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Pesticides are involved with population declines of amphibians in the California Sierra Nevadas

January 1, 2001

Several species of frogs and toads are in serious decline in the Sierra Nevada Mountains of California. These species include the threatened red-legged frog ( Rana aurora ), foothill yellow-legged frog ( R. boylii ), mountain yellow-legged frog ( R. muscosa ), Cascades frog ( Rana cascadae ), western toad ( Bufo boreas ) and Yosemite toad ( B. canorus ). For many of these species current distributions are down to 10% of historical ranges. Several factors including introduced predators, habitat loss, and ultraviolet radiation have been suggested as causes of these declines. Another probable cause is air-borne pesticides from the Central Valley of California. The Central Valley, especially the San Joaquin Valley, is a major agricultural region where millions of pounds of active ingredient pesticides are applied each year (http://www.cdpr.ca.gov/dprdatabase.htm). Prevailing westerly winds from the Pacific Coast transport these pesticides into the into the Sierras.

Publication Year 2001
Title Pesticides are involved with population declines of amphibians in the California Sierra Nevadas
DOI 10.1100/tsw.2001.36
Authors D. W. Sparling, G. Fellers, L. McConnell
Publication Type Article
Publication Subtype Journal Article
Series Title Scientific World Journal
Index ID 5224596
Record Source USGS Publications Warehouse
USGS Organization Patuxent Wildlife Research Center
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