Where are water rats found? - briefly
Water rats occupy freshwater environments—rivers, lakes, swamps, and coastal wetlands—throughout southeastern Australia, including New South Wales, Victoria, South Australia and Tasmania. Isolated populations are also recorded in New Guinea and nearby islands.
Where are water rats found? - in detail
Water rats inhabit a broad range across the Australasian region, primarily in southeastern Australia and New Zealand. In Australia they occupy the eastern and southeastern states, including New South Wales, Victoria, Tasmania, and parts of South Australia and Queensland. Their presence is most common along riverbanks, lakes, swamps, and coastal estuaries where dense vegetation provides cover and access to water.
In New Zealand the species is found throughout both the North and South Islands, favoring lowland streams, wetlands, and the margins of lakes. Populations are concentrated in the Waikato, Bay of Plenty, Canterbury, and Otago regions, where the climate supports abundant aquatic plants and invertebrate prey.
Key habitat characteristics across the range include:
- Freshwater environments with slow‑moving or still water.
- Riparian zones with thick reeds, sedges, and tussock.
- Areas offering both terrestrial shelter and easy entry to water.
Island populations extend to some offshore islands of New Zealand, such as the Chatham Islands, where introduced water rats have established stable colonies. In addition, isolated pockets exist in the highland streams of the Australian Alps, where cooler temperatures and pristine water quality sustain viable groups.
Overall, the distribution is tied to temperate climates, reliable freshwater sources, and vegetated banks that support foraging and nesting activities.