Bell
Frog Conservation
by Javier Guiance
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Bell
Frog Conservation |
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Three species of bell frogs occur in NSW; the Green and the Golden Bell Frog (Litoria aurea); the Southern Bell Frog (Litoria raniformis) and the Yellow-spotted Bell Frog (Litoria castanea). All three are on the endangered species list in the state. The subsequent decline in numbers from their known habitats has been an ongoing dilemma for nature conservationists over the last 25 years. The introduction of the Plague Minnow (Gambusia holbrooki ) and the frog chytrid disease, Chytridiomycosis, in unison with habitat loss are believed the key factors in the species decline. The massive and sudden decline of bell frogs
The Yellow-spotted Bell Frog is considered to be almost extinct. The Green and Golden Bell Frog is still found in many sites around Sydney and along the coast to the north and south. It has been researched extensively, has a well-developed recovery plan and a number of recovery actions are currently being implemented. There has been minimal research into the Southern Bell Frog. Surveys to identify all known populations are underway, but a recovery Plan can only be drafted once they are complete. Recovery actions are therefore still a long time away. Melanie Bannerman, DEC Threatened Species Officer and Southern Bell Frog Recovery Plan Coordinator , says, "The three Bell Frog species have quite different ranges throughout NSW, with only some overlap between species. The Southern Bell Frog occurs mainly in the south-west of the state along the Murray and Murrumbidgee Rivers from the Snowies to the SA border." Time runs out for recovery plans and actions
The Green and Golden Bell Frog is mainly coastal, and the Yellow-spotted Bell Frog is known from three separate areas around Armidale and Glen Innes, near Orange and Bathurst and south on the Southern Highlands. The draft Recovery Plan for the Green and Golden Bell Frog is to be sent to affected local governments and associated agencies for endorsement, backing and feedback. Ross Wellington of the CTSU (Central Threatened Species Unit) and DEC Project Coordinator for the recovery efforts involving the Yellow-spotted Bell Frog and the Green and Golden Bell Frog said, "Most responses have now been received so it hopefully should only be a month or so until we get the final ones in and any suggested amendments agreed to and incorporated. After that it will be sent to the Minister for approval for public exhibition then printed, advertised and made widely available to the public". The formal conservation status of the Green and the Golden Bell Frog is endangered in NSW but is considered only Vulnerable at the national level. This is largely due to the perceived large populations persisting in north-east Victoria. Survey for the last surviving populations According to Ross Wellington, a recovery plan has been written for Litoria castenea (Yellow-Spotted Bell Frog), "… but the species, sensu stricto (New England population), is most likely extinct. The Southern/Central Tablelands form of Litoria castenea, which is also probably extinct, may eventually prove to have been a separate species and bring the number of Australian frogs on the 'disappeared list' to 10”, he said.
"Breeding grounds are regularly surveyed at the Homebush Bay Olympic site, Broughton Island, Kooragang Island, Arncliffe, Kurnell and North Avoca. Most recently included in these populations to be monitored are the Crescent Head and Sandgate populations. Other populations have been irregularly monitored at Culburra, Meroo Lake and other parts of the Shoalhaven. A very sensitive high altitude population has been assessed and monitored in an interim way on the southern tablelands near Captains Flat (entirely on private land). "Some of these populations are substantial in size - over 1000 individuals - others are very tenuous. Obviously details of others remain unknown, awaiting Recovery Plan actions to be approved and implemented", said Ross Wellington. An icon for the plight of frogs Media focus has assisted in raising public awareness of these endangered amphibians. Central to the high profile of the Green and Golden Bell Frog was its existence at the Homebush Bay Olympic site as well as at other high profile sites identified as premier re-development sites in Sydney, and particularly, within the Illawarra region. "The species has become somewhat iconic for the plight of frogs generally. It has been used as the motif for various initiatives, including the Foundation’s 2002 Threatened Species Campaign", said Ross Wellington. "Funding has been sought to establish community groups in support of local key populations. Such groups already exist and others will need to be formed as a Recovery Plan action", he added. The
NSW Scientific Committee has listed the frog chytrid fungus, a disease
which claims the lives of frogs worldwide, as a Key Threatening Process.
Chytrid fungus spores attack the skin of frogs and spread rapidly. It
puts many endangered frog species at further risk, including the Green
and Golden Bell Frog, Fleay's Barred Frog and the Southern Corroboree
Frog. 1. Try not to handle frogs but if necessary should wash hands between individuals. 2. Avoid moving frogs around. 3. Don't collect tadpoles and mix them with others from elsewhere 4. Obtain a copy of the Foundation funded NPWS frog hygiene protocol (PDF - 1.6MB) for further technical information. |
