W2 AM Chesapeake Bay Restoration (Part 1)
Wednesday, 16 November 2005: 8:00 AM - 11:40 AM in Ballroom 2

(RAT-1117-053295) Environmental Contaminant Exposure, Effects, and Ecotoxicological Research Needs for Chesapeake Bay Wildlife.

Rattner, Barnett¹, McKernan, Moira¹, Ackerson, Betty¹, McGowan, Peter², ¹ USGS-Patuxent Wildlife Research Center, Beltsville, MD, USA² Chesapeake Bay Field Office, U.S. Fish and Wildlife Service, Annapolis, MD, USA

ABSTRACT- Environmental contamination in Chesapeake Bay ranges from a moderate to potentially significant stressor on waterbirds and terrestrial wildlife. A search of the Contaminant Exposure and Effects-Terrestrial Vertebrates database (www.pwrc.usgs.gov/contaminants-online) revealed 839 data records for terrestrial vertebrates in the Chesapeake Bay region. Recent studies in waterfowl, terns, herons, and ospreys indicate that legacy organochlorine contaminants have declined in eggs and tissues, although p,p'-DDE, total PCBs and coplanar PCB congeners still exert sublethal and reproductive effects in parts of the Bay. Contemporary contaminants (alkylphenols, ethoxylates, perfluorinated compounds, polybrominated diphenyl ethers) are detectable in osprey eggs from regions of concern (Anacostia River, Elizabeth River, Baltimore Harbor) but interpretation of these exposure data are difficult because adverse effect levels are unknown in wildlife. With the possible exception of Cd, concentrations of other metals (e.g., Hg, Pb and Se) in tissues and eggs are below toxic effect thresholds of waterbirds. Since 1990, two moderate-sized oil spills have occurred resulting in the death of several hundred birds; records of the U.S. Fish and Wildlife Service and the U.S. Coast Guard indicate that about 500 smaller spill events occur annually in the Chesapeake Bay region. Exposure and potential effects of dioxins, dibenzofurans, cholinesterase-inhibiting pesticides, rodenticides, and lead shot have not been adequately assessed in the past 15 years, and relatively little is known about impacts of algal toxins on waterbirds in the Bay. In addition, future ecotoxicological research and monitoring activities should focus on amphibians and reptiles throughout the region, and avian species in upper bay tributaries.

Key words: Chesapeake Bay, Wildlife