Scarce high-Arctic breeder. Typically migrates far offshore, but some close to shore or inland lakes, particularly in Sep. Few winter records. A beautiful gull with tern-like qualities and striking upperwing made of triangular patterns. Forked tail seems to have limited use. Often mistaken for larger and broader-winged juv BLKI, which also has narrower and poorly-defined 'M' pattern. Ad br: black-bordered gray hood. Pale-tipped black bill. Keeps dark hood into fall. 2nd-s: as nonbr with heavily worn flight feathers. Juv: brown replaces areas of gray in adult. Color can be difficult to judge at distance. Darker neck and black tail band.