Torpor and thermal energetics in Australian arid zone bats

Abstract

In spite of challenging and unpredictable environmental conditions, bats are among the most successful groups of Australian arid zone mammals. Yet knowledge about the thermal biology and energetics of desert bats is scarce. I used temperature-telemetry to obtain data on the thermal physiology, torpor patterns, thermoregulatory behaviour, foraging activity and roosting ecology of desert bats under natural conditions in relation to climate and season. The study species were the inland freetail bat ('Mormopterus species' 3, body mass, BM, 9 g, henceforth 'Mormopterus'), the little broad-nosed bat ('Scotorepens greyii', BM 6 g) and the inland broad-nosed bat ('Scotorepens balstoni', BM 9 g). The study was conducted at Sturt National Park (New South Wales, Australia) over three summers (2010-13), two winters (2011-12) and one spring (2011). In addition, I used flow-through respirometry to collect data on the thermal, metabolic and hygric physiology of 'Mormopterus' and 'S. greyii' over air temperatures (Ta) from 5 to 42°C during summer 2013.