The Site, set in an agricultural plain dominated by the hills of the Côte de Meuse, consists of a high density of ponds created by the draining of a marsh by monks in the Middle Ages to rear fish. The lakes and ponds are interspersed by woodland, farmland, wet meadows and reedbeds. The Site’s lakes, forests and meadows are home to thousands of migrating birds. A total of 183 species have been identified, some of which breed there: little bittern (Ixobrychus minutus), little crake (Porzana parva), western marsh harrier (Circus aeruginosus) and Eurasian bittern (Botaurus stellaris). Amphibians can be found in high densities in the numerous reedbeds inaccessible to fish and, above all, the many meadow pools close to forest habitats necessary for their wintering. Most of the ponds are home to great crested newts (Triturus cristatus) and green tree frogs (Hyla arborea), as well as aquatic insects such as the lilypad whiteface drafgonfly (Leucorrhinia caudalis). The peripheral hedgerow-rich meadows provide travel and hunting grounds for many mammals, including wildcats (Felis silvestris) and a number of bat species including the Geoffroy’s bat (Myotis emarginatus), the western barbastelle (Barbastella barbastellus), the greater and lesser horseshoe bat (Rhinolophus ferrumequinum and R. hipposideos), and the greater mouse-eared bat (Myotis myotis). A management plan is in place to counter the intensification of agriculture around the Site, the drying of wet meadows and the use of fertilizer and pesticides.