The annual plumage cycle of a male American Goldfinch

Molt is the process of feather replacement. All birds do it; they have to grow new feathers once or twice a year to stay warm, dry, and airborne, and in many cases they grow differently colored feathers at different seasons to match their surroundings or to impress others of their species.

Among the small songbirds, virtually all species have a complete molt (replacing all of their feathers) in late summer, and in addition many species have a partial molt (replacing some of the body feathers but not the wing or tail feathers) in the spring.

American Goldfinch follows this pattern. Beginning in September, and continuing for six to eight weeks, they molt all of their feathers, ending up with a completely new and pristine set of feathers (and drab colors) as they head into the winter. In the spring, as they grow new body feathers the males especially transform into bright yellow breeding plumage, but the wing and tail feathers remain from the previous fall. As these wing feathers get older the pale buff edges fade to white and disintegrate, so that by the end of the summer the wings look essentially all black. And in September another complete molt begins.

Watch the slideshow, click the thumbnails, or click on the main image to advance, and see what other patterns you can notice.

PausePlayPlayPrev|Next

Related posts and pages:

• Juvenal plumage of songbirds: Gray Catbird Most Passerines only hold juvenal plumage for a few weeks, quickly molting to a more...
• The mystery of the orange-throated hummingbirds An orange-throated male Ruby-throated Hummingbird seen in late August 2009 in Virginia. Photograph copyright Masaharu...
• The changeable shape of the supercilium The feathers that grow on the sides of the head above the eyes of a...
• Determining the age of white egrets and herons in late summer A field sketch from South Carolina, showing the differences in feather shapes and patterns between...
• Identification of the Martha’s Vineyard Red-footed Falcon Illustration of the Red-footed Falcon perched. The smooth gray color is unlike any North American...
• Variation in immature Ring-billed Gulls On October 9th, 2005 I was enjoying the view at First Encounter Beach in Eastham,...
• Orange-throated Hummingbirds: more questions Now updated by a new post Progress on the Orange-throated hummingbird mystery. This adds to...
• Quiz 12: More on head feathers A teaser of spring wood-warblers on this bonus day of February. Two questions for each...