Potential Hazards of Environmental Contaminants to Avifauna Residing in the Chesapeake Bay Estuary

A search of the Contaminant Exposure and Effects-Terrestrial Vertebrates (CEE-TV) database revealed that 70% of the 839 Chesapeake Bay records deal with avian species. Studies conducted on waterbirds in the past 15 years indicate that organochlorine contaminants have declined in eggs and tissues, although p,p’-DDE, total polychlorinated biphenyls (PCBs) and coplanar PCB congeners may still exert sublethal and reproductive effects in some locations. There have been numerous reports of avian die-off events related to organophosphorus and carbamate pesticides. More contemporary contaminants (e.g., alkylphenols, ethoxylates, perfluorinated compounds, polybrominated diphenyl ethers) are detectable in bird eggs in the most industrialized portions of the Bay, but interpretation of these data is difficult because adverse effect levels are incompletely known for birds. Two moderate-sized oil spills resulted in the death of several hundred birds, and about 500 smaller spill events occur annually in the wat...