Fragmentation of native habitat continues to threaten unique Australian species. We have little understanding of the processes leading to extinction of mammal populations in remnant habitat patches. Analysis of genetic structure amongst, and relatedness structure within, patch populations compared to populations in continuous habitat will yield vital information regarding the effect of fragmentation on population processes such as dispersal and social organisation. These data are essential for rational management of populations in the face of continued human disturbance of natural systems.
We are using genetic markers (mainly microsatellites) to examine these effects in a range of Australian native mammals representing major ecological types: arboreal gliding marsupials (greater, sugar and squirrel gliders), small mammals (Antechinus spp.) and large burrowing herbivores (wombats). The work involves firstly identifying populations that may be suffering demographic isolation through fragmentation, using a variety of approaches including GIS mapping and genetic analyses. Genetic markers are then applied to questions regarding dispersal and mating systems in these populations, along with control populations residing in continuous habitat. Differences in these parameters between fragmented and control sites can then be inferred to result from habitat fragmentation.
Various aspects of this program have been supported by grants from the Mark Mitchell Foundation, National Geographic Society, Monash Small Grants, the Australian Research Council and a variety of State wildlife agencies with whom we collaborate.
