The skuas are a group of predatory seabirds with seven species forming the genus Stercorarius, the only genus in the family Stercorariidae. The three smaller skuas, the Arctic skua, the long-tailed skua, and the pomarine skua, are called jaegers in North American English.
Skua
Two brown skuas (S. antarcticus) and a southern giant petrel (Macronectes giganteus) fighting over a dead Antarctic fur seal
Great skua leaving the nest
Skua nestling, with egg tooth still present on its beak
Seabirds are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations. The first seabirds evolved in the Cretaceous period, and modern seabird families emerged in the Paleogene.
The sooty tern is highly aerial and marine and spends months flying at sea, returning to land only for breeding.
The Cretaceous seabird Hesperornis
Cormorants, like this double-crested cormorant, have plumage that is partly wettable. This functional adaptation balances the competing requirement for thermoregulation against that of the need to reduce buoyancy.
Wilson's storm petrels pattering on the water's surface
