| SAN JOSE, Costa Rica
SAN JOSE, Costa Rica Global warming is the top
suspect for the disappearance of 17 amphibian species from
Costa Rican jungles, scientists said on Tuesday, warning monkey
and reptile populations were also plummeting.
Five of the amphibian species were found only in Costa
Rica, meaning their disappearance from the country's jungles
spells extinction, said Alvaro Herrero, a biologist with Costa
Rica's National Biodiversity Institute.
Among the now-extinct species is the Golden Toad, named for
its shimmering yellow color, and two varieties of Harlequin
frog, identified by their black and green stripes.
Scientists have yet to identify a precise mechanism for the
disappearance of the amphibians, which began decades ago, but a
prime suspect is a fatal fungus that has invaded their
habitats, Herrero said.
"It is believed climate change is raising temperatures
allowing a skin fungus to enter the places where the amphibians
resided," he said.
Several studies in recent years have linked the rapid
disappearance of many of the world's frog and toad species to
About a third of the 5,743 known species of frogs, toads
and other amphibians are classified as threatened, according to
the Global Amphibian Assessment survey.
Human activities are wiping out three animal or plant
species every hour, the United Nations said on Tuesday, the
International Day for Biological Diversity.
A strong consensus of scientists believe that global
warming is the result of the release of greenhouse gases like
carbon dioxide into the atmosphere.
Scientists say the amphibian die-off is a harbinger of
things to come in the biologically rich tropical forests of
"It's going to be a fact that we see a large extinction,"
said Rodrigo Gamez, president of the biodiversity institute.
In La Selva, a biological station in northern Costa Rica
run by Duke University's Organization of Tropical Studies,
scientists have found a 75 percent decline in amphibian
population over the last 35 years.
The precise reason for the La Selva decline is not known,
but scientists suspect that higher temperatures are inhibiting
plant growth and thus diminishing the volume of decomposing
leaves in which the amphibians thrive.
Populations of reptiles and insects also seem to be on the
decline around the biological station, he said.
Another disturbing trend in the country is the decline of
Costa Rica's monkeys. Monkey populations have fallen by 30
percent in recent years, according to Alfo Piva, executive
director of the biodiversity institute.
He said a lot was unknown about the changes in Costa Rica's
jungles. "Much study is still lacking," he said.
Costa Rica occupies about 0.03 percent of the Earth's land
mass, but contains about 4 percent of its animal and plant