Discovering the moyenne vallée de l’OISE
Thursday 14 March 2013, by
All the versions of this article: [English] [français]
type of environment
Land uses in the Moyenne vallée de l’Oise
Grasslands are the dominant land use within this Natura 2000 site, occupying an area of 3 017 ha, or 51 % of the total surface. Woodland occupies about 30 % of the surface of the Natura 2000 site, and crops nearly 10 %. Much of the woodland and crops occurs on the lower slopes of the valley downstream from Noyon. Since this area lies outside the SPA, this partly explains the lower proportion of woodland and cultures within the SPA’s perimeter, 19 % and 2 %.
Industrial activities are concentrated around a few industrial hubs (La Fere, Tergnier, Chauny). Further downstream, between Abbécourt and Noyon, the valley has a more rural character. From Noyon on, the valley again takes on a more industrial aspect. Granulate extraction has taken place in several areas of the valley. These areas, approximately 350 ha, were excluded from the perimeter of the SAC.
For greater convenience of the area calculations, they were also excluded from the surface of the SAC and the Natura 2000 site. Despite these exclusions, there are still 62 ha of gravel pits in the SAC (Varesnes and banks of the Oise to Tergnier) and 23 ha in the SPA (Varesnes and banks of the Oise to Tergnier), recorded in the water expanse and artificial areas.
The majority of the site is private property. Municipalities also own land in this sector. The river Oise is public domain. Leisure activities (hunting, fishing, birdwatching and other outdoor activities) and tourism (mainly on the river) are important socio-economic activities.
Biodiversity in the Moyenne vallée de l’Oise
Located in the heart of Picardy, the Natura 2000 site “Moyenne vallée de l’Oise” with a total area of 5 929 ha, is an inter-departmental site located along the central stretch of the river Oise, between La Fere (Aisne department) upstream and Compiegne (Oise department) downstream.
With a length of 300 km, the Oise has its source in the Belgian Ardennes and flows into the Seine at Conflans-Sainte-Honorine (Val d’Oise). Its water catchment area of 1.6 million acres, collecting and draining precipitation, covers two thirds of Picardy.
The alluvial plains of the Moyenne vallée de l’Oise are important for the qualitative and quantitative management of water resources. They play a fundamental role in flood control and water treatment.
The Moyenne vallée de l’Oise is a mosaic of habitats consisting of extensive areas of hayfields and pastures with numerous depressions, ponds and patches of alluvial woodland :
- open environments characterized by alluvial meadows ;
- freshwater environments characterized by the Oise River, ponds, oxbows and channels ...
- wooded environments characterized by riparian woodlands, alluvial woodlands and hedgerows.
The site hosts:
- 22 species protected by French law, 41 species rare in Picardy, and 2 species on the Red Book of endangered species in France (Annex II)
- 12 species of breeding birds and 11 key migratory and wintering species listed in Annex I of the "Birds Directive" in the SPA
- 8 habitats listed in the Directive "Habitats" in the SAC
The site is a reservoir of biodiversity for wildlife: birds, fish, invertebrates, and for flora (notable vegetation groups and several protected species).
The avifaunal interest of the SPA is primarily related to wet meadows and associated environments. Some woodlands and small bodies of water (oxbows, ponds ...) are also welcoming environments for high-value species. The avifaunal interest of the SPA remains high throughout the year; nevertheless, the breeding period is of very special interest because of the occurrence of several species in decline in the Western European plains, such as the Corncrake or the Whinchat.
The Corncrake in the Moyenne vallée de l’Oise
The conservation status of the Corncrake is extremely unfavorable in the Oise valley, as it is in Picardy generally, in France and in the entire European Union. Consequently, this site was designated as a Special Protection Area for the Corncrake in 1996 in Annex I of the Birds Directive.
Today, with 51 calling males (2009 survey), Picardy is the second most important site for Corncrakes in France. The Moyenne vallée de l’Oise is the foremost site in Picardy with 33 males, that is to say 6 % of the French population. But the numbers remain low in spite of the great potential that the Oise valley, with 3 000 ha of grassland, would have for hosting the species.
For 20 years, Corncrake populations in the Oise valley have been steady, with year on year variations that appear to be related to spring rainfall, an important factor in encouraging Corncrakes to breed in the valley on their return from migration.
Significant efforts have been made to induce the farming profession to manage grasslands in a more extensive way and to delay mowing. It has been recorded that during the "good years" for these birds, the calling males are mostly limited to areas where mowing takes place later. And even during the worst drought years, these rare birds are restricted to and sighted in wetlands with late mowing. These wettest areas are those most threatened by abandonment by agriculture and conversion into poplar groves. Sustainability of extensive farming activities is therefore essential to ensure the survival of the species and guarantee reliable breeding.
Protection of the Moyenne vallée de l’Oise
- Area: 5 929 Ha
- Special Protection Area (Europe): FR2210104
- Special Area of Conservation (Europe): FR2200383
- Important Bird Area (IBA) in (PE07 on 12,050 ha)
- ZNIEFF (high-value ecological area) : Type II (large ecological preserved sets) and ZNIEFF type I (presence of high value flora and fauna species)