Monday, September 28, 2009

In the backyard... American Goldfinch

American GoldfinchAmerican Goldfinch, Forest Grove, Oregon on 11 April 2009 by Greg Gillson.

 

"Wild canary." That's what many people call the American Goldfinch. And no wonder. Both birds are bright yellow finches with a sweet lilting song.

American Goldfinches are found at lower elevations throughout the Pacific Northwest. They avoid high mountains, dense forests, and extensive sage flats, however. They move right in after clear cuts and are common for several years until trees start replacing the weedy plants.

The scientific name of the goldfinch genus is Carduelis from the Latin word for thistle. Indeed, thistle seed is a favorite food of goldfinches. Thus, you will usually find American Goldfinches in weedy fields.

Throughout most of the year you will find these finches in large flocks. They pair up and nest late, many as late as July or August. These birds are primarily residents in the Pacific NW, but their nomadic nature in winter can make their flocks harder to find.

Breeding males (as in the photo above) are bright yellow with a black crown, black wings with white wingbars, black tail with white inner edges, and a white rump and undertail coverts. Females are duller, brightest yellow on the underparts, but greenish-olive on the upperparts, lacking the black crown.

In winter the young birds and adults are rather plain brownish or olive with darker wings with buffy wingbars (immatures) or yellow upper and white lower wingbar (adult males). The males lack the black crown in winter.

Lesser Goldfinches are similar. Lessers have yellow breasts and undertail coverts and green backs and rump throughout the year. Lesser Goldfinches are found in the Willamette Valley of western Oregon (and extreme southern Washington), sparsely eastward through southern Idaho, and south.

In the Central Valley of California is found the quite gray Lawrence's Goldfinch with its yellow wingbars that are not too similar to American Goldfinches.

The small brown-streaked Pine Siskin is related to goldfinches, but shows just a touch of yellow wing stripe and tail corners and are not likely to be mistaken for goldfinches.

To attract American Goldfinches to your backyard, buy a thistle sock and fill with Niger seeds (trademarked as "Nyjer"). Also provide plenty of water for drinking and bathing in summer.