The effects of drought on fish and macroinvertebrate communities in Australia have been widely described. However we have little information on the potential impacts on the iconic platypus. Here, we determined the trophic relationships of platypus populations at the Tarago River and Labertouche Creek, Victoria in two years; during drought (2009) and post drought (2013). Trophic relationships were determined by stable isotope analysis of platypus fur and potential dietary items. Stable isotope analysis, in conjunction with the conventional cheek pouch content analysis, can provide considerable information on platypus diet, including elucidating links to soft-bodied taxa such as larval dipterans which are not easily observed in cheek pouch contents.
Platypus appear to be feeding on a wide range of invertebrates and relying on terrestrial carbon inputs as the basal carbon resource supporting their food web under both drought and post drought conditions. These results highlight the generalist nature of their diet and their ability to persist in less than ideal conditions. Future challenges such as loss or limitation of habitat, especially through climatic drying, will be a major concern for the platypus and its prey.