Ecology and population biology of long-nosed bandicoots (Perameles nasuta) at North Head, Sydney Harbour National Park

Abstract

The population biology, habitat utilisation and diet of a small, isolated population of long-nosed bandicoots (Perameles nasuta) was studied over a 22-month period at North Head in Sydney Harbour National Park, New South Wales. Reproductive output in this urban environment was high, with a mean litter size of 2.3 and production of up to four litters per year. The peak of reproductive activity was in late spring and early summer, with a cessation of breeding in late autumn or early winter. The main causes of death were identified as road trauma (58% – probably an overestimate because of the ease of finding road deaths) and predation by cats and foxes (37% – probably an underestimate because of the difficulty of locating carcasses unless radio-collared). Bandicoots utilised all macrohabitats (open grassed areas, heath, forest, swamp and scrub), but extensively used open grassed areas for foraging. Males had larger home ranges (4.4 ± 0.8 ha) than females (1.7 ± 0.2 ha). The largest home ranges of males coincided with the peak of the breeding season (September–November). Throughout the year P. nasuta fed primarily on beetles, invertebrate larvae and ants, but also on other invertebrates and on plant and fungal material. Some vertebrate and human- derived material (birdseed, vegetable scraps, plastic, twine) was also eaten. Although remarkably adaptable in its reproductive and dietary strategies, this population of long-nosed bandicoots is likely to follow other urban bandicoot populations toward extinction unless there is active management to reduce the high rate of mortality from motor vehicles and introduced predators.