Sabine's Gull is an unusual and distinctive arctic gull that breeds at high latitudes but winters in coastal upwelling zones of the Tropics and Subtropics. Its dark gray hood, black bill with yellow tip, and tricolored upperwing consisting of alternating triangles of black, white, and gray make the adults of this species highly identifiable.
First discovered at Melville Bay, Greenland, by Edward Sabine, in 1818 ( Sabine 1819 ), this Holarctic, high-arctic species nests on arctic and subarctic tundra in marshy areas, often with extensive mixtures of marshes, ponds, and lakes. Females lay 2–3 eggs in rudimentary nests, often without nest-lining, and incubate them for 20–25 d; after hatching, the young are taken to freshwater ponds or saltwater shorelines, where they grow rapidly while feeding on aquatic insects, especially dipterans. After breeding, both adults and young migrate to winter at sea in coastal-upwelling zones off western South America and southern Africa.
The Sabine's Gull is considered an aberrant gull, both morphologically and behaviorally ( Brown et al. 1967 , Abraham 1986 ). It is one of only two gulls having a black bill with a yellow tip and a notched tail. It also displays many behavioral characteristics more similar to shorebirds than to gulls (e.g., distraction display, feeding method on mudflats) and others more similar to terns than to gulls (e.g., call, flight, feeding of whole prey directly to female during courtship, development of flight long before chick is fully feathered).
The primary research on Sabine's Gulls has been on behavior ( Brown et al. 1967 ), breeding biology ( Sutton 1932b , Brandt 1942 , Parmelee et al. 1967 , Abraham 1986 , Forchhammer and Maagaard 1991 , Stenhouse et al. 2001 ), and feeding ecology and habitat use (Duffy Duffy 1983d , Duffy 1989 ; Abraham and Ankney 1984 ). Much, however, remains to be learned about most aspects of the ecology of this unique little gull.