Endangered mouse returns after almost half a century

A special breeding program is returning the endangered Pookila mouse to a Melbourne botanic garden. (HANDOUT/ZOOS VICTORIA)

A breeding program has returned an endangered rodent to a botanic garden where it has not been sighted for 48 years.

A group of 28 Pookila, a mouse native to southeast Australia, has been reintroduced at Royal Botanic Gardens Cranbourne as part of a breeding program by Melbourne Zoo and Moonlit Sanctuary.

Pookila have been in decline since their discovery in 1970 and are considered extinct in seven of their 12 known locations.

About 3000 are believed to exist in the remaining five locations in eastern Victoria.

Pookila have been in decline since their discovery in 1970, with some 3000 left in eastern Victoria. (HANDOUT/ZOOS VICTORIA)

Native rodent biologist Phoebe Burns said Zoos Victoria was proud to lead the reintroduction program as part of wider efforts to recover the species.

"This is the culmination of decades of work by dedicated conservation scientists," Dr Burns said.

"It's so exciting to be at the point where we get to return the Pookila to the Royal Botanic Gardens Cranbourne after nearly 50 years' absence."

The breeding program matched Pookila from different locations to ensure greater genetic diversity than those remaining in the wild.

They have been housed in a small, fenced-off area ahead of their release into the broader gardens in the next six to eight weeks.

"The soft-release process will allow Pookila to adjust to their new home, get used to the weather, dig burrows and experience Cranbourne gardens while remaining safe and well-fed," Dr Burns said. 

Shy and nocturnal, the endangered Pookila rodents feed on native plant seeds, leaves and fungi. (HANDOUT/ZOOS VICTORIA)

"Once they're ready, we'll let them look after themselves, but continue to keep a close eye on them."

Pookila are shy and nocturnal and can be distinguished from common mice by their multi-coloured tail, big eyes, soft, thick fur and lack of "mousey" musk.

The small, burrowing rodent lives in open heathland and coastal areas and mostly feeds on native plant seeds, leaves and fungi.

"Royal Botanic Gardens Cranbourne is home to over 450 native plant species in its bushland, with native grasses and landscapes which will provide many safe hiding spots for this little creature," Ricardo Simao from the gardens said in a statement.

"We also have predator-proof fencing to protect them from cats and foxes."

The project also involves the Department of Energy, Environment and Climate Action, Gippsland Water and Parks Victoria.