This paper explores the question of why the endangered Spotted-tailed Quoll Dasyurus maculatus remains abundant in parts of north-eastern New South Wales, while populations in many other areas have declined or disappeared. Based on a two-year field study of a high-density population, we discuss a number of possible explanations for this pattern. These include high availability of prey (in particular, arboreal mammals), quality and spatial extent of habitat, low density of competitors, and relatively small home range sizes of females compared to those in other areas.
We emphasise the importance of maintaining high densities of hollow-bearing trees, which probably help to support prey populations. Managers should also seek to maintain an abundance of fallen timber, which provides shelter and movement pathways for quolls.
We hypothesise that the low density of foxes in our study area, along with the large expanse of relatively undisturbed habitat, most likely explains the high abundance of D. maculatus. However, experiments are required. Fox removal experiments should be conducted as a matter of highest priority, and should seek to measure the response of quolls to the removal of foxes at least at the individual level and preferably also at the population level.