Capture and handling of wildlife is often an important component of studies where detailed demographic, behavioral, physiological, or health data are required. Yet, capturing and handling wildlife is sometimes controversial and lacking public support because of concern about effects on individuals. Investigating potential effects of capturing wildlife is also important to inform data-censoring protocols when using information obtained from captured animals. We investigated the short-term effect of helicopter-based capture and handling on movements of free-ranging bison (Bison bison) that were chemically immobilized in Yukon, Canada. We examined daily movement rates, home range size, and displacement of global positioning system-collared individuals immediately after capture and for 20 days thereafter. Our results indicate that there is a minimal short-term effect of helicopter-based capture on bison movements. Significant differences from apparent pre-capture movement behavior were observed only within 24 hours after capture. We observed variation among individuals, however, with some animals taking up to 10 days to return to apparent pre-capture movement rates, whereas others had no measurable response to capture. Despite individual variation, >80% of individuals had returned to apparent pre-capture movement behavior within the first 5 days after capture. Furthermore, sex-based effects were evident: females increased their daily movement rates, home range size, and displacement after capture, whereas males had either no effect or decreased movement rates. Our results suggest that movement rates are altered for only a short period after capture and, therefore, should not have severe negative effects on bison using our protocols. Accordingly, researchers should censor the first 10 days after capture from their analyses to avoid using biased information. Our study should also help inform public discourse regarding capturing and handling wildlife for research or management purposes. Ó

Scavenging by vertebrates can have important impacts on food web stability and persistence, and can alter the distribution of nutrients throughout the landscape. However, scavenging communities have been understudied in most regions around the globe, and we lack understanding of the biotic drivers of vertebrate scavenging dynamics. In this paper, we examined how changes in prey density and carrion biomass caused by population cycles of a primary prey species, the snowshoe hare Lepus americanus, influence scavenging communities in the northern boreal forest. We further examined the impact of habitat and temperature on scavenging dynamics. We monitored the persistence time, time until first scavenger, and number of species scavenging experimentally‐placed hare carcasses over four consecutive years in the southwestern Yukon. We simultaneously monitored hare density and carrion biomass to examine their influence relative to temperature, habitat, and seasonal effects. For the primary scavengers, we developed species‐specific scavenging models to determine variation on the effects of these factors across species, and determine which species may be driving temporal patterns in the entire community. We found that the efficiency of the scavenging community was affected by hare density, with carcass persistence decreasing when snowshoe hare densities declined, mainly due to increased scavenging rates by Canada lynx Lynx canadensis. However, prey density did not influence the number of species scavenging a given carcass, suggesting prey abundance affects carrion recycling but not necessarily the number of connections in the food web. In addition, scavenging rates increased in warmer temperatures, and there were strong seasonal effects on the richness of the vertebrate scavenging community. Our results demonstrate that vertebrate scavenging communities are sensitive to changes in species’ demography and environmental change, and that future assessments of food web dynamics should consider links established through scavenging.

This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

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.

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