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 south through parts of the West Indies to Venezuela. It is farmed in all of the Maritime provinces of Canada and all Eastern Seaboard and Gulf states of the United States, as well as Puget Sound, Washington, where it is known as the Totten Inlet Virginica. It was introduced to the Hawaiian Islands in the 19th century and is common in Pearl Harbor.
The eastern oyster is an important commercial species. Its distribution has been affected by habitat change; less than 1% of the population present when the first European colonists arrived is thought to remain in the Chesapeake Bay and its tributaries. As of 2014, the global conservation status of Crassostrea virginica, as assessed by NatureServe, is "vulnerable," as the oyster's populations are threatened by overharvest and water pollution. Other threats to the eastern oyster include global warming, diseases and parasites, and competition with invasive species.
Oyster#Physical characteristics
Like all oysters, C. virginica is a bivalve mollusk with a hard calcium carbonaceous shell that protects it from predation.
This particular type of oyster is important to its ecosystem. Like all oysters, C. virginica is a filter feeder. It sucks in water and filters out the plankton and detritus to swallow, then spits the water back out, thus cleaning the water around it. One oyster can filter up to 50 gallons of water in 24 hours. Eastern oysters also provide a key structural element within their ecosystem, making them a foundation species in many environments, and they serve as ecosystem engineers in western Atlantic estuaries.