[order] CHARADRIIFORMES | [family] Stercorariidae | [latin] Stercorarius skua | [UK] Great Skua | [FR] Grand Labbe | [DE] Skua | [ES] Pagalo Grande | [NL] Grote Jager
Subspecies
Monotypic species
Physical charateristics
A large, dark, heavy-bodied, gull-like bird, mottled gray-brown with conspicuous white patches on the outer wing. Tail short and blunt. Immatures of larger gulls lack prominent white wing patches.
Listen to the sound of Great Skua
[audio:http://www.aviflevoland.nl/sounddb/G/Great Skua.mp3]
Copyright remark: Most sounds derived from xeno-canto
| wingspan min.: | 125 | cm | wingspan max.: | 140 | cm |
| size min.: | 50 | cm | size max.: | 58 | cm |
| incubation min.: | 26 | days | incubation max.: | 32 | days |
| fledging min.: | 40 | days | fledging max.: | 32 | days |
| broods: | 1 | eggs min.: | 1 | ||
| eggs max.: | 2 |
Range
Eurasia : Northwest islands and coasts
Habitat
Breeds on open bare ground near the sea; at other times, ranges over the ocean.
Reproduction
Great Skuas nest on coastal moorland, often in loose groups of scattered nests, but with some colonies numbering thousands of pairs. When nesting at low density in small colonies, most birds in the colony feed by killing birds. However, when nesting in large colonies, the majority feed on fish, including fishery discards, and only a small proportion specialize in killing seabirds. Ringing has shown that Great Skuas from Shetland have emigrated to form colonies in many other areas as far away as north Russia, but the majority of chicks return to their natal colony to try to establish a breeding territory. 2 olive-brown eggs, with dark brown spots, in a grass-lined nest on the ground. Often nests in loose colonies. Incubation lasts 26-27 days. Fledging period 26-30 days. Breeds at three or more years.
Feeding habits
Often nests close to other seabirds, where it obtains all its food from piracy or by preying on lemmings and the eggs and chicks of heterospecifics. In winter normally aggregates with other seabirds from whom it pirates.
Conservation
This species has a large range, with an estimated global breeding Extent of Occurrence of 50,000-100,000 km2. It has a large global population estimated to be 10,000-20,000 individuals (del Hoyo et al. 1996). Global population trends have not been quantified, but there is evidence of a population increase (del Hoyo et al. 1996), and so the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e. declining more than 30% in ten years or three generations). For these reasons, the species is evaluated as Least Concern.
Migration
North Atlantic population migratory; pelagic outside breeding season and during years of immaturity. Total marine range extends from Greenland and Norwegian Sea south at least to Brazil and outer Gulf of Guinea, but southern limits poorly known due to presence of South Polar Skua in South Atlantic (some moving north in southern winter). Probably achieves maximum dispersion in 3rd year of life, including marked tendency to occur in summer well north of natal areas (Greenland, Iceland, Faeroes, Norway). From 5th year onwards, starts showing summer attachment to colony; much reduced tendency to visit northern latitudes or (in winter) to be found in seas south or south-west of Europe. More stable migration pattern established with attainment of maturity.
Distribution map
