Note: At present, this type is no longer tracked as a natural community (see future marine aquatic classification).
Oyster beds occur in shallow estuarine waters of Great Bay. They are a subtidal natural community found almost exclusively below mean low tide, although their upper reaches may be briefly exposed during the lowest spring tides. They perform important ecological functions including supporting oyster populations, providing refuge for fish and invertebrates that retreat from exposed intertidal flats and estuarine marshes at low tide, and serving as spawning and nursery areas for numerous species of aquatic animals. Oysters (Crassostrea virginica) are an important food source for many other animals including starfish, crabs, fishes, and waterfowl.
An oyster bed community below the surface in Great Bay (photo by Ben Kimball)