Distribution / Range
Parasitic Jaegers breed in the north of Eurasia and North America, with significant populations as far south as northern Scotland. In the British Isles, they nest in Shetland and Orkney, the Outer Hebrides, Sutherland, Caithness and various islands in Argyll. These migrants spend the winters at sea in the southern oceans and the tropics.
The Parasitic Jaeger measures about 41 cm in length, not including the pointed central tail feathers of the breeding adult.
Light phase adults: Back is brown, The underparts are mostly white. The primary wing feathers are dark with a white "flash." The neck and the head is yellowish-white with a black cap.
Dark phase adults: Plumage is dark brown.
Intermediate phase adults: Dark plumage with paler underparts, head and neck.