Selection of day roosts by red bats in mixed mesophytic forests

Limited information exists on the choice of day roosts by red bats (Lasiurus borealis) in mature deciduous forests. We radiotracked 10 adult female and 4 adult male red bats as they used 44 day roosts in mixed mesophytic forests in eastern Kentucky during May through August 1996-97. On average (x̄ ± SE), bats roosted 16.5 ± 0.3 m above ground in the outer foliage of the canopy of 13 different species of hardwood trees; no conifer or snag was used as a day roost. Roost trees were dominant and codominant trees averaging 40.8 ± 1.9 cm dbh. Most roost trees (77.3%) were on ridge tops of upland forests. Each bat used an average of 3.1 roost trees and switched roost trees every 2.3 days in an area <40 m^-2. Day roosts were 277 ± 30 m from forest edge, with no roost located <50 m from any edge. These data indicate that choice of day roosts by red bats inhabiting tracts of mature contiguous forest differs from those in fragmented habitats.