Geographical distribution of parasites and pathologies and relationship to contaminant body burden in sentinel bivalves: NOAA status and trends 'Mussel Watch' program.

摘要

The 1995–1998 histopathology data from the NOAA's Mussel Watch Project were used to compare the distribution patterns of parasites among sentinel bivalves collected from the entire U.S. coast. Higher parasite diversity was observed in the eastern oyster, Crassostrea virginica, among host bivalve taxa and on the Gulf coast among locations. Among different bivalve taxa, gill ciliates and trematodes were more common in mytilids ( Mytilus edulis from the East coast, and west coast mytilids, M. californianus, M. galloprovincialis and M. trossulus). Parasite burdens were distinctly lower in the introduced dreissenids ( Dreissena polymorpha and D. bugensis) in the Great Lakes than in marine mytilids or oysters. Within the marine mytilids, pathologies, gill ciliates, trematodes, and nematodes were more common in East coast M. edulis than in the West coast mytilids. Nematodes and Dermo disease were more frequently found in Gulf coast oysters than in East coast oysters.; Locations of most regional boundaries for parasites corresponded well with those of well-known provincial boundaries for free-living coastal animals. Major regional boundaries were Cape Hatteras, Cape Lookout-Cape Fear and Cape Canaveral on the East coast; Tampa Bay, Mississippi River and the southern Texas coast on the Gulf coast; and central California and between Washington and Alaska on the West coast.; The majority of correlations between different types of parasites and pathologies were negative. The only positive associations found were between gill gregarines and cestodes in both East and Gulf oysters; tissue pathologies and gill gregarines in Gulf oysters; tissue pathologies and cestodes in Gulf oysters, and gregarines and Dermo disease in Gulf oysters.; Significant relationships between biological and contaminant variables were more common with metals, common with pesticides and less common with PAHs. High body burdens of Ag, Cu and Zn in oysters were associated with increased weighted prevalences of oyster parasites such as gregarines, MSX and Dermo, whereas higher Pb body burden in mytilids was positively correlated with weighted prevalences of typical trematodes and major pathologies in mytilids. This study also indicates the importance of synergistic effects of multiple contaminants on parasites and pathologies, suggesting complex biological-contaminant interactions.