Extinction of Turtles in the River Murray: Consequences and Solutions.
Threats to freshwater turtles have led to global declines. These declines have been ascribed as almost entirely the result of human activities. In south-eastern Australia, three turtle species occupy the Murray River and its associated waterways; the Broad-shelled Turtle Chelodina expansa, Murray River Turtle Emydura macquarii, and the Eastern Long-necked Turtle Chelodina longicollis. The Murray River has been heavily modified, both aquatically and terrestrially, including water manipulation, habitat clearing, and the introduction of exotic animals and plants. Significant declines were recently detected in the catch per unit effort and the proportion of juveniles captured for both the Eastern Long-necked Turtle and the Murray River Turtle (when compared to data from the 1970s). These declines have been attributed to both climatic drying and turtle nest predation by the introduced Red Fox, Vulpes vulpes.
The aims of this current study are to investigate stage-specific population survivorship in the mid-Murray region, and local, landscape-scale, and historical factors that influence survivorship. To specifically investigate the impact of the introduced Red Fox, this project will evaluate whether turtle nest predation rates are a product of nesting behaviour and nest density, as well as the effectiveness of current fox control management regimes.
Dr Ricky Spencer, Professor Michael Thompson (USyd) and A/Professor Bruce Chessman (UNSW)