Post on 22-Jan-2018
transcript
The State of the Science: What Oyster Related Tools Do We/Could We Have?
Suzanne Bricker and Chris Moore
Virginia Oyster Restoration Workshop Brock Environmental Center
Virginia Beach, VAMay 2, 2017
Chesapeake Bay Program Partnership Water Quality Assurance Process
Best Management PracticesCBP-approved practices or technologies are approved for credit toward achieving
WIP commitments
Watershed Implementation Plan
States and local partners develop plans to achieve
pollutant reductions
ChesBay TMDL / ModelA plan was developed to
reduce nitrogen, phosphorus, and sediment loads.
End Goal: Meet Water
Quality Standards
Water Quality Assessment2010 Chesapeake Bay did not meet
nitrogen, phosphorus, and sediment water quality standards
Nutrients cause water quality degradation:Too much of a good thing
Potomac River, MD
Florida Bay, FLCaloosahatchee Bay, FL
Corsica River, MD
Excessive algal blooms
Low dissolved oxygen fish kills
Harmful Algal Blooms
Loss of seagrasses due to loss of light penetration
Qiangdao, China
What is a Best Management Practice?
BMPs are practices / technologies used by the Chesapeake Bay Partnership to reduce nutrient pollution to help meet water quality goals.
• Structural BMP: runoff diversions, silt fence, stream buffers, groundcover vegetation, and oysters!
• Non-structural / programmatic BMP: preharvest planning/nutrient application management, manure transport, stormwater management.
Approved BMPS are given ‘credits’ for the amount of nutrients they remove.
BMPS are tools for nutrient reductions
Why the interest in nutrient BMPs?65% of US estuaries have moderate to high level degradation
from nutrients
From: Bricker et al. 2007. Effects of Nutrient Enrichment in the Nation’s Estuaries: A Decade of Change, National Estuarine Eutrophication Assessment Update
• Biological removal of nutrients directly from the water through filtration by shellfish, removes algae and particulates – improves water quality
Oysters as BMPs?
Eastern Oyster,Crassostrea virginica Source: Screenshots from Chesapeake Bay
Foundation time-lapsed video of a reef
Filter Feeders Influence Water Quality
The Stars of our Show: The Mighty Bivalve
Eastern Oyster, Crassostrea virginica Northern Quahog
Mercenaria mercenaria
Ribbed MusselGeukensia demissa
Blue MusselMytilus edulis
Geoduck clamPanopea generosa
Sampling on Chesapeake MD oyster farms providing water quality data and oysters
Map of oyster aquaculture study sites in Maryland
Ongoing study (Parker and Bricker) to estimate the ecosystem service of
(potential) nutrient removal capability of oysters, and the value represented by
the service being provided by oysters
Site 6
Single oyster bottom cage
Single oyster floating cage
Spat on shell bottom
Previous studies
Study sites
Research to help determine oyster related nutrient removal at local scale
Current Current
Width
DepthChl a
POM
Chl a
POM
Sections
1 2 3 n-1 n
Finfish, shellfish, algae
POM
(Ferreira et al., 2007)
algaealgae
particulates particulates
particulates
Models for a single oyster farm estimate production and nutrient removal
Parker and Bricker data used to calibrate to Chesapeake Bay
Simulations to determine potential impact of oyster reef and
aquaculture removal of nutrients in the entire waterbody
Shows feasibility and potential for using oysters as BMP
Research to determine impact of oyster nutrient removal at waterbody scale
System Wide Eutrophication Model2300 boxes
EcoWin2000 grid42 boxes
ApprovedConditionalRestrictedProhibited
Chesapeake Bay13,000 boxes
Long Island Sound
Oyster Calculator: A tool developed from research and modeling
http://oceanwealth.org/tools/oyster-calculator/
Determines water filtration based on area of reef, size and density of oysters. Determines associated fish production.Current conditions and desired conditions – set goals
Oyster reef restoration(want to add aquaculture
of oysters and kelp)
James River, VAJames River, VA
Using bivalve shellfish to improve water quality
Chesapeake Bay Partnership Program convened Oyster BMP Expert Panel in 2015
Best Management PracticesCBP-approved practices or technologies are approved for credit toward achieving
WIP commitments
Watershed Implementation Plan
States and local partners develop plans to achieve
pollutant reductions
ChesBay TMDL / ModelA plan was developed to
reduce nitrogen, phosphorus, and sediment loads.
End Goal: Meet Water
Quality Standards
Water Quality Assessment2010 Chesapeake Bay did not meet
nitrogen, phosphorus, and sediment water quality standards
Oyster BMP Expert PanelEvaluates reduction
effectiveness of proposed BMPs following the CBP
BMP Review Protocol
Oyster nutrient and sediment removal processes under evaluation
1.Tissue and shell nutrient content 2.Denitrification rates associated with oyster reefs 3.Burial in sediment
•First focus was nutrients removed via tissue of oysters harvested from private oyster aquaculture practices.
•Panel reviewed existing studies and data to determine tissue nitrogen and phosphorus content.
•Panel review continues.
Oyster BMP Expert Panel First Recommendations released December 19,
2016 • Decision framework illustrating the process by which nutrient removal recommendations will be generated.
• Recommended amounts of nutrient removal to be credited by the Chesapeake Bay Program for oyster tissue:
• Off-bottom private oyster aquaculture using hatchery-produced oysters
• On-bottom private oyster aquaculture using hatchery-produced oysters
• On-bottom private oyster aquaculture using substrate addition
(Under discussion whether reefs will be allowed credits)
• Derived from oyster growth data from Chesapeake Bay locations.• Determined five size class ranges based on shell height.
The Panel also recommended a methodology to determine site-specific estimates.
BMP NameLbs N Reduced/ millionmillion Oysters
Harvested
Lbs P Reduced/ millionmillion Oysters
Harvested
Diploid Oyster Aquaculture 2.25 Inch 110 22
Diploid Oyster Aquaculture 3.0 Inch 198 22Diploid Oyster Aquaculture 4.0 Inch 331 44
Diploid Oyster Aquaculture 5.0 Inch 485 44Diploid Oyster Aquaculture ≥ 5.5 Inch 683 66
Triploid Oyster Aquaculture 2.25 Inch 132 22Triploid Oyster Aquaculture 3.0 Inch 287 22Triploid Oyster Aquaculture 4.0 Inch 573 66
Triploid Oyster Aquaculture 5.0 Inch 970 110Triploid Oyster Aquaculture ≥ 5.5 Inch 1,477 154
Recommended Default Estimates for Nutrient Credits
Triploid oysters have greater nutrient tissue content than diploid oysters of same shell height because they have greater tissue biomass.
What does this mean for water quality management programs ?
• Research and sampling support development and improvement of tools for successful water quality management
• States can now use harvested oyster tissue from aquaculture as a nutrient BMP in Watershed Implementation Plans, can pursue inclusion in nutrient trading programs
• Models (FARM, Chesapeake Bay Model, Oyster Calculator) for predicting ecosystem services currently and with increased aquaculture production or area of restored reefs – assists setting restoration goals and forecasting results
• Oyster Calculator to be expanded for use in oyster related nutrient restoration – reefs and farms
Acknowledgements – Thank You!!
• Don Webster and organizers of
Watermen’s Trade Show seminar
• Chesapeake Bay Partnership
• Oyster Recovery Partnership – Julie
Reichert and Ward Slacum
• Jeffrey Cornwell and other Oyster BMP
Panel Members
• Julie Rose, NOAA NMFS Milford Lab
• Oyster growers who contribute to research