The swamp rat is a native Australian mammal. It won't get into your roof and chew your electric wiring. It prefers constructing tunnels and runways in long grass and dense vegetation. It won't get into garbage bins. It prefer chewing on the fresh basal stems of sedges and grasses and seeds, fruit and fungi. It lives about a year. We have what seems like a metropolis of them in amongst the lomandra that we've planted along the slope down to the river bank. The lomandra was planted originally to stabilise the bank and protect it from flooding. We hardly ever see them but there is ample evidence of their habitation in the form of tunnels. This is the closest we've gotten to photographing one:
They're cute little buggers. The photo below wasn't taken by us but we've included it to show you what a photo of one would look like if we were lucky enough to get one out in the open and sitting still for longer than 2 seconds.