How we’re helping
The plains mouse (Pseudomys australis) was first recorded in the Arid Recovery Reserve in 2006. Plains mice numbers have increased and are now frequently recorded during trapping and spotlighting surveys. The habitat of the plains mouse has likely increased due to the release of rabbit calicivirus between 1995 and 2009.
We previously thought that plains mice needed cracking clay depressions in gibber plains to survive. However, since first being recorded in the reserve in the absence of feral cats, foxes, rabbits and livestock, the plains mouse has spread into all types of habitat, including stony swales and dunes. It is now clear that its apparent reliance on gibber plains is a refugial effect and it can occupy a variety of habitats.
Where they’re found
The plains mouse was once widespread in the arid and semi-arid regions of Australia. Since European settlement, its range has declined by 50 to 90% and it is now restricted to the gibber (stone-covered) plains of northern SA and southern NT.
The major threat to the plains mouse is habitat degradation due to trampling and grazing from cattle and sheep. Predation from feral cats and foxes have also contributed to their decline, with plains mice frequently turning up in the stomach contents of cats shot in the region. The plains mouse is now listed nationally as vulnerable.
The plains mouse builds shallow, complex burrows which are dug into cracks in the gibber plain or at the base of shrubs. In burrows dug beneath shrubs, the soil is softer and complex warrens can be built up to 2m². Nest chambers are built with dried grass. During the breeding season, burrows often contain one male and several females, while outside of breeding season burrows can be occupied by up to 20 mice. The mice leave tracks that connect their burrows and lead off to their feeding areas.
Plains mice mainly eat grass seeds, but also eat other plant material, insects and small reptiles. The plains mouse is able to survive without drinking – obtaining all its water from food.
Breeding occurs primarily after rainfall when there is an increase in food availability. As conditions deteriorate, populations can decline rapidly. Litter sizes are usually three to four, with weaning taking place 28 days after birth.