Close-up of Virginia Oysters being farmed close to the US175 Chincoteague Rd. along the John B. Whealton Memorial Causeway, Virginia, USA
Oysters have been cultured since at least the days of the Roman Empire. The Pacific oyster (Magallana gigas) is presently the most widely grown bivalve around the world. Two methods are commonly used, release and bagging. In both cases, oysters are cultivated onshore to the size of spat, when they can attach themselves to a substrate. They may be allowed to mature further to form "seed oysters". In either case, they are then placed in the water to mature. The release technique involves distributing the spat throughout existing oyster beds, allowing them to mature naturally to be collected like wild oysters. Bagging has the cultivator putting spat in racks or bags and keeping them above the bottom. Harvesting involves simply lifting the bags or rack to the surface and removing the mature oysters. The latter method prevents losses to some predators, but is more expensive. The Pacific oyster has been grown in the outflow of mariculture ponds. When fish or prawns are grown in ponds, it takes typically 10 kg (22 lb) of feed to produce 1 kg (2+1⁄4 lb) of product (dry-dry basis). The other 9 kg (20 lb) goes into the pond and after mineralization, provides food for phytoplankton, which in turn feeds the oyster. To prevent spawning, sterile oysters are now cultured by crossbreeding tetraploid and diploid oysters. The resulting triploid oyster cannot propagate, which prevents introduced oysters from spreading into unwanted habitats. The eastern oyster (Crassostrea virginica)—also called the Atlantic oyster, American oyster, or East Coast oyster—is a species of true oyster native to eastern North and South America. Other names in local or culinary use include the Wellfleet oyster, Virginia oyster, Malpeque oyster, Blue Point oyster, Chesapeake Bay oyster, and Apalachicola oyster. C. virginica ranges from northern New Brunswick through parts of the West Indies and south to Brazil. It is farmed in all of the Maritime provinces of Canada and all Eastern Seaboard and Gulf s
Size: 5616px × 3744px
Location: US175 Chincoteague Rd. along the John B. Whealton Memorial Causeway.
Photo credit: © John Gaffen / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., american, aquaculture, atlantic, barnicles, bay, bivalve, calcite, calcium, carbonaceous, chesapeake, chincoteague, close-, coast, commercial, crassostrea, crustaceans, cultivation, east, eastern, farming, feeder., filter, food, foundation, hard, important, industry, isopods, molluscs, oyster, oysters, reef, restoration, salt-water, seafood, shell, shells, shells., species, species., usa, virginia, virginica, water
