摘要：350000–400000 pairs of breeding birds as well as 10–12 millions of migratory waterbirds use the Danish-German-Dutch Wadden Sea as a feeding, roosting and moulting area. The exact number of migrating birds using the Wadden Sea is unknown. 4 Wadden Sea breeding bird species are (probably) extinct in the area, e.g. Caspian Tern (Sterna caspia) and Roseate Tern (Sterna dougallii); the status of 5 species is critical, 4 species are endangered, the status of 6 species is vulnerable and of 4 species susceptible. Internaional responsibility can be stated for at least 15 breeding bird species or subspecies, because considerable parts of the north-west-european population (at least 5%) breed in the Wadden Sea (e.g. Eurasian Spoonbill (Platalea leucorodia), Common Shelduck (Tadorna tadorna), Hen Harrier (Circus cyaneus), Avocet (Recurvirostra avosetta), Kentish Plover (Charadrius alexandrinus), Common Redshank (Tringa totanus totanus), Gull-billed Tern (Gelochelidon nilotica), Sandwich Tern (Sterna sandvicensis), Common Tern (Sterna hirundo), Little Tern (Sterna albifrons). International responsibility can be determined for at least 54 migratory bird species or subspecies, because considerable parts of the biogeographical population (at least 1%) occur in the Wadden Sea during migration. Some species are present in the Wadden Sea with about 50% or nearly 90% of all individuals of the concerned populations, which means a very special international responsibility of the Wadden Sea has to be stated for these species.
关键词：Common Tern;Kentish Plover;Sandwich Tern;Migratory Bird Species;Breed Bird Species
