This species is common over a wide area of south-eastern Australia. One subspecies is also found on the north-eastern cosat (Strahan 1995).

Biogeographic Regions: australian (Native )

Head and body length of this species ranges from 122mm to 197mm and the tail length is an additional 56-147mm. Rattus lutreolus is dark gray or gray brown on its dorsal surfaces and cream to brown on its ventral surface. The fur on the upper half of the body is golden-tipped. Its ears are small and nearly concealed by hair. The tail is dark gray, scaly and sparsely haired (Strahan 1995).

Average mass: 115 g.

Average basal metabolic rate: 0.353 W.

• Terrestrial

Rattus lutreolus prefers poorly drained habitats, heathland, and sedges. This species has also been found on dry ridges in open forest. Density of vegetation seems to be the most important requirement of this species. This is most likely a result of selection for evasion of avian predators, or perhaps because food is more abundant in dense habitats. Habitat selection by females is most likey related to the amount of energy required for reproduction. Members of this species can survive without free water (Haering and Fox 1995, Monamy 1995, Strahan 1995).

Terrestrial Biomes: savanna or grassland ; forest

Stems and leaves are the main foods eaten by R. lutreolus. In spring and early summer, their diet expands to include seeds, fleshy fruits, and insects. Roots and underground fungi are also consumed by R. lutreolus (Cheal 1987, Norton 1987).

Typical lifespan

Status: captivity: 1 (high) years.

Range lifespan

Status: wild: 2.4 (high) years.

The breeding season is generally from early spring to autumn, but breeding can occur throughout the year. The gestation period is three weeks and the female gives birth to three to five young, each weighing approximately 5 grams. A female may produce several litters in a year and a three month old female from an early spring litter may be reproductively active that same year. Females are usually aggressive toward males except during mating (Monamy 1995, Strahan 1995).

Average birth mass: 4.87 g.

Average gestation period: 27 days.

Average number of offspring: 5.

Average age at sexual or reproductive maturity (female)

Sex: female: 79 days.

Rattus lutreolus is common throughout its limited range. Most of its original habitat has now been farmed and made unsuitable for this species (Strahan 1995).

IUCN Red List of Threatened Species: least concern

The swamp rat was hunted by Aborigines prior to European settlement and provided a significant source of meat;however, this hunting pressure no longer exists (Strahan 1995).