NORTHERN WATER HOLDING FROG Cyclorana australis (Gray, 1842)
This large robust frog attains 10 cm in length. Although a well built burrowing frog it is actually more closely related to other tree frogs, (with which it is sometimes classified at family level), than other Australian burrowing frogs.
Like most burrowing frogs it appears to hide underground during dry seasons, in a 'cocoon-like' set up. It is common throughout Northwest and nearby parts of Australia. Found in most habitats it is most commonly found crossing roads after tropical thunderstorms.
This species has cannibalistic tendencies, and appears to usually breed in dams and semi-permanent water holes, usually during summer. It's call is a distinctive and loud 'Honk,Honk'. The colour of this species changes, depending on the physical state of the frog, its age and other factors. It ranges from olive, brown, grey and even pink above.
Aboriginals in desert areas used these frogs as a source of water during droughts.
They did this by digging up water engorged frogs in dried up ponds. They then placed the rear of the frog in their mouth and squeezed the water from the frog. Hence the frogs' name.

The above was from the book Australian Reptiles and Frogs by Raymond Hoser and now available on a fantastic CD-Rom along with a vast amount of other information, papers and the like on reptiles, frogs and other wildlife.