The Banc d'Arguin National Park lies on the west coast of Mauritania between Nouakchott and Nouadhibou. Fringing the Atlantic coast, the park comprises sand dunes, coastal swamps, small islands, and shallow coastal waters.
It is a major breeding site for migratory birds. A wide range of species include flamingos, broad-billed sandpipers, pelicans, and terns. The park's vast expanses of mudflats provide a home for over two million migrant shorebirds from northern Europe, Siberia, and Greenland. The region's mild climate and absence of human disturbance makes the park one of the most important sites in the world for these species. The nesting bird population is also noted for its great numbers and diversity—between 25,000 and 40,000 pairs belonging to 15 species—making the largest colonies of water birds in West Africa.
The 12,000 km² (4,633mi²) National Park was created by decree on June 24, 1976 and established in 1978. The wetlands area was designated a Wetland of International Importance under the Ramsar Convention in 1982. Two outlying satellite reserves, Baie du Lévrier Integral Reserve on Cap Blanc and Cuevecillas Integral Reserve on the Côte des Phoques, were added in 1986. It was inscribed as a UNESCO World Heritage Site in 1989.