Salt Meadow NWR was established in 1972 and redesignated by Congress as the Connecticut Coastal National Wildlife Refuge in 1984. The refuge was renamed in 1987 to honor the late U.S. Congressman Stewart B. McKinney, who was instrumental in its establishment. The eight units of the Stewart B. McKinney National Wildlife Refuge span 60 miles of Connecticut coastline.

Located in the Atlantic Flyway, the refuge provides important resting, feeding, and nesting habitat for many species of wading birds, shorebirds, songbirds and terns, including the endangered roseate tern. Adjacent waters serve as wintering habitat for brant, scoters, American black duck and other waterfowl. Overall, the refuge encompasses over 800 acres of barrier beach, tidal wetland and fragile island habitats.

Salt Meadow Unit, in Westbrook, CT, and Falkner Island Unit, three miles off the coast of Guilford, CT, have both been designation as an "Important Bird Area" by the National Audubon Society. Falkner Island Unit is home to over 124 pairs of nesting Federally Endangered Roseate Terns and over 3000 nesting pairs of common terns. Salt Meadow Unit is used by over 280 species of migrating neotropical birds during the spring and fall migrations.