Mercury in San Francisco Bay forage fish 1 2 3
نویسندگان
چکیده
23 In the San Francisco Estuary, management actions including tidal marsh restoration could 24 change fish mercury (Hg) concentrations. From 2005 to 2007, small forage fish were 25 collected and analyzed to identify spatial and interannual variation in biotic 26 methylmercury (MeHg) exposure. The average whole body total Hg concentration was 27 0.052 µg g-1 (wet weight) for 457 composite samples representing 13 fish species. MeHg 28 constituted 94% of total Hg. At a given length, Hg concentrations were higher in 29 nearshore mudflat and wetland species (Clevelandia ios, Menidia audens, and Ilypnus 30 gilberti), compared to species that move offshore (e.g., Atherinops affinis and 31 Lepidogobius lepidus). Gut content analysis indicated similar diets between Atherinops 32 affinis and Menidia audens, when sampled at the same locations. Hg concentrations were 33 higher in sites closest to the Guadalupe River, which drains a watershed impacted by 34 historic Hg mining. Results demonstrate that despite differences among years and fish 35 species, nearshore forage fish exhibit consistent Hg spatial gradients. 36 37 Capsule: Total mercury in estuarine forage fish varies with species, habitat, and 38 proximity to a historic mercury mine 39 40 Keywords 41
منابع مشابه
Seasonal and annual trends in forage fish mercury concentrations, San Francisco Bay.
San Francisco Bay is contaminated by mercury (Hg) due to historic and ongoing sources, and has elevated Hg concentrations throughout the aquatic food web. We monitored Hg in forage fish to indicate seasonal and interannual variations and trends. Interannual variation and long-term trends were determined by monitoring Hg bioaccumulation during September-November, for topsmelt (Atherinops affinis...
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Pollution reduction efforts should be targeted toward those sources that result in the highest bioaccumulation. For mercury (Hg) in estuaries and other complex water bodies, carefully designed biosentinel monitoring programs can help identify predictors of bioaccumulation and inform management priorities for source reduction. This study employed a probabilistic forage fish Hg survey with hypoth...
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Industrialized waterways frequently contain nearshore hotspots of legacy polychlorinated biphenyl (PCB) contamination, with uncertain contribution to aquatic food web contamination. We evaluated the utility of estuarine forage fish as biosentinel indicators of local PCB contamination across multiple nearshore sites in San Francisco Bay. Topsmelt (Atherinops affinis) or Mississippi silverside (M...
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