Roost caves of the Eastern Horseshoe Bat Rhinolophus megaphyllus Gray, 1834 (Chiroptera: Rhinolophidae) in the Pilliga forest in northern inland New South Wales, Australia

Seven sandstone caves in the Pilliga forest, in northern inland New South Wales, were identified as diurnal roosting sites used by the Eastern Horseshoe Bat Rhinolophus megaphyllus. The population of R. megaphyllus in the Pilliga forest is considered to be of regional conservation significance, being on the western inland edge of the species’ Australian distribution in a bioregion predominantly devoted to agriculture. Data derived from diurnal counts of roosting bats in the seven caves over the period 2007-2014 is presented here, together with a description of the caves and a review of the spatial and temporal distribution of local records of the species. Rhinolophus megaphyllus is an uncommon resident in the Pilliga forest with the core area of distribution coinciding with the most topographically rugged areas in the south-eastern and eastern parts of the forest. The roosting caves were between 10 and 30 m deep with bats generally occupying the darkest available recesses. All of the caves had either restricted entrances into or restricted dimensions within the roosting chamber. The maximum colony size noted during diurnal counts was nine bats, although observations of bats emerging at dusk indicated that under-estimation during diurnal counts was likely. Roosting R. megaphyllus were alert and active from late August to mid June and were generally inactive in July, remaining motionless with wings closely furled. Additional microchiropteran species co-habiting caves in the Pilliga forest were the Large-eared Pied Bat Chalinolobus dwyeri and Eastern Cave Bat Vespadelus troughtoni.