Tidal Marshes

Tidal marshes of the shallows are border habitats that connect shorelines to forests and wetlands. Like wetlands and underwater bay grass beds, tidal marshes provide food and shelter for the numerous aquatic species that dwell in shallow waters.

There are three types of tidal marshes found in the Bay:

• Freshwater marshes of the upper Bay
• Brackish marshes of the middle Bay
• Salt marshes of the lower Bay

Freshwater Marshes

Tidal freshwater marshes support a greater diversity of plant species than do salt marshes. Freshwater marshes are filled with a variety of emergent plants that reach the water's surface, including arrow arum and narrow-leaved cattails.

Freshwater marshes along the Bay are home to frogs, muskrats, marsh-nesting birds and a host of other animals. They also help control flood waters and improve water quality by trapping and filtering nutrients and sediments.

Brackish Marshes

Marshes that grow along the brackish waters of the middle Bay mark the transition from freshwater marshes to salt marshes. Cattails, phragmites and three-squares grow in brackish marshes, which provide food and habitat for mammals, reptiles and many different types of birds.

Salt Marshes

Salt marshes are wetlands dominated by cordgrass, also called Spartina. They are one of the most productive plant communities on earth. Salt marshes are located above and below the high tide line.

• Low marshes are regularly flooded by the tides. The tall form of smooth cordgrass grows here. Low marshes serve as critical habitat for juvenile fish, as well as shrimps, fiddler crabs, marsh crabs, marsh periwinkles and ribbed mussels.
• High marshes are irregularly flooded by strong winds or exceptionally high tides. Three-squares, saltmeadow cordgrass and the short form of smooth cordgrass grow here.