In a pond in Twin Swamps Reserve, a western swamp tortoise goes about her business, oblivious to the dire perils that are facing her species. The western swamp tortoise (Pseudemydura umbrina) is Australia's most critically endangered reptile. It makes its home in temporary wetlands in the Swan Valley, north of Perth, Western Australia. They are active in winter, feeding on small aquatic arthropods in shallow ponds. When the ponds dry out during the summer, the reptiles aestivate in cracks in the clay or under vegetation.

Thanks to a concerted conservation effort, there are about 500 tortoises alive today (200 in captivity at Perth zoo), up from a low of about 30 in the mid-1960s. With specialised requirements for ephemeral swampland, this species already had a highly restricted distribution before European settlement and most of their former habitat has been drained and developed. Other threats include predation by introduced foxes and a pronounced drop in regional rainfall since the 1970s.

Note: in Australia a "turtle" refers to any flippered, fully-aquatic chelonian  (ie. sea turtles and the pig-nosed Carettochelys) while "tortoises" are   freshwater semiaquatic chelonians of the family Chelidae. There are no terrestrial testudinid tortoises in the classical European sense.