The mass extinction of amphibian species would be catastrophic, say the experts, who are calling on all people to help save frogs, toads, salamanders, newts and caecilians.

A THIRD to a half of all amphibian species is in danger of disappearing in our lifetime, says Steven van der Spuy, the chief executive officer of the Johannesburg Zoo.

Amphibians, which act as bio-indicators, are listed as threatened; their potential mass extinction could be the most cataclysmic since the dinosaur era. But the Amphibian Ark is racing to the rescue, partnering the World Association of Zoos and Aquariums, the IUCN/SSC Conservation Breeding Specialist Group, and the IUCN/SSC Amphibian Specialist Group.

The SSC is the Species Survival Commission; it is a unit of the IUCN, the International Union for Conservation of Nature, based in Switzerland.

African clawed: Frogs act as bio-indicators but face threat of extinction

 Having declared 2008 the Year of the Frog, the Amphibian Ark and its partners are working to raise awareness crucial to the survival of amphibians, and to draw attention to conservation efforts. Calls are being made to the public, the United Nations, governments, international organisations and world zoos to team up to save the species.

According to the IUCN Red List of Threatened Species, 1 856 of the 5 743 known amphibian species - almost one in three - are threatened with extinction. "The [Johannesburg Zoo] has made resources and space available for the captive propagation of these frogs," Van der Spuy notes.

Amphibian species in the city have declined markedly in recent years, mainly because of the destruction and degradation of their habitats - mostly wetlands - for the construction of residential developments.

Frogs are severely affected by habitat loss; climate change; pollution; pesticides; global warming, which will ultimately lead to a depletion of the ozone layer; and human appetite, among other factors.

Nature's barometers
Considered as nature's barometers, amphibians are among the first species to respond to biodiversity changes. Their inherent biological secrets can lead to important medical advances and the species are integral to the food web.

Clayton Cook, a specialist herpetologist - a scientist who studies snakes, reptiles and amphibians - confirms that frogs are excellent indicators of the state of the environment.

"As they live both on the land and in the water, mainly for breeding purposes, frogs are exposed to both water pollution and land pollution," Cook says. Their presence in rivers or streams is an indicator that the water quality is still acceptable.

In South Africa alone, 25 species are listed in the current Red Data Book as threatened; of these, four are critically endangered, eight are endangered, eight are vulnerable, and five are near-threatened. The giant bullfrog, the only species endemic to Gauteng, has been listed as near-threatened because of habitat degradation, Cook notes.

Amphibians include frogs, toads, salamanders, newts and caecilians.

One of the major threats to frogs around the world is a fungal infection, chytrid fungus, which has resulted in a massive decline in the population of frogs - even the extinction of certain species in Australia, Central America, the United States and Spain.

"The fungus originated in South Africa from the Xenopus laevis. These frogs were exported around the world in the 1960s as they were used for pregnancy tests. Urine was injected into the frogs and if they laid eggs the woman was confirmed to be pregnant," Cook explains.

Individual input
Sir David Attenborough, the conservationist and the patron of the campaign, notes that the global zoo and aquarium community has taken on this challenge with enthusiasm. However, there is more that communities can do to curb the disaster.

"Implementation calls for financial and political support from all parts of the world," Attenborough says.

Without an immediate and sustained conservation effort to support captive management, Attenborough says that hundreds of species could become extinct in our lifetime.

Funds raised through this worldwide campaign will help to establish initiatives such as rescue missions, training workshops and co-operatively managed centres for better education and awareness in all communities.

Catastrophic
Jeffrey Bonner, the chairman of the Amphibian Ark and the president and chief executive of the St Louis Zoo in the United States, warns that the widespread extinction of amphibians could be catastrophic.

Bonner points out that amphibians offer many benefits and are a critical part of a healthy world. "They play an important role in the food web as both predator and prey, eating insects, which benefits agriculture and minimises disease spread."

Their skin contains substances that protect them from some microbes and viruses, "offering promising medical cures for a variety of human diseases".

Cook echoes this, saying amphibians are an important link in the food chain, feeding on numerous problematic insects like mosquitoes, as well as on rodents and even snakes, in the case of the giant bullfrog.

"A healthy frog population significantly reduces problematic insects."

He points out that conservation efforts have increased in the past seven months. The main objectives of the 2008 Year of The Frog campaign are:

• To forge partnerships between zoos, aquariums, botanical gardens, and private and public institutions around the world to ensure the global survival of amphibians;
• To highlight ways in which the public can make positive contributions to conservation through their daily activities or routines;
• To stimulate a sustained and long-term interest in amphibian conservation and related interactions with the wider environment;
• To raise increased awareness about the protection of biodiversity through the conservation of amphibians; and
• To strengthen zoo communities as fundraisers and global promoters of amphibian conservation.

There are a number of things members of the public can do:

• Do not move frogs from one part of the country to another - they usually die as a result because they cannot adapt to new environments;
• Encourage frogs to make their home on your farm or smallholding, in your garden, or in your school grounds by avoiding the use of pesticides and chemical fertilisers;
• Prevent frogs from drowning in swimming pools or dams by leaving a wooden plank floating in them for frogs to climb on to be rescued; and
• Create a simple pond at your home to provide essential breeding habitats as well as a place for foraging and shelter.

Related stories:

• Kids, leap on over to the zoo
• Kids learn about threats to frogs
• Zoo takes to breeding frogs
• New zoo boss - wild about wildlife

Related links:

• Johannesburg Zoo
• Amphibian Ark