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,
Fork-tailed storm petrel their tail. The fork-tailed storm petrel is a part of the tubenose order Procellariformes and family Hydrobatidae. The genus "Oceanodroma" arises from Ancient Greek "okeanos dromos", meaning "ocean runner", reflecting the storm petrel's distinct foraging style. Their specific name "furcata" is Latin for branched or forked, derived from "furcatus", referring to their characteristic forked tail. 2 subspecies are recognized: The major differences between the two subspecies are slight size and plumage differences, where southern populations appear somewhat smaller and darker. Southern populations also begin and end the breeding season earlier than their northern counterparts. However, no molecular genetic analysis has