posted May 1st, 2012; last edited August 20th, 2012 –– David Sibley

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.

11 comments to The annual plumage cycle of a male American Goldfinch

  • David, I’m glad you enabled the slideshow feature. I showed it to my adult school birding class and they absolutely loved it. We all think that molt sequences like this should be included in the next update of your iPhone, iPad app, as well as your next edition of the printed guides…. no pressure. Thanks again for a great job!

  • David, This post is brilliant. I love watching the wing feathers come in and then wear down. Thank you. You inspire me in both my art and observation.

  • Eric Wenocur

    Very helpful, I was just wondering about this! Right now the goldfinches at our feeder are so striking, but we knew it won’t last…

  • David, as I cursor through the images in a slideshow format, I see what looks like 2 or three base images probably arranged in layers, and a series of photoshop masks between them used to reveal intermediate colors and patterns between them. Is that how you created the monthly steps in the year-long molt series? If so, it’s a very effective technique. Thanks, Matthew

  • Lucy Davis

    David,
    I have been a city girll all my life moved to the county just 6 years ago first thing that attracted me was all the beautiful birds. One of my favorites have been the Goldfinch’s. I just recently found out that they actully don’t leave they change color in the winter! Found your site I learned so much thank you for inspiring more.

  • Is there any genetic basis for the change in feather color or does this result solely based on the environmental surroundings? I am trying to determine if this is considered an adaptation or if it is an example of phenotypic plasticity.
    For explanation on the difference, see: http://evolution.berkeley.edu/evolibrary/news/090501_climatechange
    Seeking Clarification,

    HS Science Teacher
    Eileen Ulry
    eulry@ohva.org

    • Hi Eileen, This seasonal color change is mainly genetic, an adaptation that allows the males to show off bright colors to females. The pigments in their feathers are carotenoids that are directly linked to immune system functions. Therefore a healthy male that has a lot of carotenoids to spare will grow nice bright feathers, and color is an “honest” signal of health.

      Goldfinches, like most small songbirds, molt twice each year. The molt itself and the difference in color between breeding and nonbreeding plumage is genetically programmed, but the “trigger” that determines whether the new feathers will grow in bright or drab is hormonal.

      I hope that makes sense and answers your question.

      Best, David

  • Eileen Ulry

    Thanks so much for your expertise, David!

  • ginny matthews

    David, I live in Georgia and enjoy goldfinches greatly. One observation I have made is a very small yellow spot at the base of the tail in late winter. These birds look like goldfinches, yet I am unsure. I would love to supply a photograph, but alas, I have been unsuccessful.Please advise if possible.

    Ginny Matthews
    .

  • Mo

    David,
    I noticed a big change at my feeders over the weekend all of a sudden there is less activity. My orioles I assume have left for warn climes. May I assume the absence of my goldfinches is they are molting? We’ve also had terribly rainy, stormy weather could it be a combination of those two factors ? I sure am missing seeing all the birds every morning!

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