Tuesday, November 07, 2006

Disappearing Amphibians

Today's warmer weather, heavy rain and ensuing puddles have elicited an amphibian chorus. The treefrog pictured here is either an Eastern Gray Treefrog or a Cope's Gray Treefrog. The two look identical though the Cope's Gray Treefrog has half the number of chromosomes and a slower trill than the Eastern Gray Treefrog. More Francis Beidler Forest amphibian images can be seen at: http://www.beidlerforest.org/education/amphibians.htm

Worldwide amphibian populations are in decline with a third of the 5,700 species considered threatened. In the last 20 years, 168 amphibian species have become extinct. Habitat loss is the main factor for the decline with disease, overexploitation (pet trade), and climate change being contributing factors. Recently, however, a new and deadly efficient culprit has been identified.

Chytrid fungus invades the amphibians' skin and distrupts their water balance. No continent has been spared as scientists rush to collect specimens from the wild in an effort to prevent additional extinctions. The fungus likely was spread by African frogs used for medical purposes or South American bullfrogs imported live for their meaty legs. South Carolina is included as an area where amphibians are "most threatened." (National Geographic, Jan. 2006)

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