Mercury in Biosentinel Fish Mercury in Biosentinel Fish in San Francisco Bayin San Francisco Bay

Ben GreenfieldBen Greenfield11, Andrew Jahn, Andrew Jahn22, , Letitia GrenierLetitia Grenier11, Mark Sandheinrich, Mark Sandheinrich33

1. San Francisco Estuary Institute, Oakland, CA1. San Francisco Estuary Institute, Oakland, CA2. 1000 Riverside Drive, Ukiah, CA2. 1000 Riverside Drive, Ukiah, CA

3. River Studies Center, University of Wisconsin – La Crosse3. River Studies Center, University of Wisconsin – La Crosse

Key Management QuestionsKey Management Questions Assessment of ecological risk to fish and Assessment of ecological risk to fish and

wildlifewildlife Spatial and temporal mercury trends in Spatial and temporal mercury trends in

the Estuarythe Estuary Is risk of mercury exposure spatially variable, Is risk of mercury exposure spatially variable,

and are these risks predictable?and are these risks predictable? What are trends in bioaccumulation of Hg vs. What are trends in bioaccumulation of Hg vs.

wetland restoration and TMDL activities wetland restoration and TMDL activities Building upon conceptual models of Hg Building upon conceptual models of Hg

exposureexposure

Multiple sites in San Francisco Bay Multiple sites in San Francisco Bay marginsmargins Wetland restorations vs. extant marshesWetland restorations vs. extant marshes

Benthic and pelagic speciesBenthic and pelagic species Topsmelt, Mississippi (inland) silversidesTopsmelt, Mississippi (inland) silversides Arrow and cheekspot gobyArrow and cheekspot goby

Additional collection in Bay shoals and Additional collection in Bay shoals and channelschannels Bay goby, herring, anchovy (IEP Bay Bay goby, herring, anchovy (IEP Bay

Study)Study)

Sampling DesignSampling Design

Compositing DesignCompositing Design

5-10 individuals 5-10 individuals per compositeper composite

4 composites per 4 composites per species per site to species per site to allow statistical allow statistical comparisoncomparison

Used size limits to Used size limits to reduce influence of reduce influence of any length:Hg any length:Hg relationshipsrelationships

Primary Sampling Primary Sampling LocationsLocations

Alviso Slough

Newark Slough

Bird Island/Steinberger Slough

Eden Landing

China Camp

Benicia Park

Oakland Middle Harbor

Extant Marsh

Restoration AreaPoint Isabel

CandlestickPoint

Opportunistic LocationsOpportunistic Locations

USFWS Survey

Primary Location

IEP Bay Study

Preliminary ResultsPreliminary Results

Results from 97 Results from 97 samples in 2005 and samples in 2005 and preliminary results preliminary results from 114 samples in from 114 samples in 20062006

17 seining locations 17 seining locations and 9 trawling and 9 trawling locations (IEP)locations (IEP)

10 Species10 Species

Inland silversides Animal Diversity Web

Image by Mami Odaya, SFEI

MS

Silv

ersi

de05

MS

Silv

ersi

de06

Top

smel

t05

Top

smel

t06

Anc

hovy

Her

ring

0.00

0.05

0.10

0.15

0.20

0.25

0.30

Patterns among pelagic Patterns among pelagic speciesspecies

Hg w

et

weig

ht

(g/g

)

MS

Silv

ersi

de05

MS

Silv

ersi

de06

Top

smel

t05

Top

smel

t06

Anc

hovy

Her

ring

0.00

0.05

0.10

0.15

0.20

0.25

0.30

Patterns among pelagic Patterns among pelagic speciesspecies

Hg w

et

weig

ht

(g/g

)

TMDL Target for prey fish to protect piscivorous wildlife

Effects threshold for fish (Beckvar et al. 2003)

Patterns among benthic Patterns among benthic speciesspecies

Arr

ow G

oby0

5

Arr

ow G

oby0

6

Che

eksp

ot G

oby0

5

Che

eksp

ot G

oby0

6

Bay

Gob

y05

Bay

Gob

y06

0.00

0.02

0.04

0.06

0.08

0.10

0.12

Hg w

et

weig

ht

(g/g

)

TMDL Target

Conceptual model Conceptual model

Variation among speciesVariation among species Mississippi Silverside > Topsmelt and Mississippi Silverside > Topsmelt and

wetland gobies > Bay Gobywetland gobies > Bay Goby Spatial patternsSpatial patterns

Alviso Slough elevated in cheekspot Alviso Slough elevated in cheekspot gobygoby

South Bay elevated in silversidesSouth Bay elevated in silversides

Arrow Goby

Cheekspot Goby

Bay Goby

Topsmelt Silverside

Be

nth

ic

Pe

lagi

c

Polyhaline wetlands/margins Euhaline Bay open waters Higher Hg in fish Lower Hg in fish (closer to sources/methylation) (hydraulic mixing dilutes MeHg)

AnchovyHerring

Why were arrow and cheekspot Why were arrow and cheekspot gobies higher in 2006?gobies higher in 2006?

Arr

ow G

oby0

5

Arr

ow G

oby0

6

Che

eksp

ot G

oby0

5

Che

eksp

ot G

oby0

6

Bay

Gob

y05

Bay

Gob

y06

0.00

0.02

0.04

0.06

0.08

0.10

0.12

Hg

wet

weig

ht

(g

/g)

Broader size range in 2006Broader size range in 2006

Total length (mm)

15 20 25 30 35 40 45 50 55

Mer

cury

( g

/g w

w)

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

20052006

Arrow goby

Total length (mm)

15 20 25 30 35 40 45 50

Mer

cury

( g

/g w

w)

0.00

0.02

0.04

0.06

0.08

0.10

0.12

20052006

Cheekspot goby

Broader size range in 2006Broader size range in 2006

Comparison to fish/wildlifeComparison to fish/wildliferisk thresholdsrisk thresholds

* Tissue concentration dry weight

Source1. Johnson and Looker 20042. Beckvar et al. 20063. Calculated from BTAG Toxicity Reference Values

Threshold Endpoint # Above % Above0.030 TMDL Target for wildlife (1) 21/46 46%0.200 Fish growth, reproduction, development, behavior (2) 5/211 2%0.130* NOAEL for small sized piscivorous birds (3) 160/211 76%1.440* LOAEL for medium sized piscivorous birds (3) 1/211 0.5%

Spatial PatternsSpatial Patterns

USFWS Survey ‘06

Primary

(Topsmelt)

0 20Miles

Cheekspot goby 2005

Hg

(ug/

g w

et)0.018

0.02

0.022

0.024

0.026

0.028

0.03

0.032

Letters indicate results of ANOVA followed by Student-Newman-Keuls test Station

Alv

iso

Slo

ugh

Ne

wa

rk S

lou

gh

Ed

en

Lan

din

g

Be

nic

ia P

ark

0.00

0.01

0.02

0.03

0.04

b a a a

Hg

wet

weig

ht

(g

/g)

2005 cheekspot goby 2005 cheekspot goby significantly elevated in significantly elevated in Alviso SloughAlviso Slough

Arrow Goby 2006

0 20Miles

Hg

(ug/

g w

et)

0.02

0.03

0.04

0.05

0.06

0.07

0.08 2006 arrow goby 2006 arrow goby

elevated in elevated in southern southern stationsstations

0 20Miles

Mississippi silverside 2005

Hg

(ug/

g w

et)

0.05

0.1

0.15

0.2

Hg

wet

weig

ht

(g

/g)

Mississippi Silverside 2006

0 20Miles

Hg

(ug/

g w

et)

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

2005 silverside 2005 silverside significantly elevated significantly elevated in southern stationsin southern stations

2006 silverside 2006 silverside elevated in elevated in Point IsabelPoint Isabel

0 20Miles

Topsmelt 2005

Hg

(ug/

g w

et)

0.028

0.03

0.032

0.034

0.036

0.038

0.04

0.042

0.044

0.046

0.048

Topsmelt 2006

0 20Miles

Hg

(ug/

g w

et)

0.025

0.03

0.035

0.04

0.045

0.05

0.055

2005 topsmelt elevated 2005 topsmelt elevated in southern stations (not in southern stations (not significant)significant)

2006 elevated in 2006 elevated in southern stations, Pt. southern stations, Pt. Isabel, and TiburonIsabel, and Tiburon

Why are concentrations Why are concentrations often elevated in southern often elevated in southern stations and Pt. Isabel?stations and Pt. Isabel?

Point IsabelPoint Isabel

Urban dump with Urban dump with disposal of car disposal of car batteries and batteries and other metal wasteother metal waste

Enclosed wetland Enclosed wetland with long with long drainage canaldrainage canal Recall conceptual Recall conceptual

model – wetland model – wetland methylationmethylation

Source: Google Earth

Pt. Isabel

Source: Google Earth

Steinberger Slough/Bird Island

China Camp Benicia State Park

Source: Google Earth

Southern Southern stationsstations

RMP data RMP data indicate higher indicate higher sediment MeHg sediment MeHg in southern in southern stationsstations

High sediment High sediment MeHg in Tiburon MeHg in Tiburon

Source: RMP

Results SummaryResults Summary

Some samples above TMDL risk Some samples above TMDL risk threshold for wildlife riskthreshold for wildlife risk

Variation among speciesVariation among species Mississippi silverside > topsmelt, Mississippi silverside > topsmelt,

anchovy, herringanchovy, herring Arrow and cheekspot goby > Bay gobyArrow and cheekspot goby > Bay goby

Spatial patternsSpatial patterns Southern locations higher trendSouthern locations higher trend Pt. Isabel – interior wetlandPt. Isabel – interior wetland

What’s the big picture?What’s the big picture? Variable Variable wildlife riskwildlife risk as a function of target as a function of target

prey and habitatprey and habitat Conceptual modelConceptual model: different exposure in : different exposure in

Bay margins vs. open-water areasBay margins vs. open-water areas Are there more “Point Isabels” throughout the Are there more “Point Isabels” throughout the

Bay?Bay? What drives What drives spatial variationspatial variation? ?

Sources (e.g., historic Hg mining in South Bay Sources (e.g., historic Hg mining in South Bay watershed)watershed)

Net Methyl Hg production in sediments (many Net Methyl Hg production in sediments (many drivers may vary: sulfur, reducing bacteria, drivers may vary: sulfur, reducing bacteria, salinity, water retention time)salinity, water retention time)

Plans for 2007 and Plans for 2007 and beyondbeyond

First year project report availableFirst year project report available ben@sfei.orgben@sfei.org www.sfei.orgwww.sfei.org

Same general sampling design Same general sampling design funded through 2008 – begin funded through 2008 – begin trends analysistrends analysis

Organics analyses in 6 composite Organics analyses in 6 composite samplessamples

Thanks to…April RobinsonAroon MelwaniJohn OramRick WilderSteve SlaterCarrie AustinCollin Eagles-SmithDarell SlottenMax DelaneyFred HetzelMeg SedlakMami OdayaArthur FongSF Bay National Wildlife RefugeUSFWS StocktonUSGS BRDCalifornia State ParksCA Department Fish & GameInteragency Ecological Program

Image by Mami Odaya, SFEI

Total length (mm)

20 40 60 80 100 120

Mer

cury

( g

/g w

w)

0.00

0.02

0.04

0.06

0.08

0.10

20052006

Topsmelt – also no obvious Topsmelt – also no obvious difference between yearsdifference between years

Unpublished data provided by Darell Slotton

Mississippi Mississippi silverside 2005silverside 2005

Combine FMP Combine FMP and RMP dataand RMP data

Results Results indicate indicate highest highest concentrations concentrations in South Bay in South Bay fishfish

This project:This project: Margins of South, Central, and Margins of South, Central, and North BayNorth Bay

Fish Mercury Project: Fish Mercury Project: Central Valley, Delta, Central Valley, Delta, and North Bay – more freshwater focusand North Bay – more freshwater focus

South Bay Salt Pond Hg Project: South Bay Salt Pond Hg Project: Marshes, Marshes, ponds, and sloughsponds, and sloughs

CBDA Bird Hg Project: CBDA Bird Hg Project: Avian forage fishAvian forage fish Petaluma Hg Project: Petaluma Hg Project: Marsh fish in PetalumaMarsh fish in Petaluma Produce comparable data sets by sampling Produce comparable data sets by sampling

same speciessame species

External CoordinationExternal Coordination

Station

Alv

iso

Slo

ugh

New

ark

Slo

ugh

Ste

inbe

rger

Slo

ugh

Ede

n La

ndin

g

Chi

na C

amp

Ben

icia

Par

k

0.00

0.05

0.10

0.15

0.20

0.25

0.30

b b b b a a

Fish vs. SedimentsFish vs. Sediments

Silversides 2005 SedimentSilversides 2005 Sediment

South BaySan PabloBay

Hg w

et

weig

ht

(g/g

)

Station Sal

inity

Tops

mel

t

Silv

ersi

de

Bay

Gob

y

Che

eksp

ot G

oby

Arr

ow G

oby

Shi

mof

uri G

oby

Alviso Slough 23 4 4China Camp 26 4 4Newark Slough 27 2 4 4Eden Landing 29 1 4 4Birds Island 29 2 3 4Oakland Harbor 32 4 4

IEP Treasure Island 4IEP Candlestick 4

Small Fish Hg ProjectSmall Fish Hg Project

3

Station

Alv

iso

Slo

ugh

New

ark

Slo

ugh

Ste

inbe

rger

Slo

ugh

Ede

n La

ndin

g

Chi

na C

amp

Ben

icia

Par

k

0.00

0.05

0.10

0.15

0.20

0.25

0.30

b b b b a a

Topsmelt station vs. mercury

Station

Alv

iso

Slo

ugh

New

ark

Slo

ugh

Ste

inbe

rger

Slo

ugh

Ede

n La

ndin

g

Oak

land

Har

bor

Ben

icia

Par

k

0.00

0.01

0.02

0.03

0.04

0.05

0.06

Hg

wet

weig

ht

(g

/g)

Mississippi Silverside 2005 Topsmelt 2005

Bay gobyBay goby Spatial pattern confounded by fish Spatial pattern confounded by fish

sizesize Try to limit size rangeTry to limit size range

Total length (mm)

20 40 60 80 100 120

Mer

cury

( g

/g w

w)

0.00

0.01

0.02

0.03

0.04

Station

212

106

211

215

214

0.00

0.01

0.02

0.03

0.04

a a b b b

Total length (mm)

24 26 28 30 32 34

Me

rcu

ry ( g

/g w

w)

0.00

0.01

0.02

0.03

0.04

E

E E

EB B

B

BNN N

N

A

AA

A

StationA

lvis

o S

loug

h

New

ark

Slo

ugh

Ede

n La

ndin

g

Ben

icia

Par

k

0.00

0.01

0.02

0.03

0.04

b a a a

Cheekspot gobyCheekspot goby

Topsmelt length vs. mercury

Total length (mm)

30 40 50 60 70 80 90 100 110

Me

rcu

ry ( g

/g w

w)

0.00

0.01

0.02

0.03

0.04

0.05

0.06

O

O

O

OO

OO

OO

E

E

E

S

S

N

N

NN

A

A

BB

Topsmelt station vs. mercury

Station

Alv

iso

Slo

ugh

New

ark

Slo

ugh

Ste

inbe

rger

Slo

ugh

Ede

n La

ndin

g

Oak

land

Har

bor

Ben

icia

Par

k

0.00

0.01

0.02

0.03

0.04

0.05

0.06

Total length (mm)

20 40 60 80 100

Mer

cury

( g

/g w

w)

0.01

0.1

AGAG

AGAGAG

AG

AG

BGBGBG

BG

BGBG

BG

BG

BG BG BG

BGBGBG

BG

BG

BG

BG

BG

BG

CG

CGCG

CGCGCG

CG

CGCGCG CG

CG

CG

CGCGCG

MS

MS

MS

MS

MSMSMS

MS

MS

MS

MS

MS

MS

MS

MS

MSMS

MS

MS

MSMS

MS

MS MS

MS

MS

SGSG

SGSG

SGTS

TS

TS

TSTS

TSTS

TSTS

TS

TSTS

TS

TS

TS

TS

TSTS

TS

TS

TSTSYG

Striped bass Hg concentrations Striped bass Hg concentrations in SF Estuary over timein SF Estuary over time

Year

1970 1971 1972 1994 1997 1999 2000 2003

Mer

cury

Con

cent

ratio

n (

g/g)

0.1

0.2

0.3

0.4

0.5

0.60.70.80.9

1

1.8

1.2

2

1.41.6

For more information on sport fish monitoring, see poster # 27

Small Fish Hg ProjectSmall Fish Hg Project

BackgroundBackground Mercury (Hg) in N. California waters a Mercury (Hg) in N. California waters a

longstanding management concern due longstanding management concern due to historic miningto historic mining

Elevated concentrations in sport fishElevated concentrations in sport fish San Francisco Estuary site of extensive San Francisco Estuary site of extensive

wetland restoration activitywetland restoration activity Sensitive wildlife in regionSensitive wildlife in region

Why Small Fish?Why Small Fish?

Most sport fish over Most sport fish over health advisory health advisory threshold (0.3 ppm)threshold (0.3 ppm)

TMDL has small fish TMDL has small fish targets but there are targets but there are limited data from limited data from BayBay

Contaminant Contaminant pathway to sport pathway to sport fish poorly knownfish poorly known

Effect of extensive Effect of extensive wetland restorationwetland restoration

Hg, ppm wet wt.

0.2

2.0

Ca. h

alib

ut

Jack

smel

t

Leop

ard

shar

k

Shin

er p

erch

Stripe

d ba

ss

Wt. cro

aker

Wt. stu

rgeo

n

Regional Monitoring Regional Monitoring Program Small Fish Project Program Small Fish Project

GoalsGoals Monitor food-web mercury at fine Monitor food-web mercury at fine

spatial and temporal scalesspatial and temporal scales Assess regional trends in Assess regional trends in

bioaccumulation of Hg related to bioaccumulation of Hg related to wetland restorationwetland restoration

Develop conceptual model of Hg Develop conceptual model of Hg availability to prey fishesavailability to prey fishes

Collect prey fish appropriate for Collect prey fish appropriate for wildlife risk evaluationswildlife risk evaluations