Larus glaucescens

The Glaucous-winged Gull is a large gull of the North Pacific coast. Adults have a pale grey back and wingtips that are about the same colour rather than black. It eats fish, marine invertebrates, carrion, eggs and human refuse. The species breeds in colonies on islands, cliffs and rooftops. Around Washington and Oregon it hybridises extensively with the Western Gull, producing many intermediate birds.
Locations where this species is supported by a dated first record, an unambiguous single-place outing or a reviewed assignment.