Indiana Bat (Myotis sodalis) Day Roost Selection in the Southeastern Ontario Lake Plain of New York State

Abstract

Available habitat for the endangered Indiana bat (Myotis sodalis) varies widely across the species’ broad range and the species’ degree of habitat use specificity is not known; therefore, it is necessary to characterize the species’ habitat use patterns regionally to provide suitable guidelines for wildlife managers to conserve the species throughout its range. Understanding day roost characteristics is particularly important because habitat suitability for Indiana bats is thought to be based on the availability of suitable day roost structures. Despite having been extensively studied at the core of their range, few studies of Indiana bat day roost characteristics have been published from the northeast periphery of the species’ range, and no studies have been published from central New York State, where populations have been in steep decline due to White-Nose Syndrome since 2006. I studied day roosts of 20 female and 7 male Indiana bats in the Ontario Lake Plain northwest of Syracuse, New York, USA during the spring of 2006 and summers of 2007 and 2008 and identified 96 individual Indiana bat roost trees. Indiana bats roosted in 10 species of trees, of which Carya ovata, Acer spp., and Ulmus americana were most frequent. The mean diameter of roost trees was 41.55 ± 7.53 cm, which was similar to roost trees in other regions, but larger than the mean diameter of available trees in the same stands used by roosting Indiana bats. Male and female bats used similarly sized trees. I conclude that size of roost trees in central New York are similar to those throughout the Indiana bat’s range, that the most frequently selected tree species differ regionally, and that patterns of male versus female roost selection varies regionally. This study provides regionally specific quantitative and qualitative metrics by which managers can identify potential Indiana bat habitat for land use planning and conservation.