St. Johns National Wildlife Refuge (SJNWR) was established in 1971 to protect the dusky seaside sparrow. In 1990, the species was officially declared extinct and the critical habitat was delisted. Today, SJNWR is managed to provide habitat for several species of birds listed as species of special management concern by the U.S. Fish and Wildlife Service and for wildlife and habitat diversity, primarily by prescribed fire. A marsh restoration project was conducted on the Highway 50 Unit in 1990 to return sheetflow from the St. Johns River. Dike roads traversing the Refuge in an east-west fashion were removed and clumps of spartina were planted.