The Marais Audomarois is a wetland biosphere reserve in the north of France. The renowned Ramsar site covers some 22 300 hectares, including the city

Saint-Omer Saint-Omer (; vls, Sint-Omaars) is a commune and sub-prefecture of the Pas-de-Calais department in France. It is west-northwest of Lille on the railway to Calais, and is located in the Artois province. The town is named after Saint Audoma ...

Geography

The Audomarois landscape owes its richness to its particular geography. It is located on an intersection between three natural regions: the coastal plain, the Flanders intérieure and the Artois hills. These multifaceted landscapes are host to a wide variety of flora and fauna. The main natural habitats are reedbeds, tall herbs, peaty woods, meadows, ditches and rivers. The many species of flora include aquatic vegetation such as flowering rush (''

Butomus umbellatus ''Butomus umbellatus'' is a Eurasian plant species in the family Butomaceae. It is the only species in the family. Common names include flowering rush or grass rush. Introduced into North America as an ornamental plant it has now become a serious ...

''), greater spearwort ('' Ranunculus lingua'') and marsh fern (''

Thelypteris palustris ''Thelypteris palustris'', the marsh fern, or eastern marsh fern, is a species of fern native to eastern North America and across Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily ...

''), as well as underwater and floating vegetation. These habitat types enable many species of birds to breed, feed and rest. There are also a number of endangered species in the region, including cowbane (''

Cicuta virosa ''Cicuta virosa'', the cowbane or northern water hemlock, is a poisonous species of ''Cicuta'', native to northern and central Europe, northern Asia and northwestern North America. Description It is a perennial herbaceous plant which grows up ...

''), river water-dropwort (''

Oenanthe fluviatilis ''Oenanthe fluviatilis'', the river water-dropwort, is a flowering plant in the carrot family, Apiaceae, which is endemic to north-west Europe. It grows only in clear, unpolluted rivers and is declining throughout its range. Description River wa ...

'') and water soldier (''

Stratiotes aloides ''Stratiotes aloides'', commonly known as water soldiers or water pineapple, is a submerged aquatic plant native to Europe and northwestern Asia. In Britain it was once common in East Anglia and still is in many places, particularly wet ditches a ...

''). The natural heritage of the reserve is especially remarkable for the abundance and variety of its waterbird communities. Located on major migration routes, the Audomarois marsh provides food and necessary rest for birds such as sedge warblers (''

Acrocephalus schoenobaenus The sedge warbler (''Acrocephalus schoenobaenus'') is an Old World warbler in the genus '' Acrocephalus''. It is a medium-sized warbler with a brown, streaked back and wings and a distinct pale supercilium. Sedge warblers are migratory, crossin ...

''), the bluethroat ('' Luscinia svecica''), the warbler effarvate (''

Acrocephalus scirpaceus The common reed warbler (''Acrocephalus scirpaceus'') is an Old World warbler in the genus '' Acrocephalus''. It breeds across Europe into the temperate western Palaearctic where it is migratory, wintering in sub- Saharan Africa. It is also a re ...

'') and the rare aquatic warbler (''

Acrocephalus paludicola The aquatic warbler (''Acrocephalus paludicola'') is an Old World warbler in the genus '' Acrocephalus''. It breeds in temperate eastern Europe and western Asia, with an estimated population of 11,000-15,000 pairs. It is migratory, wintering in ...

''). In view of this natural wealth (flora, fauna and landscapes), the Audomarois marsh enjoys several forms of protected status, including inscription as a Natura 2000 Site, a National Nature Reserve, a Regional Natural Reserve and a Regional Natural Park. Since 2008, the wetland has also been recognized as a place of international importance under the

Ramsar Convention The Ramsar Convention on Wetlands of International Importance Especially as Waterfowl Habitat is an international treaty for the conservation and sustainable use of Ramsar site, Ramsar sites (wetlands). It is also known as the Convention on W ...

Socioeconomic characteristics

The reserve has a permanent population of 69 000 residents, as well as one of France’s two remaining wetland

floating gardens Chinampa ( nah, chināmitl ) is a technique used in Mesoamerican agriculture which relies on small, rectangular areas of fertile arable land to grow crops on the shallow lake beds in the Valley of Mexico. They are built up on wetlands of a lake ...

, the other being the in

Amiens Amiens (English: or ; ; pcd, Anmien, or ) is a city and commune in northern France, located north of Paris and south-west of Lille. It is the capital of the Somme department in the region of Hauts-de-France. In 2021, the population of ...

. Since the seventeenth century, market gardening activities have promoted the development and creation of these landscapes, which are still preserved today. The gardens are characterized by a system of (water management units or small canals) crucial for the prevention and management of floods. The reserve is also a highly valued site for leisure and tourism.

References

Sources

{{Coord, 50, 47, 07, N, 02, 13, 56, E, region:FR_scale:100000, display=title Biosphere reserves of France Ramsar sites in Metropolitan France Saint-Omer