Source populations and roads affect American black bear recolonization

Abstract

Understanding species distributions and population responses to environmental parameters is important for addressing landscape-level species conservation. We assessed American black bear (Ursus americanus) resource selection based on spatial distribution of a recolonizing population in Mississippi, USA. Given the philopatric behavior of female bears and the risk-disturbance hypothesis, we predicted that bears recolonizing Mississippi would occupy areas close to their source population but avoid areas near roads and with greater human population density. Using location data from radio-collared black bears, landscape metrics, and spatial autoregressive modeling, we estimated annual population-level space use. Our results confirm that black bears recolonizing Mississippi occupy habitats proximate to source populations and avoid areas near roads as probability of bear use was greater in areas closer to source breeding populations and areas farther from roads. Land cover type, elevation, and human density did not influence black bear occurrence at the spatial resolution examined. The lack of avoidance to areas inhabited by humans was likely a consequence of overall low human density, legal protection afforded this species, and that proximity to source population likely has a greater effect on recolonization than avoidance of humans.