Evaluation of shellfish aquaculture and Evaluation of shellfish aquaculture and nutrient removal and credit trading in nutrient removal and credit trading in

Long Island SoundLong Island Sound

Estuarine & Coastal Sciences Association: ECSA47 SymposiumFigueira da Foz, PortugalSeptember 14-19, 2010

Suzanne Bricker NOAA National Ocean ServiceJoao Ferreira IMARKatharine Wellman Northern EconomicsGary Wikfors NOAA National Marine Fisheries ServiceMark Tedesco EPA Long Island Sound StudyJulie Rose NOAA National Marine Fisheries ServiceBob Rheault East Coast Shellfish Growers

AssociationRobin Landeck Miller HydroQualPaul Mankiewicz The Gaia Institute

Long Island Sound: Background

ConnecticutConnecticut

New York New York

Size: 3,259 km2 Tide: 2 m in west, 1 m in eastResidence time: 2-3 monthsHighly developed watershedPopulation: 4.9 x 106 total, 1,508 people/km2

2/3 freshwater inflow from Connecticut River

• Nutrients and hypoxia - eutrophication • Toxic Contaminants and pollution• Pathogens• Floatable debris

The Long Island Sound Study names 4 major water quality issues being addressed by government agencies, environmental groups, universities and the private sector:

EPA Regional Ecosystem Services Program– EPA Regional Ecosystem Services Program– Eutrophication and shellfish aquacultureEutrophication and shellfish aquaculture

Two year project, EPA funded, focus on Long Island Sound and Great Bay/Piscataqua region;

Research groups from NOAA, EPA, HydroQual Inc., Longline Environment Ltd., Northern Economics, Shellfish Environmental Services;

Conduct a comparative study on the bioextraction potential of shellfish, and its contribution to ecosystem services;

Species: Eastern oyster, Northern quahog, ribbed mussel;

For Long Island Sound (major case study): combine watershed models, detailed water quality models (SWEM), EcoWin2000, FARM, and economic models.

LIS Eutrophication Impacts

Hypoxia

Loss of eelgrass from historic range

Species shifts (Picture or explanation?)

NEEA/ASSETS Results: LIS Highly Eutrophic

Since early 1990s:Nuisance/toxic blooms improvedNuisance/toxic blooms improved

Macroalgae improvedMacroalgae improvedChl no changeSAV no changeDO worsened

Bricker et al. 2007, Nutrient enrichment in the nation`s estuaries, A decade of change. National Estuarine Europhication Assessment Update. www.eutro.us

Potential Resolution of Nutrient issues:Potential Resolution of Nutrient issues:Long Island Sound TMDL*Long Island Sound TMDL*

(Approved by EPA April 2001)(Approved by EPA April 2001)

In-basin Nitrogen Reduction GoalIn-basin Nitrogen Reduction Goal– 58.5% by 201458.5% by 2014

• 10% reduction to urban and agricultural runoff10% reduction to urban and agricultural runoff• 59-64% reduction to point sources59-64% reduction to point sources

Allows “Trading” of nutrient creditsAllows “Trading” of nutrient credits Out-of-basin ActionsOut-of-basin Actions

– Out of State Sources (10% reduction to runoff, 25% Out of State Sources (10% reduction to runoff, 25% reduction to point sources)reduction to point sources)

– Atmospheric Deposition (Clean Air Act reductions)Atmospheric Deposition (Clean Air Act reductions) Alternatives to nutrient controlAlternatives to nutrient control

– Biomass harvestingBiomass harvesting Periodic Revision (Adaptive Management)Periodic Revision (Adaptive Management)

– Evaluation in 2008Evaluation in 2008

*Total Maximum Daily Load*Total Maximum Daily Load

Potential Resolution of Nutrient issues:Potential Resolution of Nutrient issues:nutrient bioextraction considered for LISnutrient bioextraction considered for LIS

Longtime nitrogen management focus has been point Longtime nitrogen management focus has been point sources (i.e. wastewater treatment plant upgrades)sources (i.e. wastewater treatment plant upgrades)

Growing recognition that non-point source pollution is Growing recognition that non-point source pollution is also a substantial (more difficult) problemalso a substantial (more difficult) problem

Nutrient bioextraction can also address legacy pollution Nutrient bioextraction can also address legacy pollution in the water column and sedimentsin the water column and sediments

International Workshop on Bioextractive Technologies for Nutrient RemediationDecember 3-4, 2009 at UConn Stamford

How does bioextraction work? How does bioextraction work?

• Cultivation and harvest of shellfishshellfish and macroalgae

• Nutrients are taken up directly (seaweed) or indirectly (shellfish, via plankton, organic detritus)

• Removal of biomass removes nutrients from the ecosystem

• Removal of 1ary eutrophication symptoms reduces 2ary symptoms by (i) improving water clarity, restoring SAV; (ii) limiting D.O. loss from decomposition of organic matter

• Shellfish farmers can negotiate nutrient credits to offset loading fom land, and be included in the trading program

Scope of shellfish aquaculture:Scope of shellfish aquaculture:

American Oyster (American Oyster (Crassostrea virginicaCrassostrea virginica), Northern Quahog clam (), Northern Quahog clam (Mercenaria mercenariaMercenaria mercenaria))

Shellfish lease areaHarvest – Bottom Culture

State Approved Restricted Prohibited Total as % total area 103 acres

NY 84 0.2 16 489

CT 51 31 18 444

NY/CT 68 15 17 934

Approved for CT includes conditionally approved, forNY Approved is represented by Certified and Restricted is represented by Seasonal rating.Prohibited (CT) and Uncertified (NY) are considered equal.

LIS Hard Clam harvest

0

200000

400000

600000

1980 1985 1990 1995 2000 2005 2010

C T Harves t

NY Harves t

LIS Oyster Harvest (NY+CT)

0

300000

600000

900000

1200000

1980 1985 1990 1995 2000 2005 2010

LIS Oyster Harvest Value

01020304050

1980 1985 1990 1995 2000 2005 2010

Mill

ions

of D

olla

re

NY only

20 kT

27 kT

On the basis of a yield of 10 tonnes ha-1 (1 kg m-2), the reported harvest of ~17,000 tonnes (37 million lb) would correspond to 17 km2, i.e. ~4200 acres

System-scale ecological modelling

SWEM, E2K, ASSETS

System-scale ecological modelling

SWEM, E2K, ASSETS

Transport model

SWEM

Transport model

SWEM

Individual growth models for cultivated species

Ribbed mussel

Individual growth models for cultivated species

Ribbed mussel

Farm-scale modelling

FARM model

Farm-scale modelling

FARM modelCatchment

model

SPARROW, Watershed

Runoff Modelling

Catchment model

SPARROW, Watershed

Runoff Modelling

System- and local-scale ecological

modelling

E2K, FARM, ASSETS

System- and local-scale ecological

modelling

E2K, FARM, ASSETS

Field measurements

Field measurements

In situ and lab experiments

In situ and lab experiments

Public participation

Public participation

Economic modelMillennium Ecosystem

Assessment Framework

Economic modelMillennium Ecosystem

Assessment Framework

The REServ approachThe REServ approach

Preliminary simulations of biomass harvesting Preliminary simulations of biomass harvesting show substantial DO improvements show substantial DO improvements

Phase 3 & 4 TMDL: N & Corg

With shellfishand seaweeds

Change in dissolved oxygen through the use of IMTA

System-Wide Eutrophication model (SWEM) HydroQual, 2009. Model year simulation: 1988

4.0

3.0

2.0

1.0

0.0

+4.0

+2.0

0.0

-2.0

-4.0

Min

imu

m D

.O (

mg

L-1)

De

lta

min

.D.O

(m

g L

-1)

Data Drivers for simulated farmData Drivers for simulated farm

Simulated farm location from CTDEP aquaculture bottom lease maps and CTDEP

data for station 09 for drivers of FARM

Salinity

22

24

26

28

30

J F M A M J J A S O N D

Water temperature (deg C)

05

10152025

J F M A M J J A S O N D

Simulated farm location is within approved lease areas

Data for Station 09 for 2008Thanks to Matt Lyman of CTDEP

Data Drivers for FARM model applicationData Drivers for FARM model application

Station 09 for 2008Station 09 for 2008

Chlorophyll (ug/l)

05

10152025

J F M A M J J A S O N D

Particulate carbon (mg/l)

0.0

0.5

1.0

J F M A M J J A S O N D

TSS (mg/l)

0

10

20

30

40

J F M A M J J A S O N D

Dissolved oxygen (mg/l)

0

5

10

15

J F M A M J J A S O N D

Preliminary FARM model resultsPreliminary FARM model results

Total N load to LIS = 50 x103 t y-1

Summary and ConclusionsSummary and Conclusions

• Biomass harvesting – • promising solution to nutrient issues • complementary to land-based nutrient load reductions• provides shellfish product, income for shellfish farmers• caveat: marine spatial planning

• Significance to LIS nutrient budget not known but -• 45 tons N removed in one 10 hectare farm (PEQ 13,600)• Shellfish cultivation in 3% LIS area would remove

equivalent of present N load

• If significant, will shellfish farmers become part of the LIS nutrient trading program?

• Stay tuned

Try the models yourself:FARM www.farmscale.org ASSETS www.eutro.org/register