American Herring Gull (smithsonianus)

(last update: October 30, 2015)

Amar Ayyash (US)
Bruce Mactavish (Canada)
Dave Brown (Canada)
Mars Muusse (Netherlands)

Glaucous-winged Gull x American Herring Gull adult, December 30 2011, Tukwila, WA. Picture: Amar Ayyash.

Glaucous-winged is known for its hybrids with Western Gull (so-called Olympic Gulls), but there also seem to be no shortage of Glaucous-winged x Herring Gulls (so-called Cook Inlet Gulls). These Cook Inlet Gulls tend to show smaller bills than Olympic Gulls.