Conservation Programs

The Gilbert’s Potoroo is Australia's most endangered marsupial species.

After more than 80 years listed as an extinct species, in 1994 around 30 Gilbert’s Potoroo were discovered near Two Peoples Bay in Western Australia.

Despite consistent breeding and regular predator baiting for the past 12 years, the Gilbert’s Potoroo population has remained static with no significant increase reported.

Location in wild
Two Peoples Bay Nature Reserve, Western Australia

Numbers in wild
Only 30-40 individuals

Threats
Fire, predation by cats and foxes

Type of involvement
Research into potoroo reproduction and development of cross-fostering techniques for accelerating breeding

Partners
Department for Environment and Conservation (WA)

Prior to European settlement there were 10 species of rat kangaroo distributed throughout Australia. Three of these species, the Desert Rat Kangaroo, the Broad-faced Potoroo and Gilbert’s Potoroo were thought to have gone extinct in the last two centuries.

However, in 1994, a survey for Quokka’s in Two Peoples Bay Nature Reserve found a small population of Gilbert's Potoroos, more than 80 years after they had been listed as extinct.

Like most mammals in Australia, Gilbert’s Potoroo is nocturnal. Along with the Long-footed Potoroo, this is the most fungi dependent mammal known, as over 90% of its diet at most times of the year is made up of fungi.

Field data suggested that the habitat in which the Gilbert’s Potoroo currently reside is at holding capacity, so other sites, including other reserves, off-shore islands and large predator proof enclosures are being investigated to facilitate population expansion. The relationship between food (truffle) availability, climatic variable and potoroo abundance is at present unknown.

In an effort to increase the population size as rapidly as possible and to provide animals for these new areas, a captive breeding colony was established from seven wild Gilbert’s Potoroos in 2001. In contrast to the situation in the wild however, captive breeding success and recruitment have been poor, with the artificial diet thought to be a factor in this breeding failure as this diet may not mimic closely enough the potoroos wild diet of truffle-like fungi.

Cross fostering trials by Conservation Ark staff in Long-nosed Potoroos, brush-tailed bettongs and burrowing bettongs have concluded that the long-nosed potoroo is the most suitable surrogate species for Gilbert’s Potoroo joeys. Taking young from wild mothers and fostering them into other species can help ensure that breeding and recruitment is high and that no further decline occurs in the genetic diversity within the population.

Preliminary cross fostering trials in Gilbert’s Potoroo have proved very encouraging with 2/2 Gilbert’s Potoroo young fostered directly from wild mothers to Long-nosed Potoroo surrogate mothers surviving to independence.

Recently, a new colony has been established in Waychinicup National Park, 25 km east of Albany. A new fence has been built to help keep out feral predators and rabbits, and 7 Gilberts Potoroos have been released into it. The Department of Conservation and Environment will be radio-tracking them to see how well they survive.