Usually treated as a subspecies of M. fusca or as conspecific with M. stejnegeri if separated from M. fusca, but here treated as a species in its own right (following recent study#R). Male differs from male fusca in its bill protuberance and forehead being relatively high (morphometric character gauged as 2); red-sided yellow-centred (often with yellow barely visible) vs all-yellow upper mandible (2); feathering around bill protuberance extending forward and down, then cutting away sharply, leaving panel of feathers at base of upper mandible vs cutting back and away, creating no side-panel of feathering (3); greatly increased black on base of upper mandible (so yellow extends back under “lores”) (2); flanks dark brown vs all black (ns); longer-tailed subocular eye-patch (ns). For differences from M. stejnegeri see under that species. Birds of W Alaska occasionally separated as race dixoni. Monotypic.
Breeds in Alaska and Canada E to Hudson Bay. Winters along W coast from W Aleutian Is S to Baja California; and along E coast from Gulf of St Lawrence S to N Florida.
Food and feeding
Status and conservation
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