Nashville Warbler - Oreothlypis ruficapilla

Nashville Warbler has a partial preformative molt that occurs primarily before migration or at a molt-migration stopover site, and a limited prealternate molt that is restricted to the head. Most Nashville Warblers can be aged and sexed by plumage, but some differences are relatively subtle, and especially to distinguish between FCF/FCA (HY/SY) males and DCB/DCA (AHY/ASY) females, checking multiple criteria is advised.

Quick tips

• Consider the face - DCB/DCA (AHY/ASY) males have a distinct white eye ring contrasting with a blue-gray background, DCB/DCA (AHY/ASY) female and FCF/FCA (HY/SY) males have a whitish to white eye ring on a dull gray background, and FCF/FCA (HY/SY) females have a dull buffy to whitish eye ring on an olive-gray background.
• Examine the crown patch (often partly to entirely concealed at rest) - on DCB/DCA (AHY/ASY) males it is large and deep rufous; on FCF/FCA (HY/SY) males it is rufous but moderate in size, on DCB/DCA (AHY/ASY) females it is moderate in size but pale rufous, and on FCF/FCA (HY/SY) females it is small and pale rufous if present at all.
• Look at the tail - on FCF/FCA (HY/SY) birds the rectrices tend to be fairly narrow, pointed, and by spring often pale brownish; on DCB/DCA (AHY/ASY) birds they are relatively broad and rounded at the tip, and typically darker and fresher in appearance.
• Check the wing for a molt limit on FCF/FCA (HY/SY) individuals either between brownish primary and greenish greater coverts, or among the outer greater coverts; DCB/DCA (AHY/ASY) birds have a more uniformly olive-green wing.

Species account prepared by McGill Bird Observatory (2016). Last updated by Marcel Gahbauer (Mar 2022)