Green and golden bell frog, Ranoidea aurea NSW status, Endangered. Commonwealth status, Vulnerable.
Eats insects, worms and small vertebrates. Sunbakes to aid digestion.
Tadpoles take 3-11 months to mature.
Classification
A ground dwelling frog in the tree frog family, one of Australia’s largest frogs the adults are between 4.5-11cm in size.
Very similar to other frogs in the Ranoidea genus, the green and golden bell frog is able to hybridise and is often found together with the closely related growling grass frog (R. castanea) and yellow spotted bell frog (R. raniformis).
“The species is now classified within the Ranoidea aurea complex, a closely related group of frogs in the genus Ranoidea.[4] This complex is scattered throughout Australia: three species occur in south-east Australia, one in northern Australia, and two in Southwest Australia.”
“Ranoidea aurea is equally and most closely related to R. castanea and R. raniformis. A microcomplement fixation technique using serum albumins has indicated the species closest to R. aurea is R. ranifomis. Albumin immunological distance data suggest no differentiation between the two, and the green and golden bell frog evolutionally separated from the other two species about 1.1 million years ago.”
From the Wikipedia entry on the green and golden bell frog (GGBF)
Offsets
The GGBF faces steep population declines in the remaining habitat, and is listed as endangered in NSW, where threats to biodiversity are largely managed with an “offset” mechanism. The Biodiversity Offset Market puts a monetary value onto threatened species and their habitat, this can be used to draw up compensation deals. These values are known as “species credits” and given that the market has been established by government to facilitate development in environmentally sensitive areas, outcomes favour developers. The cost of offsets is never a deterrent to a major development because the rules will be altered in such cases. There’s been no recorded improvement in environmental outcomes using an offset scheme, for frogs or any other species, anywhere, ever.
The market price on endangered frogs fluctuates depending on supply and demand for sites to be destroyed versus sites that might potentially be saved. We could speculate that the price should also reflect frog population health and numbers, but it’s unlikely that populations are monitored sufficiently to establish if offsets are effective. When it rains do the prices go down as more frogs reproduce? When it’s dry do prices go up as frogs perish? As frogs head to extinction does the price reflect the intrinsic value of another lost species. Does any of this economic activity increase the extent of frog habitat? Probably not, but it provides job opportunities for biologists who might otherwise raise concerns about development threats.
According to wikipedia, only 40 sites remain where GGBFs can be found. However species credit market prices dealing in habitat loss continue to fluctuate. How is it that the habitat market offset price can rise and fall while habitat loss continues in one direction?
On the 11th Nov 2022 species credit price for the green and golden bell frog was $22,348. The most recent sale of GGBF species credits on 28th Oct 2024 was $1,651, a 93% fall in value, yet the underlying conservation concerns are as dire as ever, chytrid fungus and habitat destruction remain as major threats.
No one can properly explain the species market, but green and golden bell frogs remain endangered and have vanished entirely from 90% of its previous recorded range. Meanwhile several government enquires at state and federal level have established that the biodiversity offset market is a failed concept.
Wetlands
The key to conservation is protecting habitat. Wetlands provide habitat for frogs but are just as crucial for birds, and frogs provide protein for birds. It’s entirely possible for an endangered bird to eat an endangered frog, such are the complications of conservation and over reliance on a diminishing area of suitable habitat.
Kooragang Island is one of three East Australian Islands where GGBF are found, and also major industrial hub. In 1983 a Kooragang wetlands rehabilitation and nature reserve were formed. 1984 it was declared a Ramsar site of 2926 hectares.
“The Hunter Estuary Wetlands Ramsar site is extremely important as both a feeding and roosting site for a large seasonal population of shorebirds and as a waylay site for transient migrants. Over 250 species of birds have been recorded within the Ramsar site, including 45 species listed under international migratory conservation agreements. In addition, the Ramsar site provides habitat for the nationally threatened Green and Golden Bell Frog, Estuary Stingray and Australasian Bittern.” Aust Gov DCCEEW 2019
Sources
https://en.wikipedia.org/wiki/Green_and_golden_bell_frog
https://australian.museum/learn/animals/frogs/green-and-golden-bell-frog/
https://www.environment.gov.au/cgi-bin/wetlands/ramsardetails.pl?refcode=24
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