Long-tailed Jaeger
Skua ( Stercorarius longicaudus )
The Skua ( Stercorarius longicaudus ) is a type in the family of skuas. There are two subspecies. In Central Europe it is a rarer than the Skua and the Pomarine. However, between 1991 and 1996 alone 432 individuals of this species have been observed in Belgium.
Appearance
The upper part of the head and neck are glossy black. The chest and the neck are white, the latter has a yellowish tinge. The back and wings are colored brown green surface. Furthermore, falls on a pronounced long tail. With a length of 40 to 55 centimeters and weighing from 220 to 350 grams, it is the smallest species of skuas.
Dissemination
The Skua breeds in the Arctic regions of Eurasia and North America. In Alaska and northern Russia, they are somewhat more common than in the rest of the Arctic. It breeds in the dry tundra, searching also breeding grounds and are remote from the coast. The European breeding population is estimated at 12000-78000 breeding pairs. The European part of Russia has with 10,000 to 50,000 breeding pairs on the largest inventory. Breed on Greenland 1000-20000 breeding pairs. In Fennoscandia about 600-8000 breeding pairs live.
Outside the breeding season the Skua is an outspoken seabird. The wintering areas in the southern Atlantic and Pacific. In the North Atlantic they wintered only in exceptional cases. The flyway in these wintering areas is not fully understood. Probably pull the Western Palaearctic breeding birds initially to the North Atlantic and from there to a greater distance of the coast to the south. Migratory birds are seen over the North Atlantic, especially in late August and early September. Off the coast of Namibia Skua hold on at the end of September. From the end of March, they pull back to their breeding grounds, the earliest they reach the end of May. For Falk skuas a Brutorttreue is detected.
Food
In the breeding areas, the seagulls typical Beuteabjagen hardly plays a role in the long-tailed skua. Their diet consists mainly of bank voles here, voles, and similar small mammals. They also eat insects, eggs and small birds here. It also accepts berries as food additive in smaller quantities. On the coast it eats mostly self- caught fish, crustaceans and cephalopods.
Stock Projection
The Skua is one of the species that will be particularly affected by climate change. A research team that examined the future diffusion trend of European breeding birds on the basis of climate models for the UK Environment Agency and the Royal Society for the Protection of Birds, expects that by the end of the 21st century, the area of distribution of skua will shrink considerably. Large parts of today's breeding grounds in Norway and Sweden will provide this type then no suitable habitats more. Possible new areas of distribution arise on Franz Josef Land and Novaya Zemlya mainly on, but can not compensate for the potential area earnings complex losses.