Marais du Fier d'Ars. 02/02/03; Poitou-Charentes; 4,452 ha; 46°13'N 001°28'W. Nature Reserve (119 ha), Special Protection Area and proposed Site of Community Importance EC Directives. A complex of tidal sands and mudflats and diked marshes on the island of Ré off the Atlantic coast, including active and abandoned salt pans, freshwater marshes, reedbeds, oyster basins, extensive salt pastures, active dunes, dune forests, sandy and rocky coasts, and important seagrass beds (Zostera noltii). The site harbours a number of plant and animal species of conservation concern, including two regional endemics, the dune plant Omphalodes littoralis and the subspecies of the bluethroat Luscinia svecica namnetum. More than 31,000 waterbirds use the site in winter. Four populations of them occur regularly above the 1% threshold: Branta bernicla bernicla, Recurvirostra avoseta, Calidris alpina, Limosa limosa islandica. Human uses include oyster farming and numerous leasure and tourist activities (cycling, walking, fishing, canoeing, angling, sailing, swimming). Two visitor centres provide education facilities. Ramsar site no. 1269. Most recent RIS information: 2002.