About us: We own the Wild Birds Unlimited nature shop in East Lansing, Michigan,
a store that provides a wide variety of supplies to help you enjoy the birdwatching hobby.

This blog was created to answer frequently asked questions & to share nature stories and photographs.
To contribute, email me at bloubird@gmail.com.

Wednesday, April 30, 2014

Goldfinches’ transformation into a yellow and black bird

In spring, American Goldfinch males transform from a dull olive green into brilliant sunny yellow birds. Their look is accented with dapper black caps and black wings and tails edged in white to attract the females. The more mature the adult male, the more extensive the bright white patches are on their tail feathers. The white on females and younger males is less extensive and drabber.

Female American Goldfinches are a duller olive green shade all year with hint of slightly more yellow after the spring molt. The young males in their second year get some of the yellow coat of feathers, but will not turn bright yellow until their second summer. But all of the goldfinches’ legs, feet and bill change from a dark grayish brown to a buffy yellow orange color even though their breeding season doesn’t begin until July.

What is so special is that most birds only go through one molt in the fall. The American Goldfinch is the only member of its family to complete two full molts a year. Marsh Wrens and Bobolinks are two other species of birds that have a two complete molts.

Molting is the process of replacing old feathers with new feathers. As the new feathers begin to grow, they push upward on the old feathers, causing the old feathers to loosen and eventually fall out. This feather replacement takes a great deal of energy.

The goldfinches’ requirement of a large amount of nutrients for their spring molt may be one reason they aren’t able to nest earlier in the season. Another reason they are late nesters is because the native thistle plant bears food sources as well as nesting material in the fall. After the male has serenaded the female with canary-like songs in late July or early August, goldfinches begin to nest for the first and only time of the year. Then they switch back to their drab winter coat.

Thank you Greg for sharing your brilliant photograph! If anyone would like to share a photograph of nature send it to bloubird@gmail.com

Related Articles:
- When Do the Goldfinches Return? http://bit.ly/ytfupb
- Why birds molt http://bit.ly/zvLuu3
- Feeding Goldfinch http://bit.ly/yptDDi
- Goldfinch Fun Facts http://bit.ly/yWunjT
- How to Attract More Goldfinches http://bit.ly/zgmwRk

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