Commenced studies of Australian mammals at Macquarie University in 1972, investigating sex chromosome loss in bandicoots, then studied bandicoot and rock wallaby taxonomy. The latter studies led to investigations of hybrid zones between adjacent species of rock wallabies and the fertility of captive rock wallaby hybrids and also hybrids between pademelon species. Became involved in 1990 with the study of Campbelltown koalas during disputes between conservationists and developers at the site of the recently proclaimed Dharawal NP. That study, which depends on the local community reporting sightings of koalas, firstly so that we can eartag them and secondly so that we can plot their movements around the district. Also interested in the distribution of other terrestrial mammals of the Sydney basin and surrounds, particularly platypuses and water rats.