SPOTTED GRASS FROG Limnodynastes tasmaniensis Gunther, 1858
This frog is highly variable in colour pattern, even between individuals from the same place. Dorsally some specimens have olive or brown mottling, others have distinctive blotches, others are unmarked, whilst many have a white, yellow, orange or red stripe running down the middle of the back.
Found in all habitats from the coastal forests to inland deserts, the Spotted Grass Frog is found throughout the eastern half of Australia and Tasmania.
This frog is usually caught when sheltering under debris near grassy swamps, dams and lagoons; its' preferred habitat.
Sometimes massive numbers may congregate in a very small area. Breeding at any time of year, the call is a rapid 'uk-uk-uk' in NSW and further north, and a single 'click' sound sometimes repeated, elsewhere.

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.