In the past, platypus lived in South Australia but they no longer do so. There are platypus on Kangaroo Island, but these were brought there in an attempt to save animals people thought might become extinct. There are very few if any platypus left in most the Murray-Darling Basin. The water there is no good because people used it to grow plants, and cleared the trees from the land. It is strange that the platypus does not live in some healthy rivers. It does live in some less healthy coastal rivers, for example the Maribyrnong River in Victoria. 