Eastern oyster

Eastern Oyster (Crassostrea virginica) is a species of true oyster native to the eastern seaboard and Gulf of Mexico coast of North America. It is also known as the American oyster, Atlantic oyster, or Virginia oyster.

Description

The Eastern oyster is a bivalve mollusk with a rough, irregularly shaped shell. The color of the shell is usually grayish-white to grayish-brown. The inside of the shell is white with a purple muscle scar. The Eastern oyster can reach a maximum size of about 8 inches (20 cm) in shell height.

Habitat and Distribution

Eastern oysters are found in coastal waters along the Atlantic coast of North America, from the Gulf of St. Lawrence in Canada to the Gulf of Mexico. They inhabit intertidal and subtidal zones of estuaries and bays, where they attach themselves to hard substrates, often forming extensive oyster reefs.

Life Cycle and Reproduction

Eastern oysters are protandric sequential hermaphrodites, meaning they begin life as males and later change into females. Spawning occurs in the summer when water temperatures rise. After spawning, the fertilized eggs develop into planktonic larvae, which after several weeks metamorphose into juvenile oysters, or "spat", and settle onto a suitable substrate.

Economic Importance

Eastern oysters are commercially important and have been harvested for centuries for their meat and shells. They are also important ecologically, as they filter water and provide habitat for a variety of other species.

Conservation

Overfishing, habitat loss, pollution, and diseases such as Dermo and MSX have caused significant declines in Eastern oyster populations. Efforts are being made to restore oyster populations through aquaculture and reef restoration projects.

See Also

• Oyster farming
• Oyster diseases
• Oyster reef