The marshes and peatlands of the Bugey mountains consist of a total of 41 wetlands, with the crests of the southern Jura range running between them from north to south. The Site includes a wide range of natural environments including woodlands, peat bogs, marshes, dry grasslands, glacial lakes and ponds. This mosaic of environments supports a variety of habitats in which a number of globally, nationally and regionally threatened plants and animals are found. Thirty-five regionally or nationally threatened plant species are to be found in the Site, notably including species such as the fen orchid (Liparis loeselii) and the Siberian iris (Iris sibirica). Among the birds that use the Site, 19 species are listed in the IUCN Red List and are nationally threatened. Common snipe (Gallinago gallinago), black storks (Ciconia nigra) and white storks (Ciconia ciconia) use the Site for migratory stopovers, while several species of passerine birds use these wetlands for nesting. A large population of the endangered white-clawed crayfish (Austropotamobius pallipes) is maintained in a stream located in the heart of one of the wetlands. The marshes and peat bogs of the Bugey mountains provide particularly important ecosystem services in terms of water resources, carbon storage as well as opportunities for recreational activities. Drainage operations, increasing tourism and climate change have impacted the wetlands. However, numerous environmental restoration operations have already been carried out, helping to restore certain ecological functions, and future actions are planned.