The ecology of insectivorous bats in the Simpson Desert, Central Australia: Habitat use

Abstract

Seven species of insectivorous bats were positively identified within a regional study area in the Simpson Desert in south-western Queensland. This paper describes habitat use by this bat assemblage and the degree to which presence of water, food availability and roosting potential impact on bat activity. Bats predominantly utilised water sources, rock outcrops, dune/swale areas near woodland, dry creek lines and coolibah woodland habitats. However, they rarely used open habitats (open plain and dune/swale), acacia scrub and gidgee woodland. The bats foraged most often over water and on calmer nights, when insects were more active. Although highly active over water in some areas, bats may survive in the Simpson Desert without access to permanent water. Food availability in terms of flying insect abundance and biomass did not appear to significantly determine the use of different habitats. However, activity over the entire study area was concentrated in areas with a higher roosting potential. Consequently both tree and cave roost sites may be a limiting resource, resulting in bat activity being restricted predominantly to oases in the Simpson Desert study area.