W2 AM Chesapeake Bay Restoration (Part 1)
Wednesday, 16 November 2005: 8:00 AM - 11:40 AM in Ballroom 2

(PAY-1122-409496) Oyster Restoration in Maryland.

Paynter, K¹, ¹ Department of Biology, University of Maryland

ABSTRACT- Oysters were an integral part of the Chesapeake Bay ecosystem that was almost entirely removed during the last century. Stocks are now thought to be less than 1% of historic levels and two diseases threaten rehabilitation efforts. Maryland waters, however, are generally low in salinity, which retards disease virulence and enhances oyster survival. Strategies to restore oyster populations include planting the native species, Crassostrea virginica, in high densities in low salinities to create large reef structures and testing a non-native species, Crassostrea ariakensis, for disease resistance and reef formation. Restoration efforts to date show that oysters planted in low salinities and protected from fishing will live relatively long lives and create substantial reef structure. These reefs may have far-reaching ecological value. Low salinity reefs protected from fishing experience 10 to 15% mortality annually and grow 2 to 3 cm/yr. When planted densely (250 to 500 seed oysters/m2) they create substantial and complex benthic structure. These structures, in turn, serve as valuable habitat to a variety of benthic species whose abundances are much higher on restored reefs compared to non-restored reefs. Because these reefs are composed of large animals in dense aggregations, the potential contributions of the oysters in a spatial context (/m2) may be quite high. Calculations based on literature values for filtration rates, nitrogen removal and larvae production suggest these reefs may filter vast quantities of water, remove ecologically-relevant amounts of nitrogen and produce billions of larvae on a per acre basis.

Key words: Chesapeake Bay, Oyster, Restoration, Nutrients