Within an estuary, there are four habitats: open water, eelgrass beds, tidal flats and salt marshes. A fifth habitat, the uplands, is the land adjacent to the estuary.

Open-Water Habitat
Never exposed by the tides, the open water is a deep water habitat. Fish, seals, sea lions, and occasionally whales move into this habitat from the ocean, seeking food and shelter from predators.

Eelgrass Habitat
Adjacent to the open-water habitat are the eelgrass beds, a wetland habitat that is exposed only by the lowest tides. Eelgrass forms dense, underwater meadows—nurseries that provide shelter and food to many juvenile fish and shellfish.

Tidal Flat Habitat
At low tide you will see the tidal flats. Although tidal flats appear barren from a distance, a close view reveals the myriad organisms that make a home in this wetland habitat.

Upland Habitat
The habitat next to the estuary, the uplands, begins where the highest high tide of the year stops. Most of the HMSC trail passes through the upland habitat. While spring and summer are the best times to see flowers along the estuary, many of the perennial plants are easily identified throughout the year.

Salt Marsh Habitat
The salt marsh is a wetland habitat that lies in protected areas along the fringes of the estuary, above the tidal flats and below the uplands. Because daily tides expose the salt marsh to air, aquatic animals are not common. Those that do occur usually migrate in and out with the tides.

Sobering Facts

Estuaries are fascinating and beautiful ecosystems, distinct from all other places. Estuarine environments are among the most productive on earth, creating more organic matter each year than an equivalent amount of agricultural land. The productivity and variety of estuarine habitats foster a wonderful abundance and diversity of wildlife.

Much of our estuary habitat, however, is being destroyed and damaged. Waters entering the estuaries bring silt and sediments eroded from the land, as well as sewage, animal wastes, pesticides, chemical fertilizers, and industrial discard. As estuary habitat is lost, it cripples an estuary’s ability to support life.

Fortunately, people are acting to save these vital, productive and important environments. The National Estuarine Research Reserve System, under the auspices of the National Oceanic and Atmospheric Administration, exists to safeguard our estuarine resources and provide educational and research facilities to protect these critical habitats. The Clean Water Act of 1987 established a National Estuary Program, administered by the Environmental Protection Agency, that has identified 11 of the nation’s major estuaries and is working to improve their quality.

Restore America’s Estuaries consists of community-based organizations whose goal is to reclaim one million acres of estuary habitat. These and other organizations have established frameworks and put legislative tools at our disposal to begin to reverse some of the processes that have deteriorated the quality of the nation’s most valuable waterways