Shorebirds, which raise millions of offspring during a very short breeding season in the Arctic tundra, are an excellent example of a highly specialized migratory species. Among them is the Bar-tailed Godwit, which makes the longest known non-stop flight of any bird and also the longest journey without pausing to feed by any animal, 11,680 kilo- metres along a route from Alaska to New Zealand. Within the East Asian-Australasian Flyway the tidal flats of the Yellow Sea are the most important refueling sites ("airport" for birds). The huge embankment of Saemangeum, which enclosed 400 km2 of tidal flats have decreased important refueling space for Arctic shorebirds significantly.