Salt marshes fringe estuarine waters, forming the intertidal zone (between high and low tide) along beaches and tidal rivers. South Carolina has more salt marsh than any other state on the east coast (about 400,000 acres) and Charleston County has the most salt marsh of any county in South Carolina. Salt marshes are complex and ecologically productive, with fluctuating levels of salinity and temperature as the tides move in and out.
Most low salt marsh areas (nearest to the water) are dominated by smooth cordgrass (Spartina). A mix of plants including Spartina and black needlerush (Juncus) are found in the higher areas of marsh. As the marsh grass decays in the fall, it decomposes into a rich soup of nutrients providing food for both fish and invertebrates like shrimp, blue crabs, stone crabs and clams. Fiddler crabs, marsh snails and marsh mussels are also typical marsh inhabitants.
Salt marshes also serve as high quality bird habitat, attracting, for example, blue herons and American and snowy egrets, seaside sparrows, clapper rails and marsh rails as year-round marsh residents. Waterfowl (ducks and geese) and wading birds find shelter in the marshes over the winter. Other inhabitants of our coastal marshes include muskrats, rabbits, diamond back terrapins and even alligators in less salty areas. Learn more about the Charleston Harbor watershed’s estuarine habitat.