A winter pelagic species - for those who like doing winter pelagics! Mind you, I can think of worse places than the coast of Portugal for partaking of this particularly nauseous activity, and Great Skuas can sometimes be observed harassing Gannets and other sea-going species.
Overall this species is a dark brown bird, but the base of the primaries are white and this shows up as a white flash towards the end of the wing; Pomarine Skuas and juvenile Arctic Skuas show the same diagnostic feature, but both are considerably smaller.
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