By Susan Milius
Federal researchers have added new evidence to the growing case that agricultural pesticides blowing into California’s wilderness areas have played a role in mysterious declines in frog populations.
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Traces of the common pesticides Diazinon and chlorpyrifos showed up in more than half the Pacific tree frogs sampled in Yosemite National Park, but in only 9 percent of the frogs tested at sites upwind of agricultural areas, report U.S. Geological Survey scientists Gary Fellers and Donald Sparling.