An exposed tree fork and a rock formation crevice as diurnal roost sites for a nocturnal hollow-retreating marsupial, the common brushtail possum ( Trichosurus vulpecula )

Abstract The common brushtail possum ( Trichosurus vulpecula ) is a nocturnal marsupial that primarily retreats to tree hollows. However, there are some reports of denning in other sites like dense foliage, rock outcrops and animal burrows. We report observations of common brushtail possums roosting in an exposed tree fork and roosting in a ground-level rock crevice in the Blue Mountains region, New South Wales, Australia. Both remained at those sites for the entire day, with the individual in the exposed tree fork waking briefly to browse. The observation of the possum in the sandstone crevice differs from previously reported instances of roosting in rock outcrops in that this crevice was at ground level and accessible to ground-based predators.