Frogs and other amphibians have occupied the marshes of the earth for more than 300 million years. Yet a new study finds the ancient species living across the United States are disappearing at increasingly fearful rates. Scientists had recognized a decline in amphibian populations since the late 1980s due to continued encroachment. But many had not estimated the severity of population loss.“They are really declining globally,” said University of Illinois Conservation biologist Jeffery Brawn. “They are declining in Illinois, Mississippi, all across the states and abroad.” This month, the United States Geological Survey reported frogs and amphibians are vanishing at a rate of 3.7 percent a year and estimate half of their remaining habitat will die in the next 20 years. “Of all vertebrates, amphibians are showing the worst population declines,” Brawn said. If things are not taken control of, the frogs, toads and other amphibians would be wiped off this planet in next 20 years, the report suggests.
In a study that was conducted over 48 species at 34 sites from California to Colorado high-country to Florida swamps for almost a decade has revealed that the declines are more widespread and severe than previously thought and amphibian populations are disappearing at an overall rate of 3.7 percent each year. The situation is almost similar inside the protected areas including the Rocky Mountain National Park, which was also part of the survey, where the population of boreal toads measured in the hundreds has declined to a handful.
The world’s top endangered species include Dusky Gopher frogs that live in the wetlands of Harrison County, Miss. Gopher frogs once croaked by the thousands there but only 60-100 individuals remain. According to ecologists, the primary threat to frogs is a lethal fungal disease known as Chytridiomycosis threatening amphibian species worldwide. The disease attacks the skin that frogs use for respiration.
USGS zoologist Stephen Corn, one of the authors of the study, said: “Amphibians are going, but a lot of other species are going, too. Snakes are declining. Mammals are declining. We’re seeing bird declines. Amphibians are probably declining at a faster rate than other groups, and they may be a little more sensitive. Amphibians are a good example of the collapse of the world’s ecosystems that we seem to be seeing right now. We’re seeing a lot of species in a lot of places declining at the same time.”
Sources:
Medill, 29 May 2013
http://news.medill.northwestern.edu/chicago/news.aspx?id=222249
NVO news, 24 May 2013
http://nvonews.com/2013/05/24/number-of-frogs-toads-declining-at-alarmi…
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