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,
Ivory gull Ivory gull The ivory gull ("Pagophila eburnea") is a small gull, the only species in the genus Pagophila. It breeds in the high Arctic and has a circumpolar distribution through Greenland, northernmost North America, and Eurasia. The ivory gull was initially described by Constantine Phipps, 2nd Baron Mulgrave in 1774 as "Larus eburneus" from a specimen collected on Spitsbergen. Johann Jakob Kaup later recognized the unique traits of the ivory gull and gave it a monotypic genus, "Pagophila", in 1829. Johan Ernst Gunnerus later gave the species a new specific name, "Pagophila alba". The genus name "Pagophila" is from Ancient