ROOSTING AND FORAGING ECOLOGY OF THE QUEENSLAND BLOSSOM BAT (SYCONYCTERIS-AUSTRALIS) IN NORTH-EASTERN NEW-SOUTH-WALES - FLEXIBILITY IN RESPONSE TO SEASONAL-VARIATION

Radiotelemetry was used to track blossom bats (Syconycteris australis) at Iluka and Harrington in northern New South Wales. A total of 31 ba ts was tracked to 110 roosts. Bats foraged on nectar and pollen in Ban ksia integrifolia heathland, but roosted 50-4000 m away in littoral ra inforest. Bats showed a strong fidelity to their feeding area (about 1 3 ha), returning to their original capture point each night and spendi ng a large proportion of their foraging time there. After leaving thei r roost, adults spent, on average, 45% of their time active and remain ed in heathland throughout the night. All age-sex classes roosted soli tarily during the day amongst rainforest foliage, usually in the subca nopy layer. Most roosts were occupied for one day only and adults were more roost-mobile than juveniles. Mean movements between roosts were greater at Harrington (125 m), where the rainforest is fragmented, tha n at Iluka (42 m), where rainforest is intact. Bats shifted their roos ts seasonally, from the rain-forest edge in winter to the rainforest i nterior in spring/autumn. This behaviour allows for avoidance of cold temperatures inside the forest in winter and of hot temperatures of th e forest exterior in spring/autumn. A further possible response to the seasonal climate prevailing at the study area was a reduction in the commuting distance (from roosts to feeding areas) from autumn/spring ( 1.4 km) to winter (0.8 km). Such flexible roosting and foraging strate gies may be effective in allowing S. australis to exploit subtropical and temperate areas of Australia.