Australian Mammalogy Australian Mammalogy Society
Journal of the Australian Mammal Society

Estimating western ringtail possum (Pseudocheirus occidentalis) density using distance sampling

G. R. Finlayson A B E , A. N. Diment B , P. Mitrovski A , G. G. Thompson C D and S. A. Thompson A D
+ Author Affiliations
- Author Affiliations

A Coffey Environments, Suite 2, 53 Burswood Road, Burswood, WA 6100, Australia.

B Institute of Wildlife Research, School of Biological Sciences, University of Sydney, NSW 2006, Australia.

C Centre for Ecosystem Management, Edith Cowan University, Joondalup Drive, Joondalup, WA 6027, Australia.

D Terrestrial Ecosystems, 10 Houston Place, Mount Claremont, WA 6010, Australia.

E Corresponding author. Email:

Australian Mammalogy 32(2) 197-200
Submitted: 14 December 2009  Accepted: 16 March 2010   Published: 15 September 2010


A reliable estimate of population size is of paramount importance for making management decisions on species of conservation significance that may be impacted during development. The western ringtail possum (Pseudocheirus occidentalis) is regularly encountered during urban development and is the subject of numerous surveys to estimate its abundance. A variety of techniques have been used for this species with mixed results. This paper reports on a case study using distance sampling to estimate density of P. occidentalis in a small habitat remnant near Busselton, Western Australia. Density estimates obtained were within the range of previous studies of this species and we suggest that this technique should be employed in future surveys to improve the accuracy of population estimates for this species before development.


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