Coastal wetlands include a number of natural communities that share the unique combination of aquatic, semi-aquatic, and terrestrial habitats that results from periodic flooding by tidal waters, rainfall, or runoff.
Wetlands provide a habitat for a vast array of organisms, including many endangered species.
During peak annual migration periods, hundreds of thousands of birds migrating along the Pacific Flyway descend upon these coastal wetlands in search of refuge and food. Coastal wetlands provide a vital link between land and open sea, exporting nutrients and organic material to ocean waters, and harboring juveniles of numerous aquatic species including many fish. Water flow in these highly productive communities circulates food, nutrients, and waste products throughout the system. Wetlands buffer the effects of storms, reducing shoreline erosion, and improve water quality by filtering and assimilating many pollutants from sewage outfalls and agricultural runoff. In addition, wetlands provide a unique opportunity for nature study.