1. Division of Botany and Zoology, Australian National University, P.O. Box 4, Canberra, A.C.T. 2601
2. Division of Wildlife & Ecology, CSIRO, P.O. Box 84, Lyneham, A.C.T. 2602 (address for reprints)
3. Western Australian Wildlife Research Centre, Department of Conservation and Land Management, P.O. Box 51, Wanneroo, W.A. 6065