Tennessee Warbler - Leiothlypis peregrina

Tennessee 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 and throat. Older (definitive cycle) males are often readily recognizable by their overall plumage, but other age/sex classes can be more difficult to determine reliably, and may require consideration of multiple features.

Quick tips

• Look at the crown and nape - on DCB/DCA (AHY/ASY) males the blue-gray crown contrasts sharply with the green nape, on FCA (SY) males the gray crown contrasts distinctly with the green nape, on DCB/DCA (AHY/ASY) females the grayish-green crown contrasts only slightly with the nape, and on FCF (HY) birds and FCA (SY) females the crown and nape are almost uniformly dull grayish-green.
• Examine the tail - on FCF/FCA (HY/SY) birds the rectrices tend to be fairly narrow and pointed and generally lacking white; on DCB/DCA (AHY/ASY) birds they are relatively broad and rounded at the tip, and the outermost 1-2 feathers may have some white near the tip.
• Look at the primary coverts - on FCF/FCA (HY/SY) birds they tend to be narrow and generally somewhat paler or browner than the greater coverts; on DCB/DCA (AHY/ASY) birds they are relatively broad and uniformly green with the greater coverts.
• Consider the colour of the underparts - in spring and summer, DCA (ASY) males are almost entirely white, while FCA (SY) males and DCA (ASY) females usually are whitish with some yellow tinges, and FCA (SY) females have a faint yellowish tone overall; in fall, DCB (AHY) males are whitish with a yellowish tinge, while all others are primarily yellowish.

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