Water mouse

What does it look like?

The water mouse is one of Australia’s rarest native rodents. It can be distinguished from other species by its small body size, small eyes and rounded ears. The colouration of its coat is slate-grey, and the belly is white.

Where does it live?

The water mouse is found within coastal areas of central and South East Queensland, from Proserpine south to the Queensland–New South Wales border region, as well as a small number of near-coastal sites in the top end of the Northern Territory. On the Gold Coast, it has only been recorded along the Pimpama River, Coomera River and McCoys Creek.

Ecology & habitat

Across its range, the water mouse inhabits coastal saltmarsh (including samphire shrub lands), saline reed-beds and saline grasslands, mangroves, and coastal freshwater wetlands. On the Gold Coast, it has only been observed in mangroves and saltmarsh. The species’ diet consists of invertebrates including crabs, marine shellfish, and snails.

The water mouse is active at night, sheltering during the day in constructed nesting mounds and natural or artificial hollows. The species has a range of nesting strategies dependant on the vegetation community that it inhabits. To date, it has only been observed nesting in mangrove hollows on the Gold Coast.

How is its survival threatened?

• Habitat degradation due to altered hydrology
• Habitat modification from changes to soil chemistry (for example, acid sulphate soils and pesticide applications) and recreational vehicles
• Habitat loss and fragmentation for infrastructure projects and urban development
• Environmental changes or management activities (for example, mosquito control) that negatively affect foraging resources
• Predation by foxes (and possibly domestic cats)
• Habitat damage by feral pigs

How can we help?

• Improve our understanding of the species’ distribution and habitat areas across the city
• Protect existing populations and remaining habitat areas from clearing and other high impact activities
• Minimise altered hydrology in water mouse habitat
• Improve water quality by minimising habitat degradation
• Restore and/or expand habitat areas for existing populations
• Reduce mortality rates caused by predation

Image credit: Narelle Power