Fewer than 3,000 Pookila mice are thought to be left in the wild in Victoria but a new captive breeding program hopes to turn the endangered rodents' fortunes around.
Zoos Victoria's native rodent biologist Phoebe Burns said the mouse had become extinct at seven of the 12 sites the species was known to inhabit in Victoria.
"The Pookila has undergone massive declines here in Victoria … our research shows they're only persisting at five of those sites [in Gippsland]," Dr Burns said.
"The 2019 drought in Gippsland really knocked them around so we think there's fewer than 3,000 animals left in the wild at the moment, which is pretty bad.
"They used to be found all the way out across to Anglesea and south-east Melbourne but the only remaining sites now are at [Wilsons Promontory] and around Loch Sport."
Dr Burns said the Pookila mouse played an important environmental role by spreading seeds and fungal spores and keeping soil healthy.
"They are one of about 67 different native species of mice and rats that we have in Australia but 15 of those species have already gone extinct," she said.
"So it is really important to try and look after the ones that we have left like the Pookila."
Land clearing, fire and introduced predators including foxes and cats have had an impact on the species' numbers.
The small creature is listed as endangered in both Victoria and Tasmania and vulnerable in Queensland and the ACT.
Zoos Victoria is working with Moonlit Sanctuary, Parks Victoria and other organisations to save the species.
Playing matchmaker
Dr Burns and the team recently collected 22 Pookila mice from the wild for the captive breeding program at Melbourne Zoo.
"We've taken individuals from the wild and we're pairing them with compatible mates, genetically diverse pairings."
The animals will eventually be released at sites to improve the population's genetic makeup and in places where threats like cats can be managed.
The team is also hoping to set up an insurance population at the Cranbourne Botanic Gardens.
"Where we can have them free-roaming but in an area where there are no cats," she said.
"Then we can continue to captive breed them so that we can produce the genetically healthy animals to pop back out into the wild."
