Endagered Species Classification
Australia's unique native rodents evolved in response to distinctive Australian ecosystems.
Australian rodents range in size from the 8g Delicate Mouse (Pseudomys delicatulus) to the Water Rat (Hydromys chrysogaster) that can weigh more than a kilogram. Native Mice usually don't live near people: if you see a small mouse near your house it’s almost certainly an introduced house mouse. Most Australian rodents have pregnancies that last one month or more, and generally give birth to up to four young. That means that they can breed fast, but not nearly as fast as introduced house mice or rats that have up to eight or more young at a time and pregnancy of only 22 days or so.
Some of our fascinating rodents include:
*The four species of Pebble-mound Mice found in northern Australia are the only mammals in the world to pile up small stones in and around their nesting burrows. Mounds weigh thousands of times the weight of the mice (which weigh about 12-14g), and can contain many thousands of pebbles.
*Water Rats (Hydromys chrysogaster) have small ears and webbed feet to help them with their aquatic lifestyle hunting yabbies. They also have a very fine, dense fur, which was once the basis for a fur trade in Australia.
*The 800g Giant White-tailed Rat (Uromys caudimaculatus) sometimes wreaks havoc in north Queensland rainforest homes, and can eat easily through coconut shell, as well as window frames.
*Several rodents were important sources of foods for aboriginal people. Stick-nest Rats, which built large woven nests of sticks, were often caught by setting their nests alight. Since Europeans colonised Australia stick-nest rats became extinct on the mainland, but their nests remain. Bits of plant material and pollen caught in remains of old stick nests have allowed some researchers to study habitats from thousands of years ago.
*The Long-haired Rat (Rattus villosissimus) is usually rare, but during good years in western Queensland numbers can build into millions and millions. The Letter Wing Kite, a usually rare bird of prey, takes full advantage of the abundance of prey, and its numbers are sustained solely on the basis of rat numbers. The world’s most venomous snake, the Inland Taipan, is another species that eagerly exploits the periodic abundance of the rats.
*The False Water Rat (Xeromys myoides) builds houses of mud in mangrove swamps for protection against high tides. At low tide it stalks the mud flats in search of crabs.
*The Spinifex Hopping Mouse (Notomys alexis) is one of the few native mammals that has been widely kept as a pet in Australia.
*The Smoky Mouse (Pseudomys fumeus) is unusual among the world’s rodents because it nests and breeds on the ground in temperate forests instead of burrowing. Interestingly the smoky mouse will elevate and undulate its tail when it becomes irritated.
*The New Holland Mouse (Pseudomys novaehollandiae) was thought to be extinct at the beginning of the 20th century. It was only rediscovered in 1967 near Sydney. Since then it has been found in several locations across NSW, Victoria and Tasmania.
*Most Australian rodents live in ecosystems that were naturally home to multiple species of rodent. An interesting example of how the species maintain a balance is seen in the coexistence of the Eastern Chestnut Mouse (Pseudomys gracilicaudatus) and the Swamp Rat (Rattus lutreolus). The Eastern Chestnut Mouse prefers vegetation that is regenerating after a fire. Its population size declines as the vegetation matures. Whereas the Swamp Rat prefers mature vegetation and its population is at its biggest when the vegetation is mature.
At least eight species of Australia’s native rodent have gone extinct in the last 200 years.
“The reason these mice disappeared is simple. The main culprits are foxes and cats. Predators can have disastrous effects on populations of small rodent, especially these Australian species. Why? Because foxes and cats can kill them faster than they can reproduce themselves.”
- Dr Fred Ford, Australian native rodent expert.
Help FAME save Australia’s unique rodents: make a donation to the Saving Threatened Australian Rodents project today.
Last updated October 2016