American Goldfinch - Spinus tristis

American Goldfinch has a partial preformative molt and a partial prealternate molt. Sex can generally be identified by plumage throughout the year, although the difference between males and females is more subtle in winter and as juveniles.

Age and plumage cycle can usually be determined reliably throughout the year. However, caution is required from late summer to mid-fall (primarily August to October), when the prejuvenile, preformative, and prebasic molts of individuals in a population may overlap. During this period, four age classes (HY, SY, AHY, ASY), four active molt categories (FPJ, FPF, SPB, and DPB), and five plumage categories (FCJ, FCF, FCA, DCB, and DCA) may be possible concurrently. The presence of alternate plumage (e.g., black cap and bright yellow body on males) and the extent of feather wear are particularly important clues during this period.

Consejos claves

• Compare the primary and greater coverts. In FCF (HY/SY) and FCA (SY) individuals, the black (male) or dark brown (female) greater coverts contrast with the paler and more worn primary coverts (as well as primaries and secondaries), compared to DCB (AHY/ASY) and DCA (ASY) individuals, which have wings that are largely uniformly blackish (male) or dark brown (female), and FCJ (HY) individuals, which have wings that are uniformly brownish.
• Examine the tail. In FCF (HY/SY) and FCA (SY) individuals, outer rectrices are generally somewhat tapered and dark brown to blackish (male) or grayish-brown (female) with somewhat distinct whitish patches (male) or indistinct pale patches (female), compared to DCB (AHY/ASY) and DCA (ASY) individuals, which typically have broader outer rectrices that are black (male) or dark brown (female) with sharply delineated white (male) or fairly distinct whitish (female) patches.
• Consider overall appearance. In FCA (SY) and DCA (ASY) individuals, body plumage is primarily yellow, with (males) or without (females) a black cap, compared to all other ages, which have predominantly beige body plumage.

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