Ecosystems · Marine, Europe

Wadden Sea And North Sea Coast

Vast tidal flats where millions of birds refuel.

The Wadden Sea runs along the North Sea coasts of the Netherlands, Germany and Denmark. It is recognised as a World Heritage site and is the largest unbroken system of tidal sand and mud flats in the world.

Every day the tide covers and uncovers a landscape of channels, mudflats, salt marsh and islands.

The Landscape

Twice-daily tides sweep across shallow flats, creating a mosaic of sandbanks and gullies. The mud is rich in worms and shellfish, and salt marshes on the edges are important for plants and nesting birds.

Who Lives Here

Harbour Seals and Grey Seals haul out on sandbanks, and millions of migratory birds, including Red Knot, Eurasian Oystercatcher, Common Eider and Barnacle Goose, use the flats as a feeding stop on the East Atlantic Flyway.

Through The Year

Spring and autumn bring the biggest bird migrations, summer brings breeding terns and seal pups, and winter brings geese and seaduck. Tide tables decide what you can see and when.

Pressures And Care

Dredging and shipping, fisheries, offshore energy, nutrient pollution and sea-level rise affect the Wadden Sea, as does disturbance from visitors. International cooperation protects the whole system.

Visiting Well

Check tide times, never walk the flats without a guide because tides rise quickly, and keep well back from seals and roosting birds.

Look for

Harbour Seal
Red Knot
Eurasian Oystercatcher
Common Eider
Barnacle Goose

Often a good time to visit: April, May, August, September, October. Conditions vary from year to year and place to place.

Related habitats

Coastal · Wetland