Exposure and Effects Pilot Study Small Fish Mercury Project Ben Greenfield 1, Letitia Grenier 1, Andrew Jahn 2, Seth Shonkoff 1, Mark Sandheinrich 3, Joy Andrews 4, Jay Davis 1 1. SFEI; Riverside Drive, Ukiah, CA; 3. River Studies Center, University of Wisconsin – La Crosse; 4. California State University – East Bay

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

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

Design Design Four composites per species per site - allow statistical comparison Four composites per species per site - allow statistical comparison 5-10 individuals/composite 5-10 individuals/composite Minimize covariates by using consistent sizes Minimize covariates by using consistent sizes EEPS Small Fish Hg Project

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

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

3

Treatment Reference Bay Goby

Preliminary Results 72 Composite samples analyzed 72 Composite samples analyzed Data received last week Data received last week QA was good QA was good 94% recovery of spiked samples 94% recovery of spiked samples 5% relative standard deviation of triplicate samples 5% relative standard deviation of triplicate samples

Pelagic Species Higher

Spatial Patterns Alviso Slough Newark Slough Bird Island Eden Landing Oakland Middle Harbor China Camp Benicia Park

Comparison to Fish/Wildlife Risk Thresholds * Tissue concentration dry weight

Summary Variation among species Variation among species Mississippi Silverside > Topsmelt > Arrow/Cheekspot Gobies > Bay Goby Mississippi Silverside > Topsmelt > Arrow/Cheekspot Gobies > Bay Goby Variation among stations Variation among stations Alviso Slough generally elevated Alviso Slough generally elevated Southern stations elevated in silversides (Alviso, Newark, Bird Island) Southern stations elevated in silversides (Alviso, Newark, Bird Island)

Future Steps Evaluate species selection Evaluate species selection Are we on the right track with chosen species? Are we on the right track with chosen species? Evaluate sample sizes and study design Evaluate sample sizes and study design Power analysis Power analysis Estimate wildlife risk Estimate wildlife risk Long-term trend evaluation Long-term trend evaluation

Thanks to… April Robinson Bridget Mooney Cindy Patty Darell Slotten Marco Sigala Dave Crane Sarah Cohen Meg Sedlak Joel Baker Arthur Fong SF Bay National Wildife Refuge California State Parks CA Department Fish & Game