Summer ecology of Indiana bats in Ohio

The Indiana bat (Myotis sodalis) is a tree roosting species found throughout the eastern United States that is federally listed as endangered by the U.S. Fish and Wildlife Service. A more detailed understanding of summer roosting and foraging habitat for Indiana bats is needed for effective conservation and management. The objectives of this research included identifying and describing aspects of the summer ecology of this species, especially selection of tree roosts and foraging habitat in the Big Darby Creek area in Ohio. During the 2008-2010 seasons, we captured 55 Indiana bats and radiotracked 51 individuals. We tracked bats to 56 roost trees 474 times (bat roost days). Roosts were largely clustered in riparian woodland habitat along the Big Darby Creek. Roost trees were of 11 different species but two of the trees could not be identified. Eight of the trees were alive, two were declining, and the rest were dead or in a greater stage of decay. Roost trees were found relatively close to water, and tended to be dead or decaying, a high percentage of loose bark, and a dominant canopy class, when compared to other available trees. We calculated 33 home ranges. Average home range size was 210.5 ± 130.6 SD ha (0.84 ± 0.52 SD mi2) for fixed kernel and 374.2 ± 359.6 SD ha (1.49 ± 1.44 SD mi2) for minimum convex polygon. Bats selected for woodland and water habitats, and avoided cropland at multiple spatial scales. Although most foraging flights occurred within the riparian corridor, bats also moved outside the corridor to upland areas.