The Red Knot is breeding with 6 subspecies in the circumpolar high Arctic tundra. Calidris canutus islandica is breeding in the barren lands of North Greenland and North-East Canada. In the very short high Arctic summer the young knots benefits from the abundance of insects, such as big specimen of Tipula, and grow very fast. During other parts of the year, when they winter in Western Europe and stage in the Wadden Sea, Northern Norway and Iceland they depend on tidal mudflats and small shellfish for feeding. On the way to the breeding areas in Northern Greenland and North-East Canada the Porsanger Fjord and Iceland serve in May as the most important staging (refueling) area between the Wadden Sea and the High Arctic.