Sabine's gull steals eggs from nesting colonies of Arctic terns. The Sabine's gull is a small gull, in length and weighing . The wings are long, thin and pointed with a span of between . The bill, which is black with a yellow tip, is around long. This species is easy to identify through its striking wing pattern. The adult has a pale grey back and wing coverts, black primary flight feathers and white secondaries. The white tail is forked. The male's hood darkens during breeding season. Young birds have a similar tricoloured wing pattern, but the grey is replaced by brown,
Glaucous gull Glaucous gull The glaucous gull ("Larus hyperboreus") is a large gull, the second largest gull in the world, which breeds in Arctic regions of the Northern Hemisphere and winters south to shores of the Holarctic. The genus name is from Latin "Larus", which appears to have referred to a gull or other large seabird. The specific "hyperboreus" is Latin for "northern" from the Ancient Greek "Huperboreoi" people from the far north "Glaucous" is from Latin "glaucus" and denotes a bluish-green or grey colour. This gull is migratory, wintering from in the North Atlantic and North Pacific oceans as far south