Planning for carnivore recolonization by mapping sex-specific landscape connectivity

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Identifying and preserving landscape connectivity as well as planning for conflict mitigation are key for facilitating species persistence, especially in increasingly human-dominated landscapes outside of protected areas. Black bears (Ursus americanus) have lost more than a third of their former range throughout North America, but are currently recovering and recolonizing numerous human-modified landscapes. Based on previously developed sex-specific landscape suitability models, we characterized landscape use and connectivity for a recolonizing population. Since female and male carnivores differ in traits such as body size, reproductive strategies, risk aversion, and movement, we developed sex-specific models to assess intra-specific differences. Core areas (patches larger than the median annual range for each sex) represented 53–58% of their predicted suitable range, suggesting a considerable amount of habitat fragmentation. Typical linkages were 31 km for females and 37 km for males, similar to commonly documented dispersal distances for black bears. Due to having more numerous and smaller core areas being connected, female linkages occupied a larger area and had a 26% overlap with male linkages, while males overlapped 65% with females. Independent verified black bear sightings overlapped 40–50% with our predicted female and male areas, and sightings of females with offspring overlapped >90% with our predicted female areas. Anthropogenic barriers with high restoration potential were 2–4 times more numerous than natural barriers. Land cover composition within linkages was similar for both sexes, with the highest proportion of agriculture (mostly pastures and grasses) in the center of the linkage network. Core areas for both sexes extended well beyond protected areas, suggesting that private landowners will play a key role in the maintenance of high quality habitat and linkages for black bears in Missouri. Successful conservation will depend on land management that preserves a variety of high-quality habitat patches and corridors, while identifying areas of potential habitat restoration, as well as targeting management in areas with anticipated increases in bear abundance and conflict.