Coastal and Floodplain Grazing Marsh

What are the challenges?

• Kent’s coastal and floodplain grazing marshes face mounting threats from climate change, habitat loss, and pollution:

• Artificial sea walls that protect areas from flooding, along with Sea Level Rise are causing the coastal habitat to be squeezed, leaving limited space for mudflats and saltmarsh, both vital for coastal wildlife and supporting the large numbers of overwintering and migratory birds that the Kent coast is highly designated for.

• Sea level rise and coastal management is also contributing to the loss of islands that are important for nesting and roosing birds.

• Coastal erosion is a natural process that provides sediment to the coast from cliffs and raising ground, where there are opportunities to allow this to occur should be supported, it is also a feature of some of the designated features of cliffs.

• Historic drainage for agriculture has degraded biodiversity, reduced water quality, and led to sharp declines in species like Lapwings (down 63% since the 1960s) and Redshanks.

• Rising sea levels and hotter, drier summers threaten freshwater wetland species, including breeding waders. Freshwater habitats are vital and we should look at areas where these can be maintained, they are likely to be vulnerable behind seawalls and there are opportunites at these locations for transitional habitats to be created and freshwater sites located further up the catchment or where the hydrology best supports them, or areas not subject to coastal inundation.

• Coastal grazing marshes below 5m AOD are highly vulnerable, requiring realignment and habitat compensation.

• Agricultural runoff, wastewater, and nitrogen deposition contribute to eutrophication, harming marsh ecosystems and intertidal vegetation.

Why it matters:

• Kent’s coastal landscapes, including the Medway and Swale estuary, support internationally important populations of migratory, breeding, and wintering waders and wildfowl.

• Working with natural processes and creating space for our coastline to adapt is vital to support internationally important populations of migratory, breeding, and wintering waders and wildfowl.

• Birds that are feeding on the intertidal mud flats, at high tide then roosting or feeding on the associated grazing marsh. Showing these transitional habitats are essential in supporting the designated sites.

• Grazing marshes provide essential feeding and roosting grounds for birds.

• Increases in the space for nature supports a balanced and healthy species interaction (predator and prey), i.e. supporting designated species such as the marsh harrier, lapwing and redshank.

• Well-managed grazing marshes absorb floodwaters, reducing coastal flood risks.

• Wetland soils/intertidal mud act as carbon sinks, helping to mitigate climate change.

When well managed and healthy, this habitat achieves the following:

• Reversing Biodiversity Loss

• Habitat for rare or endangered species

• Water Quality

• Flood Mitigation & Climate Change Resilience

• Carbon Sequestration

• Soil Health

• Connecting People to Nature

• Supports pollinators & food production

Nature Based Solutions:

• Working with natural processes to support and create intertidal habitat.

• Restore grazing marsh through sustainable grazing, hydrological management, and saltmarsh rehabilitation.

• Working at a catchment scale to ensure that freshwater habitats can be maintained in sustainable locations away from saline intrusion or overtopping if nature features are sensitive to this impact.

• Manage predators to support breeding wader populations.

Statistics & Facts:

• Medway Estuary and Marshes SSSI, SPA and Ramser covers 4748.8ha and The Swale SSSI SPA, covers 6509.3ha, both of which are functionally linked and comprises of mud flats, saltmarsh and grazing marshes.

• Due to coastal Squeeze and Hold the Line impacts, across the Medway and Swale calculations shows over 300ha of coastal habitat will be lost by 2105, unless space can be created to address these losses and freshwater habitat relocated elsewhere ideally on the adjacent higher ground.

• Medway Estuary and Marshes SSSI is under pressure from water company discharges causing water pollution, invasive non-native species, unsuitable land management regimes and coastal squeeze.

Key Species:

• Lapwing (Vanellus vanellus) – A wader species suffering severe population declines.

• Redshank (Tringa totanus) – A key indicator of healthy coastal wetlands.

• Marsh Harrier (Circus aeruginosus) – A top predator dependent on wetland habitats.

• European Hare (Lepus europaeus) – Found in grassland mosaics within grazing marshes.

• Water Vole (Arvicola amphibius) – A wetland species vulnerable to habitat degradation.