Range Description: Thayer's Gull - Larus thayeri

Summary of the extent of the breeding, wintering, migration and year-round range of this species in the Western Hemisphere, including Canada, U.S.A. and Mexico:

Canada - Breeding only: 902,345 square km; Wintering only: 319,654 square km; Migration only: 177,999 square km
Mexico - Wintering only: 145,301 square km
U.S.A. - Wintering only: 784,932 square km