Exposure and Effects Pilot Study Small Fish Mercury Project

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Exposure and Effects Pilot Study Small Fish
Mercury Project

• Ben Greenfield, Letitia Grenier, Andrew Jahn,
• Seth Shonkoff, Joy Andrews, Esther Letteny,
• Mark Sandheinrich

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EEPS ? Small Fish Hg Project

• Goals
• Characterize food-web mercury at finer spatial
  and temporal scales than sport fish studies
• Detect regional trends in bioaccumulation of Hg
  related to wetland restoration
• Identify differences in pattern between benthic
  and pelagic food webs

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EEPS ? Small Fish Hg Project

• Design
• 8 sites from South Bay to Suisun Bay
• 4 sites near restoration projects
• 4 index sites near extant marshes
• Additional samples in deep water
• Sample benthic and pelagic species at each site
• Use related types of species to create data sets
  comparable across a wide range of salinities
• Topsmelt/Mississippi (inland) silversides
  (Atherinopsidae)
• Arrow goby, cheekspot, and Shimofuri goby
  (Tridentiger)
• Bay goby from deep water

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EEPS ? Small Fish Hg Project

• Design
• Four composites per species per site - allow
  statistical comparison
• 5-10 individuals/composite
• Minimize covariates by using consistent sizes

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EEPS ? Small Fish Hg Project

• Collaboration and leverage
• Analytical lab - UW LaCrosse River Studies Center
• Additional samples for individual Hg analysis by
  CSU - East Bay (Joy Andrews)
• Extra samples collected using clean techniques
  for trace organics analysis
• Looking for funding for analysis
• Bay Gobies from IEP trawl surveys

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EEPS ? Small Fish Hg Project

• Coordination with other monitoring
• Geographic
• EEPS samples bay edge - South, Central and North
  Bay
• South Bay Salt Pond Hg project samples inside
  marshes, ponds, and sloughs
• CBDA Fish Mercury Project - North Bay, more
  freshwater focus
• Species
• Intent to produce data set as comparable as
  possible across region

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EEPS ? Small Fish Hg Project
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EEPS ? Small Fish Hg Project
Treatment Reference Bay Goby
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EEPS ? Small Fish Hg Project
Treatment Reference Bay Goby