The Molt of the American Goldfinch

Abstract

The annual molt was studied in 3633 American goldfinches [carduelis tristis] collected for gonadal study or banding between 1967-1975, and from 13 captive birds used for breeding in 1971 and 1972. The postnuptial molt is similar to that described for most cardueline finches and for passerines in general. However the goldfinch proved unique among carduelines in the acquisition of its breeding plumage by a prenuptial body molt. In addition, the prolonged period required to complete both the prenuptial and postnuptial body molts is unusual for a temperate zone passerine. The presence of the prenuptial molt may have some relationship to late nesting by the goldfinch. The prolonged body molts may be necessary adaptations which permit the highly granivorous goldfinch to meet the energetic demands of molt.