Growling Grass Frog, Litoria raniformis, at Neerin Flat in Victoria
Image: Peter Robertson
Source: Wildlife Profiles Pty Ltd
Description
The Growling Grass Frog (also known as the Green and Golden Frog, the Southern Bell Frog or the Warty Swamp Frog) is one of the largest frog species in Australia. The females (60-104 mm) grow much larger than the males (55-65 mm). Their colour is variable but is usually olive to bright emerald green with irregular bronze, gold brown or black spotting. Their backs are warty and usually have a pale green stripe down the middle.
Growling Grass Frog, Litoria raniformis
Photographer: Peter Robertson
Source: Wildlife Profiles Pty Ltd
Distribution
Growling Grass Frogs are found in Victoria, Tasmania, New South Wales, ACT and South Australia. In Victoria they have disappeared from much of their former range, but isolated populations persist in the greater Melbourne area, south-west, central and eastern Victoria. Growling Grass Frogs were introduced to New Zealand in 1867 where they are now widespread.
Habitat
Growling Grass Frogs like to live amongst reeds, sedges and rushes growing in and along slow moving streams, ponds, lagoons, swamps, lakes and farm dams. They can be found floating in warmer waters that are between 18 and 25 degrees.
Life History & Ecology
Males usually call while floating in open water. The call is several short grunts followed by a long deep growl that lasts for about one second. Growling Grass Frogs breed in the spring and summer, usually from November to March. The females lay their eggs in a loose mass amongst floating vegetation. The tadpoles are pinky-grey with yellowy fins. They can reach 100mm before they metamorphose and turn into frogs.
Growling Grass Frogs feed primarily on ground-dwelling insects such as beetles, termites, cockroaches, moths, butterflies and insect larvae. However, they also eat lizards, snakes, fish and other frogs, including smaller members of their own species. They are not active hunters; rather, they sit and wait for their prey to come to them.
Threats
Loss and fragmentation of suitable habitat is a continuous threat to Growling Grass Frogs. Chytrid fungus, an infectious disease widespread in frog populations in eastern Australia, is also believed to be having a significant effect on Growling Grass Frog populations. Reductions in rainfall rates are also thought to be a significant threat.
Growling Grass Frogs were once so abundant In Victoria that they were used for dissections in universities and to feed the snakes at the Melbourne Zoo. The various threats to their populations are forcing them to live in the lower reaches of our catchments.
Conservation Status
National conservation status
The Growling Grass Frog is listed as vulnerable under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999.
Victorian conservation status
The Growling Grass Frog is listed as endangered under the Victorian Flora and Fauna Guarantee Act 1988.