. [ABSTRACT FROM AUTHOR]

Boreal forests provide numerous ecological services, including the ability to store large amounts of carbon, and are of significance to global biodiversity. Increases in industrial activities in boreal landscapes since the mid‐20th century have added to concerns over biodiversity loss and climate change. Boreal forests are home to dwindling populations of boreal caribou Rangifer tarandus caribou in Canada, a species at risk that requires large, undisturbed landscapes for persistence. In 2012, the Canadian government defined critical habitat for boreal caribou by relating calf recruitment to disturbances. Some have questioned whether the recruitment relationship can be extrapolated beyond the environmental conditions represented in the analysis.We examined the effects of human disturbances and fire (alone and in combination) on variation in recruitment and adult female survival using data from 58 study areas in Canada. Top models were used in aspatial scenarios of landscape change to evaluate the efficacy of the critical habitat definition in achieving the recovery objectives for boreal caribou in two contrasting landscapes: Little Smoky, dominated by high levels of human disturbances, and the northern boreal shield of Saskatchewan (SK1), dominated by fire.The top recruitment model suggested the negative effect of fire was three to four times smaller than human disturbances. The top adult female survival model included human disturbances only. These results re‐affirm that human disturbances are the primary factor contributing to boreal caribou declines.Our aspatial scenarios suggested that undisturbed habitat would have to increase to ≥68% for Little Smoky to maintain a self‐sustaining population of boreal caribou with some degree of certainty. In contrast, the SK1 population was self‐sustaining with 40% undisturbed habitat when fire disturbance predominates, but could become vulnerable with increases in human disturbances (8%–9%).Policy implications. Boreal caribou are listed as threatened under Canada's Species at Risk Act. Our results suggest that the 65% undisturbed critical habitat designation in Canada's boreal caribou Recovery Strategy may serve as a reasonable proxy for achieving self‐sustaining populations of boreal caribou in landscapes dominated by human disturbances. However, some populations may be less or more vulnerable, as illustrated by the scenarios in a landscape dominated by fire (SK1). Continued population monitoring will be essential to assessing the effectiveness of land management strategies developed for boreal caribou recovery, especially with climate change. [ABSTRACT FROM AUTHOR]

Caribou (Rangifer tarandus) populations are sympatric with Cougars (Puma concolor) in only a few areas, primarily in western Canada. Records of Cougar-Caribou interactions are limited and no published accounts describe Cougar predation on the shallow-snow, terrestrial-lichen-eating Northern Mountain Caribou (Rangifer tarandus caribou), referred to as Designatable Unit (DU) 7 by the Committee on the Status of Endangered Wildlife in Canada. In 2018 and 2019, two incidents of confirmed Cougar predation on radio-collared Caribou were documented in the declining Itcha-Ilgachuz subpopulation in west-central British Columbia. To the best of our knowledge, this is the first published record of Cougar predation on DU7 Northern Mountain Caribou. Increased landscape disturbance and climate change may be increasing apparent competition between deer (Odocoileus spp.), feral Horses (Equus ferus caballus), and Caribou, leading to Cougar predation in areas of Caribou range where it previously has not been documented. Cougar predation may become a conservation concern, as declining Caribou herds are susceptible to any increased predation pressure. [ABSTRACT FROM AUTHOR]

When adopted, wildlife protection policies in Canadian forests typically cover large areas and affect multiple economic agents working in these landscapes. Such measures are likely to increase the costs of timber for forestry companies operating in the area, which may hinder their acceptance of the policies unless harvesting remains profitable. We propose a bi-level wildlife protection problem that accounts for the profit-maximizing behavior of forestry companies operating in an area subject to protection. We consider the regulator with a wildlife protection mandate and forestry companies licensed to harvest public forest lands. We depict the relationship between the regulator and forestry companies as a leader-follower Stackelberg game. The leader sets the protected area target for each license area and the followers adjust their strategies to maximize payoffs while meeting the protection target set by the leader. The leader’s objective is to maximize the area-wide protection of spatially contiguous habitat while accounting for the followers’ profit-maximizing behavior. We apply the approach to investigate habitat protection policies for woodland caribou in the Churchill range, Ontario, Canada. We compare the game-theoretic solutions with solutions that do not consider the forest companies’ objectives and also with solutions equalizing the revenue losses among the companies.

One of the most challenging tasks in wildlife conservation and management is to clarify how spatial variation in land cover due to anthropogenic disturbance influences wildlife demography and long‐term viability. To evaluate this, we compared rates of survival and population growth by woodland caribou (Rangifer tarandus caribou) from 2 study sites in northern Ontario, Canada that differed in the degree of anthropogenic disturbance because of commercial logging and road development, resulting in differences in predation risk due to gray wolves (Canis lupus). We used an individual‐based model for population viability analysis (PVA) that incorporated adaptive patterns of caribou movement in relation to predation risk and food availability to predict stochastic variation in rates of caribou survival. Field estimates of annual survival rates for adult female caribou in the unlogged (x¯= 0.90) and logged (x¯= 0.76) study sites recorded during 2010–2014 did not differ significantly (P > 0.05) from values predicted by the individual‐based PVA model (unlogged: x¯ = 0.87; logged: x¯= 0.79). Outcomes from the individual‐based PVA model and a simpler stage‐structured matrix model suggest that substantial differences in adult survival largely due to wolf predation are likely to lead to long‐term decline of woodland caribou in the commercially logged landscape, whereas the unlogged landscape should be considerably more capable of sustaining caribou. Estimates of population growth rates (λ) for the 2010–2014 period differed little between the matrix model and the individual‐based PVA model for the unlogged (matrix model x¯ = 1.01; individual‐based model x¯ = 0.98) and logged landscape (matrix model x¯ = 0.88; individual‐based model x¯ = 0.89). We applied the spatially explicit PVA model to assess the viability of woodland caribou across 14 woodland caribou ranges in Ontario. Outcomes of these simulations suggest that woodland caribou ranges that have experienced significant levels of commercial forestry activities in the past had annual growth rates <0.89, whereas caribou ranges that had not experienced commercial forestry operations had population growth rates >0.96. These differences were strongly related to regional variation in wolf densities. Our results suggest that increased wolf predation risk due to anthropogenic disturbance is of sufficient magnitude to cause appreciable risk of population decline in woodland caribou in Ontario. © 2020 The Authors. The Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society. We used matrix and individual‐based population viability assessment models to compare the demography of woodland caribou populations in Ontario in unlogged landscapes with those in logged landscapes. Our results suggest that increased wolf predation risk due to anthropogenic disturbance is of sufficient magnitude to cause appreciable risk of population decline in woodland caribou in Ontario. [ABSTRACT FROM AUTHOR]

Network theory increasingly informs wildlife conservation in disturbed landscapes, but with concern increasingly expressed about its application to real‐world situations. The theory predicts that the connectivity of scale‐free networks should be particularly sensitive to the disturbance of highly connected nodes (i.e. hubs). This expectation relies on complete patch removal, thus restraining its application to the last of several steps involved in habitat fragmentation, and overlooks potential reconnection of patches after disturbance (i.e. rewiring).We performed a landscape‐scale experiment to evaluate the robustness of scale‐free spatial networks of woodland caribou (Rangifer tarandus caribou) to logging activity. We built caribou networks before and after disturbance using a mechanistic model of inter‐patch movements and differentiated networks disturbed in their hubs and non‐hubs. We applied a reaction–advection–diffusion model to networks before and after disturbance to account for the spatio‐temporal dynamics of caribou movement within the networks and anticipate their space use. We validated network and space‐use predictions using empirical estimates from GPS relocations of caribou. Using the validated predictions, we compared topological network measures before and after disturbance to quantify changes in connectivity within the networks according to the type of disturbed nodes (i.e. hubs or non‐hubs) and assessed space‐use reorganization. We used control networks, for which no disturbance occurred in the before–after timeframe of the study, in the latter analysis to get a baseline rate of change.Disturbances due to logging activity typically resulted in fragmentation and shrinkage instead of complete patch removal. Independently to the type of disturbed nodes, caribou rewired their network using remnant patches from the fragmentation process. Consequently, topological network measures generally did not differ between before and after disturbance, such that caribou networks displayed some robustness to logging activity due to the rewiring process.Space‐use reorganization was greater, however, when hubs were disturbed in comparison with non‐hubs and controls. Even though caribou rewired their networks, they revisited less patches after the disturbance of hubs.A naive application of network theory (i.e. without potential rewiring and using complete patch removal), to assess spatial network robustness, may be inappropriate during most steps of the fragmentation process because of the rewiring process. Indeed, network rewiring facilitated by the presence of remnant patches can enhance spatial network robustness, in comparison with no rewiring. In addition, species‐specific functional connectivity should be accounted for when anticipating the rewiring process and animal space use within disturbed networks. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Understanding how organisms distribute themselves in response to interacting species, ecosystems, climate, human development and time is fundamental to ecological study and practice. A measure to quantify the relationship among organisms and their environments is intensity of use: the rate of use of a specific resource in a defined unit of time. Estimating the intensity of use differs from estimating probabilities of occupancy or selection, which can remain constant even when the intensity of use varies. We describe a method to evaluate the intensity of use across conditions that vary in both space and time. We demonstrate its application on a large mammal community where linear developments and human activity are conjectured to influence the interactions between white‐tailed deer (Odocoileus virginianus) and wolves (Canis lupus) with possible consequences on threatened woodland caribou (Rangifer tarandus caribou).We collect and quantify intensity of use data for multiple, interacting species with the goal of assessing management efficacy, including a habitat restoration strategy for linear developments. We test whether blocking linear developments by spreading logs across a 200‐m interval can be applied as an immediate mitigation to reduce the intensities of use by humans, predator and prey species in a boreal caribou range.We deployed camera traps on linear developments with and without restoration treatments in a landscape exposed to both timber and oil development. We collected a three‐year dataset and employed spatial recurrent event models to analyse intensity of use by an interacting human and large mammal community across a range of environmental and climatic conditions.Spatial recurrent event models revealed that intensity of use by humans influenced the intensity of use by all five large mammal species evaluated, and the intensities of use by wolves and deer were inextricably linked in space and time. Conditions that resist travel on linear developments had a strong negative effect on the intensity of human and large mammal use.Mitigation strategies that resist, or redirect, animal travel on linear developments can reduce the effects of resource development on interacting human and predator–prey interactions. Our approach is easily applied to other continuous time point‐based survey methodologies and shows that measuring the intensity of use within animal communities can help scientists monitor, mitigate and understand ecological states and processes. [ABSTRACT FROM AUTHOR]

Abstract Anthropogenic disturbances fragmenting wildlife habitat greatly contribute to extinction risk for many species. In western Canada, four decades of oil and gas exploration have created a network of seismic lines, which are linear disturbances where seismic equipment operates. Seismic lines cause habitat fragmentation and increase predator access to intact forest, leading to declines of some wildlife populations, particularly the threatened woodland caribou, Rangifer tarandus caribou. Restoration of forests within seismic lines is an important activity to reduce habitat fragmentation and recovery caribou. We present an optimization model with the objective of guiding landscape restoration strategies that maximize the area of connected habitat for a caribou population in a fragmented landscape. We use our model to find optimal strategies for seismic line restoration in the Cold Lake Area of Alberta, Canada, a 6726-km2 expanse of boreal forest that represents prime caribou habitat. We formulate mixed integer programming models that depict the landscape as a network of interconnected habitat patches. We develop and compare formulations that emphasize the population's local or long-distance access to habitat. Optimal restoration involves a mix of two strategies: the first establishes short-distance connections between forest patches with large areas of intact habitat and the second establishes corridors between areas with known species locations and large amounts of suitable habitat. Our approach reveals the trade-offs between these strategies and finds the optimal restoration solutions under a limited budget. The approach is generalizable and applicable to other regions and species sensitive to changes in landscape-level habitat connectivity. [ABSTRACT FROM AUTHOR]

Abstract Understanding how conservation of woodland caribou, an at-risk species for which large undisturbed areas are often proposed to maintain viable populations, can contribute to conservation of boreal biodiversity is an important consideration for an ecosystem warming at twice the global average and experiencing rapid resource development. We assess the focal or 'umbrella' value of the boreal population of woodland caribou for conservation of mammalian and avian richness (n = 432) in the boreal region of Canada by (i) evaluating co-occurrence of caribou distribution with that of boreal mammals (n = 102), birds (n = 330), at-risk mammals (n = 11) and at-risk birds (n = 47); and (ii) conducting systematic conservation planning using MARXAN software to identify minimum representative and complementary reserve networks, comprised of planning units deemed large enough (10,000 km2) for persistence of terrestrial wildlife, both at the extent of boreal caribou distribution and the entire boreal region. While boreal caribou overlap with the range of 90% of boreal birds and mammals, area-efficient networks representative of boreal diversity focus on species-rich areas south of caribou distribution and other areas that contain relatively small-ranged species. A similar pattern occurs when the MARXAN analysis focused only on caribou distribution, i.e. representative networks are preferentially located on southern herd ranges. However, this situation differs markedly to include large areas within the distribution of caribou if anthropogenic footprint on the landscape is considered as a constraint on reserve design. Efforts to sustain boreal caribou offer considerable opportunities to conserve diversity of co-occurring mammals and birds, including areas of the relatively more disturbed caribou southern ranges that have irreplaceable value in an efficient and representative pan-boreal network of reserves. The high focal value of boreal caribou for animal diversity should be considered when making decisions and policy choices about how to best allocate conservation efforts across its extensive distribution. [ABSTRACT FROM AUTHOR]

Human-driven habitat fragmentation is increasing worldwide, and consequently many wild populations are subdivided, isolated and reduced in size. These changes in population structure reduce dispersal among subpopulations, limiting gene flow, accelerating genetic differentiation, and reducing genetic diversity and effective population sizes. Habitat fragmentation is associated with a reduced ability for populations and species to respond to changing environments, exacerbating extinction risks. The Atlantic-Gaspésie population of woodland caribou (Rangifer tarandus caribou) is isolated and genetically differentiated from other populations in Canada. It has been declining dramatically during the last century and is now considered Endangered. From a management perspective, this population is considered as a single unit of ~ 80 individuals, but GPS telemetry suggests that three subgroups use separate geographical areas and show limited dispersal. In this study, we used 16 microsatellite loci to (1) quantify and compare the genetic diversity observed within the three subgroups of the Atlantic-Gaspésie population, (2) evaluate the extent of the spatiotemporal genetic substructure among them by assessing whether the fine-scale genetic structure differs between subgroups and if it has changed over 15 years, and (3) estimate their effective population size. We found no change in genetic diversity among/within subgroups over time. We detected genetic substructure among subgroups based on their geographical locations (Logan-Albert vs. McGerrigle) and found evidence that this substructure has increased in recent years. The effective population size of this population appears to have declined by 53% over the last 15 years and is now estimated at Ne = 16 individuals. Management plans and conservation actions should consider this spatial genetic substructure to prevent further decline of this endangered population. [ABSTRACT FROM AUTHOR]

Adaptive management is a powerful means of learning about complex ecosystems, but is rarely used for recovering endangered species. Here, we demonstrate how it can benefit woodland caribou, which became the first large mammal extirpated from the contiguous United States in recent history. The continental scale of forest alteration and extended time needed for forest recovery means that relying only on habitat protection and restoration will likely fail. Therefore, population management is also needed as an emergency measure to avoid further extirpation. Reductions of predators and overabundant prey, translocations, and creating safe havens have been applied in a design covering >90,000 km². Combinations of treatments that increased multiple vital rates produced the highest population growth. Moreover, the degree of ecosystem alteration did not influence this pattern. By coordinating recovery involving scientists, governments, and First Nations, treatments were applied across vast scales to benefit this iconic species. [ABSTRACT FROM AUTHOR]

Highlights • There is variability in the abundance of terrestrial lichen following wildfire. • Forest stand characteristics are the most influential predictors of lichen volume. • Stand age is influential, but not a significant predictor of lichen abundance. • Some recent burns may have enough biomass to support foraging by caribou. Abstract Forest fires are the most dominant natural disturbance process influencing the habitat and distribution of woodland caribou (Rangifer tarandus caribou) in winter. This is a function of terrestrial lichens, the primary winter forage of caribou, taking decades to recover following fire. Working across the range of the Klaza caribou herd in the west-central Yukon, Canada, we used statistical count models to evaluate variation in lichen volume and percent cover among burns of different age classes. Burns of the same age had considerable variation in lichen abundance. Forage lichens were more abundant in coniferous stands with greater canopy openness, tree height, and basal area. Although not a significant parameter in models of volume or percent cover of lichen, time since burn improved model performance. Relative to thresholds in the published literature, most stands had sufficient lichen at 50 years post fire to be considered winter range for caribou. The relationship between caribou and burned landscapes is complex suggesting that wildlife and forest managers should look beyond burn age when accounting for the effects of fire on the availability and quality of winter habitat for woodland caribou. [ABSTRACT FROM AUTHOR]

Abstract Unspoiled wildlands of boreal landscapes provide critical habitats for wildlife. With the increase in resource development across Canada's boreal zone, woodland caribou (Rangifer tarandus caribou) and grizzly bears (Ursus arctos) are at risk of population declines. We used 4 planning scenarios with variants of these in decision-support software Marxan to allocate potential conservation priority areas for caribou and grizzly bears in boreal wildlands of the Muskwa-Kechika Management Area in northeast British Columbia, Canada. For caribou and grizzly bears across their seasonal habitats, priority areas allocated to preserve connectivity of habitat patches maintained more intact high-value habitats, with moderate opportunity cost for resource development, than those allocated under other scenarios. In winter when high-value habitats of caribou tend to coincide with resource-rich areas, priority areas allocated to preserve areas that are more vulnerable to development maintained more intact high-value habitats with higher opportunity cost (therefore greater adverse economic consequences) than those allocated in areas with lower resource potential. In growing-season (non-winter) habitats of caribou and grizzly bears, allocating priority areas toward either more vulnerable or less vulnerable areas did not substantially affect patch and landscape characteristics of conserved habitats. Priority areas intended to avoid predation risk for caribou were not effective in maintaining intact high-value habitats for caribou in these undeveloped wildlands. Conserving connectivity would best maintain most intact habitats for both species across seasons; conserving habitats most vulnerable to development also would discourage future development outside of the conserved areas in winter habitats of caribou. Findings from these conservation planning scenarios have implications globally to other areas where sensitive species are threatened by pending resource developments. Highlights • Maintain connectivity to preserve high-value habitats of caribou and grizzly bears. • Avoiding predation risk does not always maintain intact habitat for caribou. • Conserving most vulnerable winter caribou habitat helps ensure spatial integrity. • Conservation priority areas may necessitate lost opportunities for resource development. [ABSTRACT FROM AUTHOR]

Isolation by distance (IBD) is a natural pattern not readily incorporated into theoretical models nor traditional metrics for differentiating populations, although clinal genetic differentiation can be characteristic of many wildlife species. Landscape features can also drive population structure additive to baseline IBD resulting in differentiation through isolation‐by‐resistance (IBR). We assessed the population genetic structure of boreal caribou across western Canada using nonspatial (STRUCTURE) and spatial (MEMGENE) clustering methods and investigated the relative contribution of IBD and IBR on genetic variation of 1,221 boreal caribou multilocus genotypes across western Canada. We further introduced a novel approach to compare the partitioning of individuals into management units (MU) and assessed levels of genetic connectivity under different MU scenarios. STRUCTURE delineated five genetic clusters while MEMGENE identified finer‐scale differentiation across the study area. IBD was significant and did not differ for males and females both across and among detected genetic clusters. MEMGENE landscape analysis further quantified the proportion of genetic variation contributed by IBD and IBR patterns, allowing for the relative importance of spatial drivers, including roads, water bodies, and wildfires, to be assessed and incorporated into the characterization of population structure for the delineation of MUs. Local population units, as currently delineated in the boreal caribou recovery strategy, do not capture the genetic variation and connectivity of the ecotype across the study area. Here, we provide the tools to assess fine‐scale spatial patterns of genetic variation, partition drivers of genetic variation, and evaluate the best management options for maintaining genetic connectivity. Our approach is highly relevant to vagile wildlife species that are of management and conservation concern and demonstrate varying degrees of IBD and IBR with clinal spatial genetic structure that challenges the delineation of discrete population boundaries. Isolation by distance (IBD) is a natural pattern not readily incorporated into theoretical models nor traditional metrics for differentiating populations, although clinal genetic differentiation can be characteristic of many wildlife species. Landscape features can also drive population structure additive to baseline IBD resulting in differentiation through isolation‐by‐resistance (IBR). We assessed fine‐scale spatial genetic variation in boreal caribou (Rangifer tarandus caribou) and investigated the relative contribution of IBD and IBR to characterize population structure, partition spatial drivers, and evaluate the best management options for maintaining genetic connectivity across the landscape. [ABSTRACT FROM AUTHOR]

Helicopter- and snowcat-supported backcountry skiing is a unique industry that is widespread throughout southern mountain caribou habitat in British Columbia (BC). We analyzed records of helicopter and skier encounters with caribou collected by tourism operators under an agreement between the BC government and HeliCat Canada. Average reported encounter rates were low for helicopters (0.6%) and skiing groups (0.1%); however, encounters were likely underreported due to factors that affect caribou sightability. Helicopters encountered caribou more frequently than skiing groups, caribou were detected from helicopters at greater distances than by skiers. We used Bayesian network models to assess the independent contribution of different factors to the behavioural response of caribou to encounters. Encounter distance was the most important factor in both helicopter and skiing models. Larger groups of caribou responded strongly to skiers but not to helicopters, although the independent effect of this factor was small in both models. Larger helicopters elicited stronger reactions from caribou than smaller machines and were responsible for 25% of the modelled variation in caribou response. Encounters with helicopters at distances of 100-500m had a 78% probability of eliciting a concerned-to-very-alarmed response from caribou, while skiers at a similar distance had a 60% probability of eliciting the same response. The probability of concerned-to-very-alarmed responses dropped to <20% at encounter distances of >1000 m. These results indicate that initial encounter distance is the key variable to manage risk to caribou of helicopter and skiing encounters. Ongoing feedback on the effectiveness of management practices is critical to ensure the continued viability of industries operating in caribou habitat. [ABSTRACT FROM AUTHOR]