Studies of the Ground-Dwelling Mammals of Eucalypt Forests in South-Eastern New South Wales: the Effect of Environmental Variables on Distribution and Abundance.

Abstract

The distribution and abundance of ground-dwelling mammals was examined in 13 areas within 500 000 ha of eucalypt (Eucalyptus) forest in SE New South Wales. Data are presented on the distribution and abundance of species in relation to 3 environmental gradient types involving 9 variables: 2 direct gradients (temperature, rainfall); 6 indirect gradients (aspect, steepness of slope, position on slope, landform profile around the site, altitude, season) and a resource gradient (lithology). Many species of ground-dwelling mammal of the forests of SE New South Wales were present along all gradients examined, although wide variation in abundance occurred for some species. Eight species were correlated with direct gradients and all species were correlated with at least one indirect gradient. There was wide variation and species diversity with lithology, but the variation was not related to nutrient status. Although variations in abundance occurred along environmental gradients, the composition of the ground-dwelling mammal fauna in SE New South Wales forests changed little. A fourth gradient type, the substrate gradient (biomass of plants), had the greatest effect, because in the short-term disturbances such as logging and fire play an important role. Disturbance can have a profound influence on the substrate gradient, but no influence on environmental gradients. The results are discussed in relation to the arboreal mammals and avifauna in the region and Environmental and Fauna Impact studies and forest management.