leopard frog

Leopard Frog & Weed Killers
. . . (Rana pipiens)
Native to North America.

Popular Weed K iller Feminizes
Native Leopard Frogs Across Midwest


"Berkeley - Native male leopard frogs throughout the nation's Corn Belt
are being feminized by an herbicide, atrazine, used extensively to kill
weeds on the country's leading export crops, corn and soybeans, according
to a survey conducted by University of California, Berkeley, biologists and
reported this week in Nature.

The UC Berkeley scientists also showed that male leopard frogs raised in
laboratory tanks contaminated with atrazine develop egg cells in their testes
and essentially turn into hermaphrodites. These sexual abnormalities were
observed at atrazine levels as low as 0.1 parts per billion (ppb), 30 times
lower than the current allowable limit for atrazine in drinking water set by the
Environmental Protection Agency.

These findings, added to earlier evidence that atrazine demasculinizes two
other species of frog, suggest that the herbicide could be a factor in the decline
of frogs and other amphibians in the United States and around the world, the
authors say. Atrazine has been used on crops since 1956 and currently is the
most widely used herbicide in the nation. [...]

Atrazine is so widespread that it can be found far from agricultural areas
and even in rainwater and snow. At one site in Nebraska, Hayes found that rain
and tap water contained enough atrazine to disrupt normal male development
in amphibians.

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Hibiscus west-facing cascade West-
SNAPPER! SNAPPER! watewr bottle Water

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Photograph by Cliff Crego © 2006 picture-poems.com

(created: VIII.13.2005)