Australian Reptile Reintroductions
Western Swamp Tortoise
The Western Swamp Tortoise (Pseudemydura umbrina) (Photo: Copyright Bert & Babs Wells / CALM) is a critically endangered freshwater species that had a very small geographic range mostly within the Perth metropolitan area. Conservation efforts have been underway since rediscovery in 1953. During the 1980s a severe decline due mainly to fox predation and drought led to the development of a recovery plan, and the appointment of a recovery team by the Western Australian Department of Conservation and Land management (CALM). Since rediscovery there has been considerable research and management work, including:
- The creation of Ellen Brook and Twin Swamps Nature Reserves, in the Upper Swan area within the north-eastern part of the Perth Metropolitan Region. Both have been enlarged by purchase of adjoining land. Both are very small in terms of the tortoise’s home range and the habitat in both is considered to be marginal. Both are surrounded by fox-proof fences. The reserves require intensive management. One purchased area requires ongoing habitat restoration.
- Considerable research, much of it conducted within The University of Western Australia. This has provided an excellent basis for recovery planning and on-ground management.
- Population and environmental monitoring. Population data have been maintained since 1963; one of the longest ongoing data sets for any Australian animal population.
- Captive breeding at Perth Zoo, with initial research being conducted by CALM and later research and support being provided by UWA.
- Translocations of captive-bred tortoises. These have been to Twin Swamps Nature Reserve, and more recently to part of Mogumber Nature Reserve purchased partly to provide a translocation site for the tortoise.
- Searches for additional translocation sites. The vast majority of the tortoise’s original habitat has been cleared, drained or mined for clay. Remaining suitable sites are scarce, mostly outside the species’ known natural range and will require expensive modification.
Captive breeding is now routine, with about 40 tortoises being translocated each year. From 1994 to 2000 translocations were to Twin Swamps Nature Reserve to restock the population there, which had been reduced to less than 10 tortoises because of fox predation and drought. Since 2000, attempts are being made to establish a new population in Mogumber Nature Reserve, outside the species’ known range, as no translocation sites within the known range are available.
Contact Gerald Kuchling.