Wadden Sea
Intertidal zone with rich bird life and UNESCO World Heritage status.
The Wadden Sea is an intertidal zone in the southeastern part of the North Sea, lying between the coast of northwestern continental Europe and the range of low-lying Frisian Islands. It is a shallow body of water with tidal flats and wetlands, noted for high biological diversity and importance for breeding and migrating birds. In 2009, the Dutch and German parts were inscribed on UNESCO's World Heritage List, with the Danish part added in 2014.
- Location
- Southeastern North Sea, between Netherlands, Germany, and Denmark
- Length
- Approximately 500 km (310 mi) of coastline
- Area
- About 10,000 km² (3,900 mi²)
- UNESCO World Heritage inscription
- 2009 (Dutch and German parts); Danish part added 2014
- Key feature
- Extensive tidal mud flats, tidal creeks, and Frisian Islands
- Major threats
- Sea level rise, invasive species, human alteration
Lore & Background
The Wadden Sea stretches from Den Helder in the Netherlands past German river estuaries to Skallingen in Denmark. Historically, coastal regions suffered large floods, including the Saint Marcellus' floods of 1219 and 1362, the Burchardi flood of 1634, and the Christmas Flood of 1717, which caused thousands of deaths and changed coastlines. Dikes and causeways have since been built, making it among the most human-altered habitats on the planet. The landscape was largely formed by storm tides in the 10th to 14th centuries that overflowed peat land behind coastal dunes; the present islands are remnants of those dunes.
Reader's Guide
The Wadden Sea is significant as a UNESCO World Heritage site and a critical habitat for hundreds of thousands of waders, ducks, geese, gulls, terns, and birds of prey, including a small breeding population of white-tailed eagles. It also supports harbour and grey seals, harbour porpoises, and white-beaked dolphins. However, biodiversity has declined due to human activity and environmental change; species such as the European oyster have been extirpated, and invasive Pacific oysters now form large beds. The region is protected through trilateral cooperation among the Netherlands, Denmark, and Germany, with a Joint Declaration in 1982 and a Trilateral Wadden Sea Plan in 1997. It was declared a UNESCO biosphere reserve in 1986. Mudflat hiking and pleasure boating are popular recreational activities.
Did You Know?
- The word 'wad' is Frisian and Dutch for 'mud flat'.
- The islands of Vlieland and Ameland have moved eastward over centuries due to wave and current action.
- The world's only remaining natural population of houting survives in the Danish part of the Wadden Sea.
- A possible North Atlantic right whale was observed close to beaches on Texel in the West Frisian Islands in July 2005.
More in Straits, Channels, And Seas 1-24
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