One of the world's rarest mammals, the western barred bandicoot, is poised for a return to the Australian mainland, where it is thought to have been extinct for more than half a century.

The return of the bandicoot marks a new phase in the battle to turn the tide of extinctions which has seen 18 Australian native animals disappear in the last 200 years.

Once widespread across two thirds of Australia, ranging from the north west of WA to the Liverpool Plains of central NSW, the western barred bandicoot (Perameles bougainville) was last recorded on the mainland in 1929. Small remnant populations survived only on two small islands, Bernier and Dorre, off the WA coast.

Next week a team led by scientists Jeff Short and Jacqui Richards of CSIRO Wildlife & Ecology, will reintroduce the bandicoot into a meticulously-prepared refuge area on Heirisson Prong, a slender neck of land projecting into WA's Shark Bay.

The bandicoots are shy, delicate animals about the size of a squirrel, with grizzled fur, bulgy eyes and a long, pointed snout which they use to snuffle for insects and seeds in leaf litter and soil. They are nocturnal, nesting by day under dense shrubs. Their two-week gestation period makes them ideal for a program aimed at increasing numbers.

Researchers Short and Richards plan to release twelve animals, equipped with radio-tracking collars, as a part of a bid to re-establish this exceptionally rare species on the mainland. Over the ensuing weeks they will closely monitor their behaviour and fate.

The bandicoots have been bred in a captive colony on Heirisson Prong since 1995. Next week a dozen will be liberated into a 12 square kilometre area which has been fenced-off and cleared of feral cats and foxes - the predators mainly blamed for the bandicoots' demise.

Heirisson Prong is itself a remarkable story of co-operation between CSIRO, the Useless Loop community, the Shark Bay Salt Joint Venture and volunteers from Earthwatch. Together they have created a predator-proof beach-head in which endangered marsupials can gain a toehold on survival.
Its triple-layered defences consist of a high-security captive breeding area, a 12 sq km "exclusion zone" from which all predators have been removed, and a much larger 200 sq km buffer zone where cats and foxes are regularly controlled by trapping and baiting.

Although other attempts to reintroduce rare marsupials on mainland Australia have failed, the scientists are quietly optimistic of success in this case.

"A combination of fencing and regular baiting and trapping of predators allows these rare animals to breed and successfully recolonise the area," Mr Short says.

"A lot of reintroductions to the mainland have failed because of a combination of predation, and animals just scattering over the horizon, never to be seen again," Ms Richards explains.

"On Heirisson Prong we provide them with a safe, new home where there are no predators, and then try to find ways to encourage the animals not to disperse too widely."

What gives the team confidence of success is that fact that the trail has already been successfully blazed by another rare marsupial, the burrowing bettong.

Bettongs, rabbit-sized kangaroos which nest underground, were reintroduced to the mainland in 1992 and released into the fenced area three years later. Their wild population now exceeds 100 and is growing strongly.

If the bandicoot reintroduction also succeeds, the team will continue to use Heirisson Prong to reintroduce further species of desert marsupials which are close to extinction.

More information:
Jeff Short and Jacqui Richards, CSIRO 09 290 8111
Monica Martinovich, CSIRO 09 290 8106
Mobile 0417 912 611 A/H 09 293 4453