Conservation efforts to save one of the nation’s most critically endangered reptiles from extinction reached another milestone recently with the release of 30 Western Swamp Tortoises (Pseudemydura umbrina) into Moore River Nature Reserve, north of Perth.
Department of Biodiversity, Conservation and Attractions (DBCA) Senior Research Scientist Dr Gerald Kuchling said the release was crucial in strengthening wild populations of the species with only four known and monitored populations in Western Australia.
“The western swamp tortoise is Australia’s rarest and most critically endangered reptile, with habitat loss, low rainfall and predation by foxes, pigs, rats and ravens the major causes for its decline,” he said.
“Less than 50 individuals survived 30 years ago, but since 1988 in a collaborative partnership with Perth Zoo we have been running a successful breeding program and have been able to translocate captive-bred juveniles to three sites since 1994.
“Moore River Nature Reserve offers good habitat and ongoing control of feral predators and this translocation allows us to boost the western swamp tortoise population there, which was first established in 2007.
“Some of the 146 juveniles previously released there have already reached maturity and started breeding with new hatchlings recorded.”
Perth Zoo keeper, Bradie Durell, said the tortoises were weighed, measured and marked before release to ensure their growth and progress in the reserve can be monitored over coming years.
“We have successfully bred over 1040 western swamp tortoises since the program began almost 30 years ago,” he said. “The ones released are generally aged around three-years-old as they are less vulnerable to predators and to drought than hatchlings.
“The tortoises are a long-lived native species but take around eight to 15 years to mature and have a slow breeding rate.”
The species’ recovery actions are part of DBCA’s wildlife program Western Shield. The species recovery program is coordinated by DBCA, including the Perth Zoo, the University of Western Australia, the Friends of the Western Swamp Tortoise community group and Ellen Brockman Integrated Catchment Group.
Danielle Henry, Media and Communications Manager, Perth Zoo