Finkelstein and Bakker find contamination from marine mammals threatening California condors
Biologists have discovered high levels of pesticides and other contaminants from marine mammals in the tissues of endangered California condors living near the coast that they say could complicate recovery efforts for the largest land bird in North America.
"Even though marine mammals are a potentially abundant food source for condors, they might not be that safe to eat" said Carolyn Kurle, an assistant professor of biology at UC San Diego and one of the senior authors of a study published this week in the journal Environmental Science and Technology that found high levels of persistent contaminants in California condors inhabiting the Central California coast when compared to inland condors.
Because marine mammal carcasses can be an abundant food source for coastal scavengers and are thought to have helped prevent the extinction of California condors at the end of the last ice age, 11,700 years ago, biologists welcomed this type of ocean-front dining as a likely boon to the condors' recovery efforts.
But Kurle and the study's two other senior co-authors, Victoria Bakker of Montana State University and Myra Finkelstein of UC Santa Cruz, found that coastal condors had 12- to 100-fold greater mean plasma concentrations of mercury, chlorinated pesticides, polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) than noncoastal populations.