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Western Swamp Tortoise (Pseudemydura umbrina) Australia’s Most Critically Endangered Reptile Conservation Status NATIONAL: Critically Endangered (Environment Protection and Biodiversity Conservation Act 1999) Description The Western Swamp Tortoise’s colour varies with age and the type of swamp it lives in. It can be yellow-‐brown or black on top and black, yellow or cream underneath. It grows up to 15 cm in length with a squarish shell, broad shell. Its legs are short and covered in scutes (similar to fish scales) and their feet are webbed, with large, well developed claws. They have a short neck covered in small bumps, one big scale protecting the top of the head and small growths under their chin. They have a very interesting lifecycle spending the hotter part of the year from summer to autumn underground. This process, called aestivation, allows the Western Swamp Tortoise to escape the intense summer heat and dehydration from the dry conditions. It comes out of aestivation and becomes active in winter when the swamps fill with water and remains active through to spring until it becomes too hot and dry again. Distribution Historically, the species has only been recorded from scattered localities in a narrow strip (3–5 km wide) of the Swan Coastal Plain, Western Australia. The range spans from Perth Airport at Guilford to near Pearce Royal Australian Air Force Base at Bullsbrook. Between 1960 and late 1980s the number of Western Swamp Tortoise declined from 250 to just 15-‐25 mature individuals. The species currently occurs in a single viable population in the wild at the Ellen Brook Nature Reserve. Two further populations at Twin Swamps Nature Reserve and Mogumber Nature Reserve have populations that are maintained by supplementation with translocated individuals. Diet The Western Swamp Tortoise is carnivorous. It eats crustaceans, insects and their larvae. They only feed in the cooler months when the water temperature is between 14 and 28 degrees Celsius. Breeding The Western Swamp Tortoise is a long-‐lived (up to 100 years) and slow-‐reproducing species. Females reach maturity at about 10-‐15 years. There are records of the Western Swamp Tortoise reproducing at over 60 years of age. Mating takes place only in water, occurring mostly in winter. One clutch of 3–5 brittle-‐shelled eggs is laid in a shallow underground nest in November or early December. The eggs hatch the following winter as the temperature begins to fall. Hatchlings are only the size of a 10 cent coin. Threats The decline of the Western Swamp Tortoise is believed to be due to a combination of a restricted geographic range, habitat clearance for agriculture, urban and industrial development (including clay mining), increasing aridity (due to climate change), predation by foxes and other animals, inappropriate fire regimes and drainage of swamp habitat. Recovery Plan There is a Recovery Plan and Program for the Western Swamp Tortoise coordinated by the WA Department of Environment and Conservation. A recovery team comprising representatives of the Department of Environment and Conservation, the University of WA, Perth Zoo, the Friends of the Western Swamp Tortoise and the World Wide Fund for Nature works to implement the recovery program. The aim being to have four or five secure, viable populations, rather than the one that currently exists. Perth Zoo has developed a highly successful captive breeding program. Juvenile tortoises bred at Perth Zoo have been reintroduced back to their natural habitat at Twin Swamps Nature Reserve over the past decade. More recently two new sites at Mogumber Nature Reserve and Moore River National Park have been trialled with some releases. Other activities include rehabilitation of habitat, creating fenced reserves to keep out foxes and providing educational and promotional material and activities on the tortoise and the recovery program. References & More Information Department of Sustainability, Environment, Water, Population and Communities 2010. Pseudemydura umbrina in Species Profile and Threats Database. Commonwealth Government, Canberra. www.environment.gov.au/sprat. Friends of the Western Swamp Tortise. http://www.westernswamptortoise.com/ Aug-‐13 www.fame.org.au