ECHOLOCATION ECOLOGY AND FLIGHT MORPHOLOGY OF INSECTIVOROUS BATS (CHIROPTERA) IN SOUTH-WESTERN AUSTRALIA

A small community of obligate insectivorous microchiropterans in the Perup forest reserve of southwestern Australia was sampled to determine species flight morphologies, diets and echolocation call designs. The aspect ratio:wing loading relationships of the seven species analysed indicate a loose clustering of species into closed, edge and open microhabitats with substantial interspecific overlap. Non-parametric correlations of the bats' aspect ratios and wing loadings with their echolocation call characteristics support these foraging zone classifications. Diet analyses indicate that this community of bats forages on a wide variety of insects, although certain preferences for Lepidoptera, Hymenoptera and Coleoptera were noted. We use these results and observations of the same species from other sites to propose a microhabitat separation for the bats of the Perup forest.