Poor water quality, disease, and harvesting nearly put an end to native oyster (Crassostrea virginica) in Chesapeake Bay. Restoration of the bay to pre-Columbian levels is challenging. The film commissioned by the Chesapeake Bay Foundation explores the ecology of this keystone species providing services to maintain a healthy biological community.
A single oyster can filter up to 50 gallons of water in the Chesapeake Bay in a single day. Oysters filter nutrient and suspended sediment from the water column. Moreover, oyster reefs create a stable hard-surfaced habitat for a variety of aquatic life. These reefs are essential for many fish in shallow marine habitats.
Hard surfaces are a valuable commodity in aquatic systems. For instance, in rivers of southeastern US bluehead chub fish construct nests out of rocks they carry in southeastern rivers. These constructed hard surfaces become protected islands against silt. Bluehead chub nests attract large spawning aggregations from 7 species of fish.
The ecological significance of oysters is evident from the name of the bay. Chesapeake meant ‘great shellfish bay’ in the local native american language. There are efforts to restore oyster reefs. Currently native oyster populations in Chesapeake Bay are at less than 1% of historic levels.
Beginning in 2002, NOAA expanded its restoration activities in Virginia through a cooperative agreement with the Virginia Oyster Reef Heritage Foundation, as well as continuing with work in Maryland. Efforts in Maryland was focused for hatchery production of spat-on-shell for sites restored with other non-NOAA works. Efforts in Virginia was involved placement of dredged-shell (2002) or shuck-house shell (2003) on restoration sites in a number of tributaries, most notably the lower Rappahannock River. Shells deposited in pre-chosen sites in Chesapeake Bay serve as colonization surfaces for oyster larvae to settle on and form new reefs.
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