Ecology of the brush-tailed mulgara Dasycercus blythi in central Western Australia

Arid Australia is home to a diverse array of marsupial predators (Dasyuridae) that play important ecological roles. We studied the population dynamics, demography, burrow use, movements, diet, and seasonal and diel activity of the brush-tailed mulgara Dasycercus blythi (hereafter ‘mulgara’) in central Western Australia, representing a south-western part of its range. Working at two properties (Matuwa and Jundee), we collected data at 20 survey sites in spinifex grasslands through pitfall trapping, radio-tracking, camera trapping and scat collection. Mulgara population density at Matuwa was 0.08 to 0.40 individuals ha−1 per session and abundance was approximately twice as high at Matuwa compared to Jundee, most likely due to long-term feral cat control. Capture rates overall were higher in autumn compared to spring, particularly for males, which had lower survival probabilities than females. Activity of mulgaras on camera traps was highest in summer and autumn and lowest in winter and spring. Mulgaras showed seasonal differences in nightly activity, with activity in the coldest months peaking just after sunset and then declining, whereas activity in the warmer months was more consistent throughout the night. The mean distance between denning burrows on consecutive days was 105 m, with males moving further and more frequently than females. Mulgara diets were dominated by invertebrates, particularly ants/termites, with vertebrates being uncommon, possibly due to multiple years of below average rainfall. Our study provides new insights into the ecology of the brush-tailed mulgara, while also adding further depth to existing knowledge of mulgara population dynamics, behaviour and diet.