FAQ – The Audomarois marsh and other marshes in the North and in France

The Audomarois marsh and the Poitevin marsh are two important wetlands in France, but they have several notable differences:

Size: The Audomarois marsh covers an area of ​​37 km² (3,726 hectares), while the Poitevin marsh extends over a much larger area of ​​112,000 hectares.

Location: The Audomarois marshland is located in northern France, extending across 15 communes in the Pas-de-Calais and Nord departments. The Poitevin marshland, on the other hand, is located in western France, between Niort and the Bay of Aiguillon.

Agricultural activity: The Audomarois marsh remains today the only marsh of this size still cultivated for market gardening in France, with nearly fifty different vegetables grown. In contrast, the Marais Poitevin has been largely drained and used for cereal cultivation.

Recognition: The Audomarois marsh was designated a Ramsar site and declared the "twelfth French biosphere reserve" by UNESCO in 2013. The Marais Poitevin is labeled a Regional Natural Park and a Grand Site de France.

Landscape: The Audomarois marsh is characterized by its canals called watringues or watergang. The Poitevin marsh, on the other hand, is known for its "Green Venice", a part of the wet marsh crisscrossed by tree-lined canals.

Tourism: Although both marshes offer tourist activities, the Marais Poitevin has a more developed tourist vocation, particularly with its traditional boat trips in the Green Venice.

The Audomarois marsh and the Amiens hortillonnages are two remarkable wetlands in France, but they have several significant differences:

Size: The Audomarois marsh is much larger, covering an area of ​​37,26 hectares (37.26 km²), while the Amiens market gardens are about 500 hectares.

Hydrographic network: The Audomarois marshland has a more extensive hydrographic network, with 170 km of rivers (wateringues) and 560 km of ditches (watergangs). The Amiens market gardens have a canal network estimated at 65 km.

Biodiversity: The Audomarois marshland is home to exceptional biodiversity, with 2,600 recorded species (fauna, flora, and fungi) and 50% of the region's aquatic flora. The Amiens market gardens, while rich in biodiversity, do not exhibit such diversity. By comparison, the Saint-Omer marshland has as many bird species as the Marquenterre.

International recognition: The Audomarois marsh benefits from several international labels, including the Ramsar classification (wetland of international importance) and the status of UNESCO Biosphere Reserve.

Agricultural activity: The Audomarois marshland is considered the last cultivated and inhabited marshland in France, with a market gardening tradition dating back to the 7th century. The Amiens market gardens (hortillonnages) are also known for their market gardening, but on a smaller scale (with the hortillons, the market gardeners of the hortillonnages). It should be noted that while a few hortillons still remain for the ultra-local consumption of vegetables, the Audomarois marshland still has 35 farming families cultivating 450 hectares of market garden land.

Tourism: The Amiens market gardens (hortillonnages) attract far more visitors each year than the Saint-Omer marshes. This is because Saint-Omer only developed its tourism activities relatively late. While boat rentals already existed in the Audomarois marshes during the 20th century (for example, the Moulin Rouge open-air café and the Pont Mathilde landing stage), the service became known beyond the region thanks to companies created during the 1990s. The classification of the Romelaere nature reserve in the 1980s and its UNESCO recognition in 2013 have significantly contributed to the marsh's current renown. But we have some catching up to do!

The Audomarois marsh and the Cotentin marsh are two important wetlands in France, but they have several notable differences:

Size: The Audomarois marsh covers an area of ​​37,26 hectares (37.26 km²)5, while the Cotentin marsh is much larger, extending over approximately 1500 km2.

Location: The Audomarois marsh is located in the North of France, extending over 15 communes in Pas-de-Calais and Nord. The Cotentin marsh is located in Normandy, straddling the departments of Manche and Calvados.

Hydrographic network: The Audomarois marsh has a dense hydrographic network, with 170 km of rivers (wateringues) and 560 km of ditches (watergangs). The Cotentin marsh does not provide precise figures for its hydrographic network (but given the area, this figure must be considerable).

Recognition: The Audomarois marshland is designated a Ramsar site and declared a "Biosphere Reserve" by UNESCO. The Cotentin marshland is part of a Regional Natural Park.

Agricultural activity: The Audomarois marsh is considered the last cultivated and inhabited marsh in France, with a market gardening tradition dating back to the Middle Ages. The Cotentin marsh is mainly characterized by grazed or mowed meadows.

Biodiversity: The Audomarois marshland is home to 2,600 recorded species (fauna, flora, and fungi) and 50% of the region's aquatic flora. The Cotentin marshland does not provide precise figures on its biodiversity.

The Audomarois marsh and the Brière marsh are two important wetlands in France, but they have several notable differences:

Size: The Audomarois marsh covers an area of ​​3,726 hectares, while the Grande Brière marsh extends over 7,000 hectares.

Hydrographic network: The Audomarois marsh has a denser network with 170 km of rivers (wateringues) and 560 km of ditches (watergangs). The Grande Brière marsh has 140 km of canals.

Ownership status: The Audomarois marshland is a territory recognized by various designations (Ramsar Site, UNESCO Biosphere Reserve). Its approximately 13,000 plots are privately owned (divided among 4000 owners). This configuration is also found in the Brière marshland. It should be noted, however, that in the latter case, the land is largely held in common by the inhabitants of the surrounding municipalities.

Management: The Grande Brière marsh is managed by the Grande Brière Mottière Joint Commission, while the Audomarois marsh is managed by the Caps et Marais d'Opale Regional Natural Park, Eden 62, the Wateringues, the Hauts de Flandres Community of Communes and the Pays de Saint-Omer Agglomeration Community.

Traditional activities: The Audomarois marshland is known for its market gardening, a tradition dating back to the 7th century. The Brière marshland has historically been associated with peat harvesting (sods) and livestock farming.

Biodiversity: The Audomarois marsh is home to 2,600 listed species and 50% of the regional aquatic flora.

There are several other wetlands and marshes in Hauts-de-France:

The Scarpe-Escaut area: This is one of the two wetlands of national or international importance selected by France in the Nord-Pas-de-Calais region, along with the Audomarois marsh.

Marine and coastal environments: These include dune slacks and backshore marshes.

Ponds and wetlands resulting from mining subsidence: They form the third main unit of wetlands in the region.

The Rotten Marsh : Located on the border of the municipalities of Ham and Norrent-Fontes, it is a wetland of 137 hectares composed of market garden plots, watercress beds, woods, former peat bogs, a reedbed and a stream fed by artesian wells.

The Guines marsh , extending over 160 hectares between Ardres and Guines.

It is important to note that despite the existence of these wetlands, they are generally in decline in the region, despite their importance for water management and biodiversity.