About 35 bilbies bred in captivity have been released across the South-West in an attempt to bolster stocks of the increasingly endangered mammal.
At one time found across 70 per cent of Australia, their numbers have been decimated by foxes and feral cats to the point where scientists no longer know how many are left in the wild.
Now existing in scattered and isolated populations across arid regions of WA, the Northern Territory and south-west Queensland, the bilbies have returned to the South-West for the first time since their extinction from the area 30 years ago.
Environment Minister Donna Faragher said scientists were confident the mammals would survive within the nature reserve at Perup, 50km north-east of Manjimup.
Mrs Faragher said anecdotal evidence suggested bilbies were present within the Perup area until the late 1970s so there was suitable habitat for the species.
Some of the animals were bred and flown from the Department of Environment and Conservation's Peron captive breeding centre at Shark Bay, while others were taken from breeding programs at the Dryandra Woodland, south of Perth.
Their reintroduction into the South-West is part of a national recovery plan for bilbies.
Earlier this month the endangered mammal was ranked 11th on WA's most threatened species list.
The department will monitor the released animals through radio tracking and trapping to check their survival in the wild.
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