Seasonal Thermoregulation of Brush-Tailed Mulgaras (Dasycercus blythi)

In Australia's arid zone, brush-tailed mulgaras (Dasycercus blythi) occupy burrows throughout the year, use bouts of energy/water saving torpor during the winter reproductive season, but little is known about their thermoregulation outside of winter. We used temperature-telemetry to investigate the daily body temperature (Tb) fluctuations during both winter and summer. In winter, males and females readily used torpor (males = 88.0% ± 10.6% from 150 days tracked, n = 3; females = 85.4% ± 5.8% from 151 days tracked, n = 2) and in summer torpor was rare in both sexes (males = 1.6% ± 1.9%, 163 days tracked, n = 4; females = 3.0% ± 2.8%, 157 days tracked, n = 4). The minimum winter Tb was 11.7°C (mean Tb = 23.3°C ± 4.2°C males; 19.6°C ± 5.1°C females); in summer Tb did not fall below 30°C. Torpor bouts in winter lasted for 7.1 ± 6.1 h in males and 11.8 ± 7.8 h in females; in summer torpor bouts were