Abstract
Woylie or brush-tailed bettong (Bettongia pencillata) populations are undergoing a major decline in southwest Western Australia. Through collaboration with the Department of Environment and Conservation (DEC) it has been possible to examine the parasite fauna of the declining population since the decline commenced in 2006. Only two potential pathogens have been identified, Trypanosoma and Toxoplasma, which, when compared with healthy woylie populations, are associated with the decline. Although it appears unlikely that the parasites are solely responsible for the decline in woylie population size, they may predispose woylies to increased mortality. Molecular characterisation has revealed how little we know about the phylogenetic relationships and ecology of both Trypanosoma and Toxoplasma in Australian native wildlife raising questions about transmission and control. The parasitological investigation of woylies has demonstrated the value of undertaking longitudinal surveillance in natural systems using non-invasive sampling and molecular tools to characterise infectious agents in terms of wildlife health, parasite biodiversity and ecology.