Landscape features associated with the roosting habitat of Indiana bats and northern long-eared bats

Bat conservation in the eastern United States faces threats from white nose syndrome, wind energy, and fragmentation of habitat. To mitigate population declines, the habitat requirements of species of concern must be established. Assessments that predict habitat quality based upon landscape features can aid species management over large areas. Roosts are critical habitat for many bat species including the endangered Indiana bat (Myotis sodalis) and the threatened northern long-eared bat (M. septentrionalis). While much is known about the microhabitat requirements of roosts, translating such knowledge into landscape-level management is difficult. Our goal was to determine the landscape-scale environmental variables necessary to predict roost occupancy for both species. Using MaxLike, a presence-only occupancy modeling approach, with known roost sites, we identified factors associated with roosting habitat. Spatially independent roost locations were particularly limited for northern long-eared bats resulting in differences in study areas and sample sizes between the two species. Occupancy of Indiana bat roosts was greatest in areas with > 80 % local forest cover within broader landscapes (1 km) with < 40 % forest, < 1 km of perennial streams but > 1 km from intermittent streams and in areas with poor foraging habitat. Northern long-eared roost occupancy was greatest in areas with > 80 % regional but fragmented forest cover with greater forest edge approximately 4 km from the nearest major road. Landscape features associated with roost occupancy differed greatly between species suggesting disparate roosting needs at the landscape scale, which may require independent management of roost habitat for each species.