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Abstract
Mass mortality from white-nose syndrome (WNS) has resulted in increased conservation concerns for bats in North America and the federal listing of the northern long-eared bat (Myotis septentrionalis). To better manage M. septentrionalis in northern Georgia, which represents the southern extent of the range, we identified the species distribution and habitat associations. We used mist-netting records from 2007-2017 to develop dynamic occupancy models relating occurrence to habitat and geographic features at two spatial scales. Models estimated M. septentrionalis occupancy prior to WNS presence in the study area (2007-2011) and allowed for annual changes in occupancy through estimates of extinction and colonization. Prior to WNS, M. septentrionalis occupancy was positively associated with percent deciduous forest at the home range scale and elevation at the home range and landscape scales. Post-WNS M. septentrionalis occupancy was associated with large patches of deciduous forest and areas of higher elevation at the landscape scale, resulting in the extirpation of peripheral populations. Patterns in M. septentrionalis roosting habitat selection were assessed by comparing roosts to surrounding vegetation and topographic characteristics at two spatial scales. M. septentrionalis disproportionately roosted in snags relative to their availability and selected snags with a larger diameters. At the home range scale we observed an interactive effect of slope and aspect, with both reproductive females and all bats selecting west facing aspects on low slopes and showing no aspect preference as slope increased. In addition to mortality from WNS, millions of bats in North America have died due to collisions with wind energy facilities. However, only M. septentrionalis has received federal protection as a result of this combined mortality. To evaluate the potential for M. septentrionalis to act as an umbrella species for the bat community, we constructed a community occupancy model for species in northern Georgia. Protection was assessed based on co-occurrence with M. septentrionalis, with only the hoary bat (Aeorestes cinereus) and silver-haired bat (Lasionycteris noctivagans) found to confer adequate protection through protection of habitat for M. septentrionalis. However, a small number of species, preferably those with limited co-occurrence, likely could confer protection to the larger bat community.