Bat fauna of a semi-arid environment in central western Queensland, Australia

Abstract

The results from a survey of bats in semi-arid Idalia National Park, central westernQueensland, are presented, with an analysis of habitat use, species richness, seasonal activity and reproductive patterns. Fourteen species were recorded: one megachiropteran, and thirteen microchiropterans in eight genera and three families. Significant range extensions were recorded for Vespadelus vulturnus, V. finlaysoni and Nyctophilus gouldi. Capture success using harp traps was unusually high, with 859 bats of nine species captured in 27 trap-nights (31.4 bats per trap-night). Two species (Chalinolobus gouldii and Scotorepens greyii) comprised almost 75% of all captures in harp traps. The remaining five species were recorded by means of echolocation call detection, cave searches and incidental observations. Bat species richness, abundance and capture success was greatest in riparian woodland and open forest adjacent to water; over 97% of captures in harp traps occurred at these sites. Breeding in most species appears to follow a seasonally monoestrous pattern with the ovarian and spermatogenic cycles being asynchronous. Sex ratios were close to parity but with a slightly higher proportion of females in some species in autumn. Females were generally larger and heavier than males.