Oyster reefs are similar to coral reefs because they also provide structures where plants and animals can live. Oysters form reefs when they reproduce and settle on the shells of other oysters and create a massive structure consisting of many individuals. Oysters provide a valuable ecosystem service by serving as “vacuum cleaners” and filtering particles from water, improving water quality. Oyster reefs or oyster bars also provide natural protection from storms and waves.
The intense harvesting of oysters, pollution and disease has impacted oyster reef habitats. Boat wakes can disturb and damage oysters. It is estimated that 85% of the Earth’s oyster reefs have been lost. Without this valuable habitat, marine life declines, shorelines erode and marshes are no longer protected. The National Park Service is working to assess and restore oyster populations in parks.