Mercury Monitoring and Mercury Monitoring and Assessment in the Assessment in the

South BaylandsSouth BaylandsLetitia Grenier, Joshua Collins, Jay Davis — Letitia Grenier, Joshua Collins, Jay Davis —

SFEISFEIMark Marvin-DiPasquale — USGSMark Marvin-DiPasquale — USGS

David Drury — Santa Clara Valley Water David Drury — Santa Clara Valley Water DistrictDistrict

Peter LaTourette

South Bay Salt Pond South Bay Salt Pond Restoration Hg MonitoringRestoration Hg Monitoring

GoalsGoals Identify areas where Hg is a problem or may Identify areas where Hg is a problem or may

become one for the South Bay Salt Pond become one for the South Bay Salt Pond Restoration ProjectRestoration Project

Study how Hg processes differ between problem Study how Hg processes differ between problem areas and non-problem areasareas and non-problem areas

Collaborative ProjectCollaborative Project SFEI – Letitia Grenier, Josh Collins, Jay DavisSFEI – Letitia Grenier, Josh Collins, Jay Davis USGS Menlo Park – Mark Marvin DiPasqualeUSGS Menlo Park – Mark Marvin DiPasquale SCVWD – Dave DrurySCVWD – Dave Drury

Wetland Tracker is a web-based Eco Atlas tool

Sentinel Species ApproachSentinel Species Approach

Direct measurement of Hg problemDirect measurement of Hg problem MethylmercuryMethylmercury Food web Food web wildlife, people wildlife, people

Integrate over appropriate spatial and Integrate over appropriate spatial and temporal scalestemporal scales Measure the spatial and temporal variation of Measure the spatial and temporal variation of

interest (not very fine-scale variation)interest (not very fine-scale variation)

Link to water/sediment to understand Link to water/sediment to understand processesprocesses

Habitat basedHabitat based One sentinel species per habitatOne sentinel species per habitat

Year-round residentsYear-round residents Small home rangeSmall home range Abundant and important role in food webAbundant and important role in food web

Spatially associated with abiotic Spatially associated with abiotic measurementsmeasurements Water and sediment measurements Water and sediment measurements

spatially mapped onto sentinel species spatially mapped onto sentinel species sampling plansampling plan

Sentinel Species Hg Sentinel Species Hg MonitoringMonitoring

13C

-24 -22 -20 -18 -16 -14

15 N

10

11

12

13

14

15

16

17

Sparrow

Goby

Marsh Plain Foods

Low Marsh Foods

Tidal Channel Foods

cordgrassgum plant

pickleweed

SLOUGH

MARSH PLAINLOW

MARSH

cordgrassgum plant

pickleweed

SLOUGH

MARSH PLAINLOW

MARSH

Grenier 2004

Habitat-specific Sentinel Habitat-specific Sentinel SpeciesSpecies

Sentinel Species MonitoringSentinel Species Monitoring

Salt PondTidal Marsh

Geographically broad sampling to place each restoration site in context.

Need to monitor and assess Baylands, not just salt ponds.

ResultsResults

Identify problem areas by geographyIdentify problem areas by geography e.g., Hg is a greater problem in the Alviso area e.g., Hg is a greater problem in the Alviso area

than near the Island Pondsthan near the Island Ponds

Identify problem areas by habitatIdentify problem areas by habitat e.g., biota in tidal marsh pannes have higher e.g., biota in tidal marsh pannes have higher

Hg than in managed pondsHg than in managed ponds implications for restoration designimplications for restoration design

Increase understanding of Hg processesIncrease understanding of Hg processes e.g., higher Hg in biota is associated with e.g., higher Hg in biota is associated with

habitats that undergo many wetting/drying habitats that undergo many wetting/drying cyclescycles

Phased ApproachPhased Approach

Phase 1Phase 1 Develop sentinel species indicators of Hg Develop sentinel species indicators of Hg

exposure;exposure; Map the legacy Hg in Alviso Slough that might be Map the legacy Hg in Alviso Slough that might be

mobilized by breaching Pond A8 (coring); mobilized by breaching Pond A8 (coring); Use sentinel species coupled with water and Use sentinel species coupled with water and

sediment sampling to assess the mercury sediment sampling to assess the mercury problem for dominant specific habitat types problem for dominant specific habitat types associated with Pond A8 and Alviso Slough;associated with Pond A8 and Alviso Slough;

Establish a baseline for tracking the effects of Establish a baseline for tracking the effects of management actions on the Hg problem into the management actions on the Hg problem into the future. future.

Phased ApproachPhased Approach

Phase 2Phase 2 Expand the survey of the mercury using the Expand the survey of the mercury using the

sentinel species to encompass more of the sentinel species to encompass more of the South Baylands;South Baylands;

Provide a picture of the spatial variability in Provide a picture of the spatial variability in mercury problem within and between bayland mercury problem within and between bayland habitats throughout the South Bay.habitats throughout the South Bay.

Scott Haefner Scott Haefner

Phased ApproachPhased Approach

Phase 3Phase 3 Initiate focused research to better understand Initiate focused research to better understand

the linkages between Hg contamination in the linkages between Hg contamination in sentinel species and bio-geochemical sentinel species and bio-geochemical indicators for specific habitat types in selected indicators for specific habitat types in selected areas, based upon the results of Phase 2; areas, based upon the results of Phase 2;

Help translate the scientific understanding of Help translate the scientific understanding of the Hg problem into habitat designs and the Hg problem into habitat designs and management options that minimize the management options that minimize the problem.problem.

Timeline (Phase 1)Timeline (Phase 1)

Fieldwork: May-Oct 2006Fieldwork: May-Oct 2006

Lab turn-around time: 3-6 monthsLab turn-around time: 3-6 months

Preliminary results: Early 2007Preliminary results: Early 2007

Gillichthys mirabilis Grenier 2001

AcknowledgementsAcknowledgements

Funding SourcesFunding Sources Santa Clara Valley Water DistrictSanta Clara Valley Water District State Coastal CommissionState Coastal Commission San Francisco Foundation Bay FundSan Francisco Foundation Bay Fund Regional Monitoring Program for Regional Monitoring Program for

Trace SubstancesTrace Substances

SBSP Project Management Team SBSP Project Management Team and Science Teamsand Science Teams

Scott Haefner