Occupancy patterns of the introduced, predatory sugar glider in Tasmanian forests

Introduced mammals pose serious threats to native island fauna, and understanding their distributionis fundamental to evaluating their conservation impact. Introduced sugar gliders (Petaurus breviceps) are the mainpredator of critically endangered swift parrots (Lathamus discolor) on mainland Tasmania. We surveyed sugar gli-der occurrence over~800 km2in an important swift parrot breeding area, the Southern Forests. During 4–5 vis-its per site, we used call broadcast of predatory owls to elicit sugar glider alarm calls and surveyed 100 sitesduring February/March 2016. Na€ıve occupancy by sugar gliders was high (0.79), as was detectability(0.520.03 SE), resulting in a cumulative detection probability of effectively 1. Occupancy modelling indicateda positive effect of the proportion of mature forest cover on occupancy. The best model, based on AIC scores,included the proportion of mature forest cover within a 500 m radius with constant detectability. Our studyrevealed surprisingly high rat...