ABSTRACT
Clear Lake, CA, is a focus ecosystem of the EPA-supported University of California, Davis (UCD), Center for Ecological Health Research. Several Clear Lake fish species carry high levels of methyl mercury (MeHg) in their flesh (Stratton et al., 1987). Mercury (Hg) leaches into the lake from naturally occurring cinnabar ores and from anthropogenic sources such as the Sulphur Bank Mercury Mine, an EPA Superfund site. Hg-contaminated sediments near the abandoned mine from the lake’s Oaks Arm are classified as hazardous waste by the California Department of Health Services. By contact or ingestion, Hg is taken up by aquatic organisms and, presumably, biomagnifies up the lake food web (Watras et al., 1994; Suchanek et al., 1997). The abundant Clear Lake fishes are important components of the food web (Moyle, 1976), but little is known about the fishes’ Hg uptake routes and rates in the ecosystem.
