Coastal and Flood Plain Grazing Marsh
Grazing marshes are periodically inundated grasslands found in low-lying coastal areas or within the flood plains of rivers. They usually have high water levels which are maintained by ditches containing standing brackish or fresh water. Almost all sites are grazed and some are cut for hay or silage. Sites may contain seasonal water-filled hollows and permanent ponds with emergent swamp communities, but not extensive areas of tall fen species such as reed.
The ditches which typically criss-cross grazing marshes may be particularly rich in plants and invertebrates. The habitat is also particularly important for breeding, passage and wintering birds including species such as lapwing, snipe and teal.
There is thought to be 200 000 ha of grazing marsh in England, of which only 5000 ha is semi-natural and supports a high diversity of native plant species. There have been significant losses of the habitat in the last 60 years and most sites are very sensitive to changes in grazing, cutting, and flooding regime.
Within the North East, grazing marsh is concentrated along the lower-lying areas of the north Northumberland coast and the Tees Estuary. There are areas of grazing marsh adjacent to five coastal SSSIs in Northumberland.They do not form part of the notified interest features of the sites but contribute tothe valuable mix of coastal habitats present. Cowpen Marsh SSSI on the TeesEstuary includes significant areas of grazing marsh and forms part of the Teesmouthand Cleveland Coast SPA, designated in recognition of its importance for passage and wintering birds. Two other SSSIs on the Tees Estuary contain examples of the habitat.
- Neglect of sites, including a decline in traditional management techniques such as maintenance of water levels.
- Agricultural intensification, including the loss of sites due to drainage and fertilizer applications.
- Nutrient enrichment and other forms of water pollution.
- In the past, creation of flood defences has been part of a process of agricultural improvement which has resulted in the loss of significant areas of grazing marsh.
- Overgrazing leading to the loss of tall vegetation required by some breeding bird species or cessation of grazing leading to a loss of structural diversity.
- Disturbance of bird species caused by human activities.
Opportunities for protection and enhancement
- The creation of flood storage/washland areas for flood defence purposes offers the opportunity to create new areas of grazing marsh.
- On the Millfield Plain in Northumberland, the River Till Restoration Project is creating and restoring fllodplain and wetland habitat.
- The RSPB have created 40ha of wet grassland on Teesside as part of their Saltholme Nature Reserve.