What is the name of a large water rat? - briefly
The large water rat is the Australian water rat, commonly called the rakali (Hydromys chrysogaster).
What is the name of a large water rat? - in detail
The animal commonly referred to as a large water rat is the giant water rat, scientifically named Hydromys chrysogaster. It belongs to the family Muridae, subfamily Murinae, and is native to northern Australia and southern New Guinea.
This species exhibits a streamlined body, dense waterproof fur, and a partially webbed hind foot that facilitates strong swimming. Adult individuals reach head‑body lengths of 30–40 cm, with tails extending an additional 30–45 cm, making them the biggest members of the genus Hydromys. Body mass typically ranges from 400 g to 1 kg.
Habitat preferences include fast‑flowing streams, rivers, and coastal mangroves where rocky banks provide shelter. The giant water rat is nocturnal, emerging from burrows to hunt aquatic prey such as fish, crustaceans, amphibians, and insects. Its diet is complemented by occasional consumption of small vertebrates and plant material.
Reproduction follows a seasonal pattern; females give birth to litters of two to four young after a gestation period of approximately 35 days. Offspring are weaned within six weeks and become independent by three months.
Conservation status is listed as Least Concern by the IUCN, owing to a relatively wide distribution and stable populations. Threats include habitat degradation from water pollution, dam construction, and introduced predators such as feral cats. Monitoring programs focus on water quality assessments and protection of riparian zones to sustain viable populations.