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Ecosystem

Wadden Sea

VAH-den
Also Known As Waddenzee The Dutch name for the same site. · Wattenmeer The German name for the same site.
Wetland and Freshwater
Wadden Sea

The largest unbroken system of intertidal sand and mud flats in the world, a band of channels, tidal flats, salt marshes and barrier islands running along the North Sea coast of the Netherlands, Germany and Denmark. Twice-daily tides expose and reflood roughly half the ecosystem's area, and the vast biomass of worms, shellfish and other invertebrates living in the exposed flats makes the Wadden Sea one of the most important staging and wintering grounds on the East Atlantic Flyway, hosting more than ten million migratory shorebirds and waterbirds in an average year. The Netherlands and Germany jointly inscribed the site as a UNESCO World Heritage property in 2009, extended to the Hamburg Wadden Sea in 2011 and to the Danish Wadden Sea in 2014, bringing the full trilateral site to roughly 11,500 square kilometers.

Facts
Area (sq km)
11,500 1
The formal UNESCO World Heritage property is cited at approximately 11,434 to 11,500 square kilometers; some sources describe the broader trilateral wadden region, outside the strict World Heritage boundary, at closer to 10,000 square kilometers.
Classification
Biogeographic Realm
Palearctic 1
Protected Status
Managed or Multiple-Use Protection 1
Connections

Demonstrates

Source UNESCO World Heritage Centre
Source UNESCO World Heritage Centre

Hosts

Source Barnacle goose (Wikipedia)
Source Bar-tailed godwit (Wikipedia)
Blue Mussel, Species
Source Wikipedia: Blue mussel
Source Buccinum undatum (Wikipedia)
Source Common shelduck (Wikipedia)
Common Whelk, Species
Source Buccinum undatum (Wikipedia)
Source Wikipedia: European Anchovy
Source Wikipedia: Guillardia
Source Harbour porpoise, Wikipedia
Source Wikidata: Pacific Oyster
Additional Source Wadden Sea (Wikipedia)Article text
Source Red knot (Wikipedia)
Source Soft-shell clam (Wikipedia)
Source White-tailed eagle (Wikipedia)
Source Zostera marina (Wikipedia)

In Biome

Marine, Biomes

An intertidal, saline system at the boundary of marine and freshwater river influence; classified here under the Marine biome for its dominant tidal and saline character.

Source UNESCO World Heritage Centre
In the Other Atlases

Same As

Also in Geography Atlas: the same subject.

Found In

Also in Geography Atlas: where this subject is found.

Also in Geography Atlas: where this subject is found.

Also in Geography Atlas: where this subject is found.

Sources
1. UNESCO World Heritage Centre
UNESCO World Heritage Centre
  • World Heritage List entry 1314, site description
    The Wadden Sea is the largest unbroken system of intertidal sand and mud flats in the world.
  • Biogeographic realm: palearctic (derived from location stated in entity description)
  • Protected status (stated plainly in the entity own recorded description)
    The Netherlands and Germany jointly inscribed the site as a UNESCO World Heritage property in 2009, extended to the Hamburg Wadden Sea in 2011 and to the Danish Wadden Sea in 2014, bringing the full trilateral site to roughly 11,500 square kilometers.
  • In Biome: Marine
  • In Category: Ecosystems
  • Demonstrates: Tides
  • Demonstrates: Migration
View the Source
Soft-shell clam (Wikipedia)
Hosts: Soft-shell clam, Habitat and distribution
Quote, Hosts: Soft-shell clam, Habitat and distribution
They are also found in the Eastern Atlantic Ocean, for example in the UK, as well as in the North Sea's Wadden Sea (where they are the dominant large clam).
View the Source
Harbour porpoise, Wikipedia
Hosts: Harbour Porpoise, Description
Quote, Hosts: Harbour Porpoise, Description
Many anomalously white coloured individuals have been confirmed, mostly in the North Atlantic, but also notably around Turkish and British coasts, and in the Wadden Sea, Bay of Fundy and around the coast of Cornwall.
View the Source
Wikipedia: Blue mussel
Hosts: Blue Mussel, Predators
Quote, Hosts: Blue Mussel, Predators
Predation of blue mussels is greatest during the three weeks it spends as a planktonic larva.
View the Source
Buccinum undatum (Wikipedia)
  • Hosts: Common Whelk, Ecology and population decline
    Disappearing or diminishing populations of whelks have been observed since the early 1970s, especially in the North Sea and the Wadden Sea.
  • Hosts: Buccinum undatum, Ecology and population decline
    Disappearing or diminishing populations of whelks have been observed since the early 1970s, especially in the North Sea and the Wadden Sea.
View the Source
Wikipedia: European Anchovy
WikipediaHosts: European Anchovy, Zuiderzee and English Channel
Quote, Hosts: European Anchovy, Zuiderzee and English Channel
After the closing of the Zuiderzee they were still found in the Wadden Sea until the 1960s.
View the Source
White-tailed eagle (Wikipedia)
Hosts: White-tailed eagle, Wintering range
Quote, Hosts: White-tailed eagle, Wintering range
In Denmark, they both breed and winter throughout much of the country, but in particular the Wadden Sea region attracts many white-tailed eagles, mostly immatures, from elsewhere in Denmark and neighbouring countries during the winter.
View the Source
Bar-tailed godwit (Wikipedia)
Hosts: Bar-tailed Godwit, Food and feeding
Quote, Hosts: Bar-tailed Godwit, Food and feeding
In another study in the Wadden Sea, females primarily ate lugworms and ragworms while males relied almost exclusively on mud shrimps.
View the Source
Barnacle goose (Wikipedia)
Hosts: Barnacle goose, Distribution and population size
Quote, Hosts: Barnacle goose, Distribution and population size
Breeding on Novaya Zemlya, Dolgy Island, Kanin Peninsula, Yugorsky Peninsula and the Barents Sea coastline in the Russian Arctic, wintering in the Wadden Sea area in southwest Denmark, northwest Germany and the Netherlands.
View the Source
Common shelduck (Wikipedia)
Hosts: Common shelduck, Distribution and habitat
Quote, Hosts: Common shelduck, Distribution and habitat
Asian populations migrate to subtropical areas in winter, south to northern India and southern China, but this species is largely resident in Europe, apart Scandinavian and some eastern European populations which migrate southwest, and from movements to favoured late summer moulting grounds, such as the Wadden Sea on the north German coast.
View the Source
Zostera marina (Wikipedia)
Hosts: Zostera marina, Threats
Quote, Hosts: Zostera marina, Threats
Human activities such as dredging and trawling damage eelgrass meadows; practices used in scallop and mussel harvesting in the Wadden Sea have cleared much eelgrass from the sea bottom there.
View the Source
Wadden Sea (Wikipedia)
Hosts: Pacific Oyster, Article text
Quote, Hosts: Pacific Oyster, Article text
European oyster once formed large beds in the region and was still present until a few decades ago, when extirpated due to a combination of disease and the continued spread of the invasive Pacific oyster, which now forms large beds in the Wadden Sea.
View the Source
Wikipedia: Guillardia
WikipediaHosts: Guillardia Theta, Distribution and habitat
Quote, Hosts: Guillardia Theta, Distribution and habitat
Larsen is the only other researcher to have identified Guillardia in the wild within the Wadden Sea in Denmark.
View the Source
Red knot (Wikipedia)
Hosts: Red Knot (Calidris canutus), Distribution and habitat
Quote, Hosts: Red Knot (Calidris canutus), Distribution and habitat
In temperate regions such as the Wadden Sea they have been found to change roost sites each week and their feeding range may be as much as 800 km2 (310 sq mi) during the course of a week.
View the Source

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