Bahamas, Belize, Bermuda, Canada, Cayman Islands, Colombia, Costa Rica, Cuba, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Puerto Rico, St Pierre and Miquelon (B) (P), Turks and Caicos Islands, USA (B).
Vagrant to Greenland, Haiti, Jamaica, United Kingdom.
Population
Estimated population is 40,000,000 (2010).
Wilson's Warbler (Cardellina pusilla) [XC406217]
by Frank Lambert from Nome, Nome Census Area, Alaska, United States (song)
Wilson's Warbler (Cardellina pusilla) [XC752979]
by Manuel Grosselet from John Prince Research Forest, Canada (song)
Subspecies
Relationship with congeners not clear.
The following 3 subspecies are recognised:
pileolata (Pallas, 1811) - Breeds northern Alaska southern along coast to central British Columbia, including Queen Charlotte Is, also in western USA southern in Rockies to northern New Mexico and in coastal mountain ranges to central California; migrates to region from north-western Mexico south to western Panama.
pusilla (Wilson, 1811) - Breeds central and southern Canada (Mackenzie District of Northwest Territories and northern Alberta east to Newfoundland and Nova Scotia) and north-eastern USA (New England); migrates to region from eastern Mexico south to Costa Rica, also extreme southern USA (extreme south-eastern Texas and south-western Gulf coast).
chryseola (Ridgway, 1902) - Breeds Pacific coast and western slope of coastal mountain ranges from south-western British Columbia south to southern California; migrates to region from north-western Mexico (including Baja California) south to Panama.