Southeast Watershed Alliance Symposium Portsmouth, New Hampshire, 11 May 2011 Oyster Restoration, Aquaculture, and Bioextraction in New Hampshire Ray Grizzle Jackson Estuarine Laboratory & Department of Biological Sciences University of New Hampshire,

Status of natural oyster populations Restoration of natural reefs The aquaculture/restoration connection Oyster farming in New Hampshire Nitrogen bioextraction by farmed oysters Presentation Overview

Status of Natural Oyster Populations (Data from NH Fish & Game Department; graphics from Phil Trowbridge, PREP)

The 2006 Recruitment

General Oyster Reef Restoration Protocol in NH Identify restoration site: site survey, consultations with stakeholders, etc. Design restoration project: shell “planting,” remote setting/spat-on-shell production, nursery grow-out, “spat seeding,” Secure permits from relevant regulatory agencies Purchase, arrange for delivery of needed materials: dead mollusc shells, oyster larvae, etc. Secure contracts with marine construction company, other subcontractors Do restoration work (if you have time/energy/$ left)…

General Oyster Reef Restoration Protocol in NH (1) Construct reef base using dead/seasoned mollusc shell: 100% cover of 1 acre requires ~100 yd 3 of shell minimum Subcontract to marine construction company typically required General method shown above

General Oyster Reef Restoration Protocol in NH (2) “Seed” reef base with spat-on-shell from remote setting of oyster larvae

Summary of NH Oyster Restoration Projects Restoration Site, SizeRestoration MethodsSpecies Involved Construction DateSuccess Metrics Last Observation DateGeneral Condition at Last Sampling Salmon Falls River, 0.1 acreadult transfer, spat-on-shellCrassostrea virginica2000 shellfish density & size; water filtration2007 high oyster density from 2006 natural spat set South Mill Pond, 0.05 acreadult transfer, spat-on-shell Crassostrea virginica; Mytilus edulis2001 shellfish density & size; water filtration2007~100% mortality of mussels and oyster Adams Point (Great Bay), 0.05 acregravel base, spat-on-shellCrassostrea virginica2003shellfish density & size2006 heavy silt accumulation; ~100% oyster mortality Nannie Island (Great Bay), 2.5 acresgravel base, spat-on-shellCrassostrea virginica2004shellfish density & size2006 high oyster density from 2006 natural spat set Bellamy River, 1.55 acresadult transfer, spat-on-shell Crassostrea virginica; Mytilus edulis shellfish density & size2008 moderate oyster density from 2006 natural spat set; 100% mussel mortality Nannie Island (Great Bay), 1.5 acresspat-on-shellCrassostrea virginica2007 shellfish density & size; resident plants and animals2009 ~80% spat mortality; high density from 2006 natural spat set Oyster River (TNC), 0.2 acreshell planting, spat-on-shellCrassostrea virginica2009shellfish density & size2009substantial 2009 natural spat set Berry's Brook, 1.0 acreshell planting, spat-on-shellCrassostrea virginica2009 shellfish density & size; water filtration; associated animals2009high spat mortality Oyster River (TNC), 1.0 acreshell planting, spat-on-shellCrassostrea virginica2010shellfish density & size2010(early post-construction obersations only) Oyster River (NRCS/GSS), 1.0 acreshell planting, spat-on-shellCrassostrea virginica2010shellfish density & size2010(early post-construction obersations only) Little Bay (NRCS/LBOC), 1.0 acreshell planting, spat-on-shellCrassostrea virginica2010shellfish density & size2010(early post-construction obersations only)

HISTORIC Funding Sources for Oyster Restoration Piscataqua Region Estuaries Partnership US Environmental Protection Agency National Oceanic & Atmospheric Admin. Cooperative Institute for Coastal and Estuarine Environmental Technology National Estuarine Research Reserve System New Hampshire Sea Grant The Nature Conservancy City of Dover Natural Resources Conservation Service Natural Resources Conservation Service

The Aquaculture/Restoration Connection Rationale: oyster farmers know how to raise oysters… USDA/NRCS funded restoration of 3 acres of bottom area in NH in 2010; a 0.5-acre project is scheduled for 2011 The future?

Existing Oyster Farms in New Hampshire

Secure maps or data needed to produce maps Produce maps of major factors affecting shellfish farming Interview stakeholders Assess all relevant environmental information in context of social factors Assist prospective farmers Interface with regulatory and management agencies Determining the Potential for Expansion of Oyster Aquaculture in New Hampshire

Mapping the Major Factors Maximum PSP toxicity values in estuaryBathymetry, eelgrass, shellfish closures

Interpreting the Maps Map overlay method assesses multiple factors Potential aquaculture areas = adequate depth + open for harvesting + no eelgrass (+ or - other factors)

Nitrogen bioextraction by farmed oysters Two age/size classes (0 year, 1 year) deployed at 6 sites Deployed off-bottom in oyster bags typical for NE Variables: shell height, soft tissue DW, %N, %C CHN/O elemental analyzer (USEPA, Narragansett, RI) ANOVAs on dependent variables

Results

Soft TissueShellWhole Oyster Shell Height (mm) Shell DW (g) Soft Tissue DW (g)%C%N%C%NTotal C (g)Total N (g)Source 7.8n/d n/d Present study 12.7n/d n/d Present study 35.7n/d n/d 0.585*0.013*Present study 55.6n/d n/d 3.082*0.065*Present study n/d 7 0.3n/d0.52Newell et al Higgins et al Higgins et al Higgins et al Higgins et al. 2011

Some ‘what/if’ Scenarios Today: 10 acres, 200,000 oysters/ac/yr, 0.3 g N/oyster: 0.67 ton N The Future?: 50 acres  3.4 tons N/yr 100 acres  6.8 tons N/yr

What factors are involved in estimating the nitrogen bioextraction potential for farmed oysters in NH? Present: Three farms, <100,000 oysters sold in 2010 Future: How many farms can be permitted in NH? What is maximum farm production? How do we accurately quantify bioextraction? What role(s) should oyster farming play?

Next Steps 2011/2012 USEPA-funded study 1-yr deployment, multiple sites, etc Completion of NOAA/NMFS-funded study Assessment of shellfish aquaculture expansion potential Ongoing management/regulatory process ?????