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Wolverines ( Gulo gulo ) are a circumboreal species that has experienced substantial range reduction worldwide. In Canada, the wolverine has been extirpated entirely from the east, and from prairie regions in the west. The province of Alberta holds the south-central portion of wolverines' Canadian range, and there they have been designated as Data Deficient since 2001 due to a historical lack of information. Our aim was to provide a first approximation of a wolverine abundance estimate at the provincial scale to inform science-based management as well as status designation. We synthesised existing density estimates and wolverine-habitat relationships to create a province-wide density estimate for wolverines. Densities were derived from five landscapes, spanning protected National Parks in the Rocky Mountains, the highly developed Foothills and the northcentral and northwestern boreal forests. Densities were estimated using spatially explicit capture-recapture (SECR) models. Densities ranged from 6.74 wolverines/1000 km 2 in the northwest boreal to 0.71 wolverines/1000 km 2 in the foothills. The proportion of adults was based on a study from the northwest, which estimated 57% adults to 43% subadults. Extrapolating densities across natural subregions (bioclimatic ecoregions), based on known habitat relationships, it was estimated that there were 955 wolverines in the province, of which 544 were adults. This number falls well below an IUCN threshold for a legally listed species; we suggest a reassessment of the wolverine status in Alberta and considering commensurate conservation actions., Competing Interests: The authors declare no conflicts of interest., (© 2024 The Author(s). Ecology and Evolution published by John Wiley & Sons Ltd.)

Contemporary landscapes are subject to a multitude of human-derived stressors. Effects of such stressors are increasingly realized by population declines and large-scale extirpation of taxa worldwide. Most notably, cumulative effects of climate and landscape change can limit species' local adaptation and dispersal capabilities, thereby reducing realized niche space and range extent. Resolving the cumulative effects of multiple stressors on species persistence is a pressing challenge in ecology, especially for declining species. For example, wolverines ( Gulo gulo L.) persist on only 40% of their historic North American range. While climate change has been shown to be a mechanism of range retractions, anthropogenic landscape disturbance has been recently implicated. We hypothesized these two interact to effect declines. We surveyed wolverine occurrence using camera trapping and genetic tagging at 104 sites at the wolverine range edge, spanning a 15,000 km 2 gradient of climate, topographic, anthropogenic, and biotic variables. We used occupancy and generalized linear models to disentangle the factors explaining wolverine distribution. Persistent spring snow pack-expected to decrease with climate change-was a significant predictor, but so was anthropogenic landscape change. Canid mesocarnivores, which we hypothesize are competitors supported by anthropogenic landscape change, had comparatively weaker effect. Wolverine population declines and range shifts likely result from climate change and landscape change operating in tandem. We contend that similar results are likely for many species and that research that simultaneously examines climate change, landscape change, and the biotic landscape is warranted. Ecology research and species conservation plans that address these interactions are more likely to meet their objectives.

Understanding a species' behavioral response to rapid environmental change is an ongoing challenge in modern conservation. Anthropogenic landscape modification, or "human footprint," is well documented as a central cause of large mammal decline and range contractions where the proximal mechanisms of decline are often contentious. Direct mortality is an obvious cause; alternatively, human-modified landscapes perceived as unsuitable by some species may contribute to shifts in space use through preferential habitat selection. A useful approach to tease these effects apart is to determine whether behaviors potentially associated with risk vary with human footprint. We hypothesized wolverine (Gulo gulo) behaviors vary with different degrees of human footprint. We quantified metrics of behavior, which we assumed to indicate risk perception, from photographic images from a large existing camera-trapping dataset collected to understand wolverine distribution in the Rocky Mountains of Alberta, Canada. We systematically deployed 164 camera sites across three study areas covering approximately 24,000 km(2), sampled monthly between December and April (2007-2013). Wolverine behavior varied markedly across the study areas. Variation in behavior decreased with increasing human footprint. Increasing human footprint may constrain potential variation in behavior, through either restricting behavioral plasticity or individual variation in areas of high human impact. We hypothesize that behavioral constraints may indicate an increase in perceived risk in human-modified landscapes. Although survival is obviously a key contributor to species population decline and range loss, behavior may also make a significant contribution.