R5 PM Avian Sentinels of Environmental Contamination
Thursday, 17 November 2005: 1:50 PM - 5:30 PM in 321-323

(STR-1117-657431) Great blue heron at Crab Orchard National Wildlife Refuge: Exposure and effects of polychlorinated biphenyls (PCBs).

Straub, C¹, Halbrook, R¹, Lydy, M¹, ¹ Southern Illinois University, Carbondale, Illinois, United States

ABSTRACT- Crab Orchard National Wildlife Refuge (CONWR) is located in southern Illinois; it is used as a refuge, and for recreation, agriculture, and industrial activities including munitions manufacturing. Previous electrical industrial activities at CONWR resulted in polychlorinated biphenyl (PCB) contamination. In 1987, CONWR was placed on the National Priorities List, and the 1990 Record of Decision provided for remediation of PCBs by excavation and incineration of soils and sediments; however, sediments at the east end of Crab Orchard Lake (COL) remain contaminated (Aroclor 1254 ranged between 15 to 690 ppb) and remediation decisions are ongoing. It is important to determine if there is risk to wildlife at CONWR resulting from exposure to PCB contaminated sediments. The objective of the current study includes evaluating two great blue heron (GBH) (Ardea herodias) rookeries, located near COL, to determine accumulation and reproductive effects of PCBs. One colony is located at the east end of the lake, near areas where elevated concentrations of PCBs have been reported in sediment and fish. The other colony is located on the west end of the lake and is not thought to be exposed to PCBs. The number of eggs laid and the number of chicks surviving two plus weeks were recorded to determine reproductive success. No significant difference (P≤0.05) in reproductive success between the rookeries was observed. Polychlorinated biphenyl concentrations were measured in eggs, fat tissue collected from chicks, gizzard shad (Dorosoma cepedianum), the dominant fish species consumed by heron, and regurgitate collected at each colony. This presentation reports PCB results and evaluates risk of PCBs to a piscivorous avian species at CONWR. These results provide valuable information for remedial decisions and management of the refuge.

Key words: polychlorinated biphenyls, great blue heron (Ardea herodias), Crab Orchard National Wildlife Refuge