May 10, 2009

Frogs Rescued From Deadly Fungus Ravaging Montserrat

Scientists are rescuing dozens of one of the world's most rarest species of amphibians, the mountain chicken frog.

The frogs are being airlifted to safety from Montserrat in a final attempt to save it from the deadly chytrid fungus, which is ravaging their shrinking habitat and threatening extinction worldwide.

Montserrat is a tiny British Caribbean territory that is one of only two sites where the once-prevalent mountain chicken is found, but hundreds of the frogs have been killed in just the last few weeks by the fungus.

The 2-pound mountain chicken, named because locals claim its flesh tastes like chicken, is threatened by hunting and loss of habitat from a volatile volcano, and most recently by outbreaks of the chytrid fungus.

The volcano has erupted constantly since 1995 and more than half of the island's 12,000 people have had to evacuate.

Ironically enough, the volcano might be the frog's lifeline. Local officials plan to eventually reintroduce the frog to a region cut off by lava and ash that is inaccessible by foot, and hopefully fungus free.

Scientists estimate that there are only a few thousand surviving frogs and the number is decreasing everyday.

Chytrid fungus is a disease that infects the skin through which many amphibians drink and breathe. Chytridiomycosis causes lethargy and convulsions, and thickens the skin. It has spread quickly in recent decades, and some scientists believe the situation is becoming more severe as climate change is causing elevated temperatures.

"Its impact has been catastrophic," Andrew Cunningham, senior scientist with the Zoological Society of London, said about the chytrid fungus. "The mountain chicken frog has been virtually wiped out."

Gerardo Garcia, director of the herpetology department at the British-based Durrell Wildlife Conservation Trust says that experts have found 300 dead frogs and have reason to believe that hundreds more have died since the fungus appeared in late February.

Scientists are treating some of the frogs with anti-fungal baths and flying dozens of others to zoos in Britain and Sweden, where they live in temperature-controlled rooms with automatic spray systems. About 50 have been flown off the island, costing $14,000.

"We're in a situation where the species could become extinct forever," Garcia said.

Andrew Terry, Durrell's conservation manager, says that the frogs should ultimately be kept in their natural habitat, but flying them out was the only immediate solution available considering the fungus-free areas could not provide enough food.

The other stronghold of the species, nearby island Dominica, saw populations plummet beginning around 2002 as a result of the disease, which is believed to have spread to Montserrat late last year or earlier this year.

Natives on both islands used to love the frog's meat, but it is mostly tourists that request it now, said director of Montserrat's Department of Environment, Gerard Gray.

Experts are working hard to find a way to eliminate the fungus, which has killed various frog species from Asia to South America.

The Durrell trust has housed its rescued frogs in a bio-secure unit at its wildlife park in Jersey and is hoping to breed the frogs to create a population that can be reintroduced to their natural habitat in as little as two years.

ZSL London Zoo will now protect mountain chicken frogs from both Dominica and Montserrat in its captive breeding unit which includes temperature controlled rooms, automated spray systems, and areas for growing live food.

Bio-security involves full paper suits, masks and gloves worn by keepers, to make sure that no pathogens, such as the fungus, are able to enter.

The large frogs' croak is described as sounding like a small howling dog.

Gray recounts a night he heard a mountain chicken frog croaking so loudly that he thought it was under his bed.

"My wife laughed at me," he recalled, "It was in the forest where it was supposed to be."


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