Experts warn of total amphibian extinction, fearing cataclysm

Experts warn of total amphibian extinction, fearing cataclysm
By John Biemer
CHICAGO TRIBUNE

CHICAGO – Predicting a mass extinction of the world's frogs, toads, newts and salamanders, 50 international amphibian experts are sending out an unprecedented call for an urgent global mission to avert a cataclysm.

The plea, published in today's edition of the journal Science, is meant to be a wake-up call for a broader range of scientists and policy-makers about threats to Earth's amphibians, considered canaries in the coal mine for all of nature.

“For the first time in modern history, because of the way that humans are impacting our natural world, we're facing the extinction of an entire class of organisms,” said Claude Gascon, a herpetologist with Conservation International. “This is not the extinction of just a panda or a rhino; it's a whole class of organisms. Certainly if it were impacting mammals, we would be taking this a lot more seriously.”

Amphibians are more susceptible to changes in the environment than other animals because they have permeable skin that absorbs water and oxygen, and their lives depend on clean, fresh water. Almost one-third of the 5,743 known amphibian species worldwide already are threatened by a combination of habitat loss, climate change, pollution, pesticides, ultraviolet radiation and invasive species, with up to 122 having become extinct since 1980. But scientists believe both figures could be underestimates because they cannot evaluate species quickly enough.

The latest, most pressing threat is a rapidly spreading fungal disease predicted to wipe out about half the amphibian species within six months of its entering a new ecosystem. Chytridiomycosis, which damages the skin, is being described as the final straw – leading to today's unusual appeal.

“It's unprecedented in terms of the magnitude of the problem, just how many species are being hit,” said Bob Lacy, the Brookfield (Ill.) Zoo's population geneticist and chairman of the Conservation Breeding Specialist Group. “It's unprecedented in the global impact, the sites around the world, and it's unprecedented (because of) the speed of it. Species are going extinct very fast.”

Andrew Blaustein, a zoology professor at Oregon State University and one of the pioneers in the field, said, “These are bioindicators that something is wrong with the planet.”

Signers to the statement include many leading herpetologists, but also disease experts, field ecologists, physiologists, evolutionary biologists and representatives of government agencies and nonprofit conservation groups.

They are calling for a five-year, $400 million project to pluck certain susceptible species out of harm's way and put them in safe, regional breeding and research centers, as well as zoos and universities around the world – a program some have described as a modern Noah's Ark. They hope the money will come from a range of sources: government agencies, conservation groups, foundations, the private sector and individuals.

Amphibians consume insect pests that can carry diseases harmful to humans and also provide meals themselves for fish, birds, snakes and other animals. But as the amphibians disappear, that sets off ripple effects that can disrupt the ecosystem.

The potent secretions of amphibian skin also hold potential for biomedicine and biotechnology.

Although scientists are trained to be skeptical and wait for ironclad evidence before reaching conclusions and taking action, Lacy said enough data now suggest time is too precious to wait any longer. There is no known way to stop the fungal disease, which already has spread down Central America and wiped out populations in Australia.

The project should have started “last year,” Lacy said.