1. Secondary Production of Infaunal Benthic Communities in Chesapeake Bay in Comparison to Restored Oyster Reefs Amanda Lawless and Dr. Rochelle Seitz Virginia Institute of Marine Science, The College of William & Mary Gloucester Point, VA

2. Introduction  Eastern Oyster, Crassostrea virginica Ecologically and commercially important in Chesapeake Bay Ecologically and commercially important in Chesapeake Bay  Over-harvesting, disease, pollution, and loss of habitat have drastically reduced the population  Reef restoration Chesapeake Bay Oyster Harvest (’53-’98)

3. Chesapeake Bay Lynnhaven Bay

4. Chesapeake Bay Atlantic Ocean Western BranchEastern Branch Lynnhaven River Broad Bay Linkhorn Bay Characteristics: Shallow Tidal Influence Temperature: 26-32°C Salinity: 19-24 ppt

5. Objective  To compare the productivity of a lost benthic community to the productivity of oysters on four types of oyster reefs

6. Oyster Reefs Oyster Shell Reef Module Reef Rip Rap Reef Reef Ball

7. Methods  Benthic Sampling Macrofaunal suction (0.11 m 2 area to 40 cm depth) Macrofaunal suction (0.11 m 2 area to 40 cm depth) Four random samples, prior to reef deployment Four random samples, prior to reef deployment  Bivalves Macoma balthica Macoma balthica Tagelus plebeius Tagelus plebeius  Remaining Infauna Estimated from previous samples in the Bay Estimated from previous samples in the Bay (Dauer 2000, 2002 sampling of Elizabeth River)(Dauer 2000, 2002 sampling of Elizabeth River)

8. Calculations - Benthos  Total Infaunal Biomass (g AFDW m -2 ) Bivalves – est. from length/weight regression Bivalves – est. from length/weight regression Remaining Infauna Remaining Infauna (Dauer 2000, 2002 sampling of Elizabeth River)(Dauer 2000, 2002 sampling of Elizabeth River)  Multiply by a range of published P:B (Diaz and Schaffner 1990; Baird and Ulanowicz 1989)(Diaz and Schaffner 1990; Baird and Ulanowicz 1989)  Production of benthos (g AFDW m -2 /yr)  Multiply by area of benthos lost per reef type (g AFDW/yr)

9. Calculations - Oysters  Biomass of oysters (g AFDW m -2 ) Oyster shell – Fishermen’s Island, lower Bay Oyster shell – Fishermen’s Island, lower Bay O’Beirn et al. 1999O’Beirn et al. 1999 Modules – Rappahannock River Modules – Rappahannock River Lipcius and Burke 2006Lipcius and Burke 2006 Rip rap – Lynnhaven system Rip rap – Lynnhaven system Burke (in progress)Burke (in progress) Reef balls – 90% module and 10% shell Reef balls – 90% module and 10% shell  Multiply by a published P:B Dame 1976; Bahr and Lanier 1981Dame 1976; Bahr and Lanier 1981  Production of oysters (g AFDW m -2 /yr)  Multiply by area available for settlement per reef type (g AFDW/yr)

10. Results - Benthos SiteBivalve Biomass (g AFDW m -2 ) Remaining Infauna Biomass (g AFDW m -2 ) P:BProduction (g AFDW m -2 /yr) Eastern Branch 19.660.9312.9 - 7.759.7 – 158.6 Linkhorn9.730.9312.9 - 7.730.9 – 36.9

11. Results – Oysters Reef Type Biomass (g AFDW m -2 ) P:BProduction (g AFDW m -2 /yr) Area (m 2 ) Total Production (g AFDW/yr) Oyster Shell 6002.414400.656945 * 3 = 2,835 Rip Rap45.42.41090.65671.5 * 3 = 214.5 Module13.72.432.94.3141.5 * 3 = 424.5 Reef Ball72.32.4173.52.4416.4 * 3 = 1,249

12. Benthos vs. Oysters 2,835 55% 63%

13. Conclusions  All reef types compensated for the lost benthic production at the site with lower productivity  Oyster shell and reef ball reefs compensated for the lost benthic production at the higher productivity site; however, the rip rap and module reefs may not compensate  Revisit the sites in the future Obtain actual oyster production values for the four reef types at each site Obtain actual oyster production values for the four reef types at each site Revaluate Revaluate  Important to characterize the benthic community prior to reef deployment Determine the best type of reef for a particular area Determine the best type of reef for a particular area

14. Acknowledgements  Dr. Rochelle Seitz, VIMS  Dr. Rom Lipcius, VIMS  Community Ecology Group, VIMS  Marine Conservation Biology Group, VIMS  Chesapeake Bay Foundation  US Army Corps of Engineers, Norfolk, VA Office  NOAA Chesapeake Bay Office