Small mammal communities in Australian temperate heathlands and forests.

Abstract

Temperate heathlands and forests in Australia are largely restricted to the eastern, southern and south-western coastal margins. Although a small macropodid may be included in some forests the small-mammal assemblages are commonly species from only two metatherian families, bandicoots and dasyurids, and one eutherian family, murid rodents. These native rodents divide into 'old endemics' (Pseudomys, Mastacomys and Melomys) and 'new endemics' (Rattus). Introduced species fill the niches of absent natives rather than 'new' niches, implying few unused resources in these communities. The basic community has one species of Rattus, one dasyurid and one bandicoot and usually one 'old endemic'; additional species from each group are added when greater resources are available. Abundance is low overall, and may reflect reduced productivity; species richness and diversity are usually greater in heathland, but densities are greater in forests and may result from the lower nutrient levels in heathlands. There is a negative correlation between species diversity and latitude, although species diversity depends more on local variables such as habitat diversity. Tasmania has a less diverse fauna, but this may be an island effect as the abundance is generally increased.