Habitat use by the eastern horseshoe bat, Rhinolophus megaphyllus, in a fragmented woodland mosaic

Abstract

I examined habitat use by eastern horseshoe bats, Rhinolophus megaphyllus, in a fragmented woodland mosaic in south-east Queensland, Australia. I predicted that the species would forage within the remaining woodland remnants in the mosaic, because its flight pattern and auditory system are adapted for locating and capturing prey in cluttered habitat (i.e. close to and within vegetation). I studied habitat use by light-tagging and radio-tagging bats that roosted in a disused mine in a large woodland fragment. I observed bats within an area of 95 ha, which was composed of grassland (71% of area), woodland (14%), and edge habitat (boundary of woodland and grassland, and isolated trees in grassland – 15%). Bats foraged in woodland and edge habitat but not over grassland, and used woodland significantly more often than expected by its availability. Commuting bats left the woodland fragment in which the roost was located by one of two routes, both of which led into riparian woodland. One route was entirely within woodland, whereas the other route crossed 250 m of open ground. The study indicates that R. megaphyllus should respond negatively to the fragmentation of woodland and forest because this process will reduce the availability of its preferred foraging habitat.