If you enjoy watching birds at a backyard feeder, you are no doubt familiar with the American goldfinch (Carduelis tristis). The males have put on their bright yellow coats and are impressive when gathered in large numbers around the feeder.
The goldfinch is a common bird in our area, hanging around all year. They frequent weedy fields, vacant lots, and areas with scattered trees. It is a small bird around 4-5 inches long with a wingspan of 8 inches. Their winter color is a dull yellow to olive, and the females stay this way all year. But the males turn a bright yellow in the spring with a black head cap and black wings with white wingbars. He definitely dresses up for breeding season. They do this with a complete molt in the spring, and the goldfinch is the only member of its family to have a second molt; all the other species have just one molt each year in the fall.
Speaking of breeding season, the goldfinch takes care of business later than most nesting birds. It usually does not start until late June or early July when everyone else is usually done. The late timing is probably due to the availability of suitable nesting materials and seeds for feeding young. The bird is normally monogamous and produces only one brood of young each year. But some females switch mates after producing the first brood of young and will produce a second brood while the first male cares for the fledglings. Females build woven cup nests in weedy areas, briar patches, or shrubs. 4-6 whitish to pale blue eggs are laid and incubated by the female, who is fed by the male during this time. Incubation takes 12-14 days, and when hatched the young are fed regurgitated seeds until they leave the nest after only 10 to 16 days.
Goldfinches primarily feed on small weed seeds and are particularly fond of thistle seed. They also feed on the seed of ragweed, sweetgum, sunflower, dandelion, and goldenrod. They also eat small quantities of aphids and caterpillars. The birds are gregarious and almost always found in flocks, though these groups are smaller during breeding season.
Goldfinches are easy to attract to your yard. Simply provide thistle and black oil sunflower seed, and they will come. You can make your landscape attractive for them by planting late summer and fall wildflowers.
Information for this article and a great web site for birds is: All About Birds: