Australian Mammalogy Australian Mammalogy Society
Journal of the Australian Mammal Society
RESEARCH ARTICLE

Genetic analysis reveals a distinct and highly diverse koala (Phascolarctos cinereus) population in South Gippsland, Victoria, Australia

Tristan Lee A D , Kyall R. Zenger B , Robert L. Close C and David N. Phalen A

A Wildlife Health and Conservation Centre, Faculty of Veterinary Science, The University of Sydney, NSW 2570, Australia.

B School of Marine & Tropical Biology, James Cook University, Townsville, Qld 4811, Australia.

C School of Biomedical and Health Sciences, University of Western Sydney, NSW 2560, Australia.

D Corresponding author. Email: tristan.lee@sydney.edu.au

Australian Mammalogy 34(1) 68-74 http://dx.doi.org/10.1071/AM10035
Submitted: 25 October 2010  Accepted: 19 May 11   Published: 7 November 2011

Abstract

Population genetics can reveal otherwise hidden information involving a species’ history in a given region. Koalas were thought to have been virtually exterminated from the Australian state of Victoria during the koala fur trade of the late 1800s. Koalas in the South Gippsland region of Victoria were examined using microsatellite markers to infer population structure and gene flow and to locate a possible remnant gene pool. The results indicate that the South Gippsland koala population had higher genetic diversity (A = 5.97, HO = 0.564) than other published Victorian populations, and was genetically distinct from other koala populations examined. South Gippsland koalas, therefore, may have survived the population reductions of the koala fur trade and now represent a remnant Victorian gene pool that has been largely lost from the remainder of Victoria. This paper illustrates that historic anthropogenic impacts have had little effect on reducing the genetic diversity of a population in the South Gippsland region. However, the South Gippsland population is now subject to threats such as logging and loss of habitat from housing and agriculture expansion. Our results suggest that the South Gippsland koalas require an alternative conservation management program.

Additional keywords: bottleneck, genetic diversity, microsatellite DNA, population structure, translocation.


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