Mice are just one of those things people find hard to appreciate - possibly only one step up from a rat (a small step some might say). But the native mice that were once abundant across NSW landscapes were not the smelly, wall-chewing, dropping-on-bench top kind of creature people think of when they hear the word “mouse”.
All the native species are quite closely related to introduced mice and rats (less than 10 million years of separation, small in evolutionary terms).
This means and that means many of them do look similar. However, there was a great diversity of colours, shapes and sizes out there in 1788, from the very small (15g) New Holland mouse (which does look a lot like a house mouse), to the pretty large (400g) white-footed rabbit rat and definitely large (1.5kg!) water rat.
Coupled with that variety is their importance in the ecosystem. It is likely that there is still a great deal of variety amongst rodent species.
Rodent are great consumers of plant seed and fungi, and at natural abundances were probably instrumental in keeping vegetation communities functioning properly.
Another key ecological role for rodents is being eaten. Snakes, owls and quolls have all suffered from the demise of the rodent fauna. On the inland slopes and plains most areas are devoid of any native species.
Now, however, Foundation funded research is attempting to learn about the processes necessary to recover populations of native mice and encourage them back into our national parks and reserves.
This requires and understanding of whether species now found in small parts of their former range can actually survive in areas where they have disappeared. Are the right foods available? Is there enough ground cover (to stop owls from eating them)? Can animals from a population on the coast survive and breed in inland climates?
Using the New Holland mouse, which is now extinct from half its former NSW range, as a model species, researchers from OEH, CSIRO and ANU have established that animals from Port Stephens and Myall Lakes can happily survive and breed in chillier Canberra climates.
The next step is to determine whether habitats available in the region can still support the species. This will involve both captive feeding experiments, and a reintroduction into the ACT Government’s feral-free Mulligan’s Flat Woodland Sanctuary. New Holland mice have probably been extinct in Mulligan's Flat for over a hundred years. However, it is considered a good area to introduce the species as it is free of predators such as feral cats and foxes.
Once scientists know these species have the capacity to survive in new habitats, they can tailor management plans for the species and will be able to concentrate on targeting the most pertinent threats.
