Environmental contaminants in California condors

Stanley N. Wiemeyer; J. Michael Scott; Marilyn P. Anderson; Peter H. Bloom; Charles J. Stafford

doi:10.2307/3801228

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Environmental contaminants in California condors

Stanley N. Wiemeyer·J. Michael Scott·Marilyn P. Anderson·Peter H. Bloom·Charles J. Stafford

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Abstract

Five wild California condors ( Gymnogyps californianus ) that died in 1980-86 were necropsied and tissues were analyzed for environmental contaminants. Three died of lead (Pb) poisoning, 1 presumably of cyanide (CN) poisoning, and 1 nestling of handling shock. Organochlorine concentrations were low in 4 condors that were analyzed for these contaminants. Blood samples from 14 wild and 14 captive condors were analyzed primarily for Pb. Five of 14 wild condors sampled had elevated (> 0.70 ppm) concentrations of Pb in blood whereas Pb concentrations in all captive condors were low. Lead levels in individual birds often fluctuated over time. Lead exposure, especially poisoning, was a major factor affecting the wild California condor population during 1982-86. The probable source of Pb was bullet fragments in carrion on which condors were feeding.

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Journal of Wildlife Management Article

Source-reported bounding extent: 32.534156° to 42.009247° latitude; -124.409591° to -114.134768° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Stanley N. Wiemeyer, J. Michael Scott, Marilyn P. Anderson, Peter H. Bloom, Charles J. Stafford. 1988. Environmental contaminants in California condors. https://doi.org/10.2307/3801228

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