Friday, March 27, 2015

American Goldfinches Changing Right Before Our Eyes

I've gotten a little rush of bird identification questions lately, and most have pertained to one particular species. Every spring the American goldfinches transform from their winter plumage to their breeding plumage right before our eyes. While the adult males in the breeding season are pretty unmistakable, the winter plumage and transition plumages sometimes confuse feeder observers.

Below is a series of photos showing the gradual plumage changes:

 In the winter, the American goldfinches look like the bird on the right side of the feeder. The bird on the left is a pine siskin. The two species often occur together. Many casual backyard feeder watchers are unaware of the plumage changes the goldfinches go through during the year. In the winter they are brownish-gray with perhaps a hint of dull olive. The wings are black with white stripes.
American Goldfinch (right) by Taylor Piephoff

By this time of year, the males are starting to acquire the bright yellow plumage that most people are accustomed to seeing. Note the patchy yellow coming in among the patches of gray winter plumage, and the aquisition of the black cap.
American Goldfinch Male by Bruce Naliboff

The females show this transition too. This bird is starting to show the yellow coming in, but it is not as bright, since this is a duller female bird.

Female American Goldfinch by Peg Bania

In a few weeks the transformation is complete. The adult males have assumed their strikingly brilliant summer suits.
Adult Male American Goldfinch by John Ennis

You may continue seeing the goldfinches at your feeders throughout the summer. Here is a mix of adult males and adult females. The females will be a yellow-green when nesting but will be more gray in the winter. Both males and females have the black wings with prominent bars or stripes throughout the year.
Male and Female American Goldfinches by Cathy Miller