Diet of the Australian Freshwater Turtle Emydura krefftii (Chelonia: Chelidae), in an Unproductive Lentic Environment

The abundance of Emydura krefftii in the nutrient-deficient dune lakes of Fraser Island, Australia, is explained in terms of the species' broad food habits and its ability to directly utilise foods of terrestrial origin. Small specimens of E. krefftii are carnivorous, relying principally on aquatic and terrestrial insects, and small crustaceans. As they grow, the turtles become omnivorous and eat larger varieties of insect and crustacean. The changes in diet with increasing turtle size are explained in terms of energetic efficiency, and by the fact that as the turtles grow, more robust food items become available to them. The diets of mature males and females of similar sizes do not differ appreciably.