See all posts in the Birds of Carver County series
The American Goldfinch is a species with many other names associated with its feeding choices: Spinus tristis, which means sad thistle eater in Latin; catnip-bird; beet-bird; lettuce-bird; salad-bird; and wild canary.
If you stop on the road next to a weedy field in July or August, you may see a flock of small birds departing the area with an undulating flight. Later, within the leaves of trees in our neighborhoods or near our bird feeders, we will probably hear their musical notes announcing their presence and preparations for late-summer nesting when seeds of all types are plentiful.
Our feeders that are filled with sunflower seeds and nyjer thistle will usually guarantee their presence all year, probably in the company of others. They will also eat buds of fruit trees.
Tiny finches (5” long, 9” wingspan, weighing half an ounce) with appearances that change with the seasons and gender, American Goldfinches are common throughout most of Minnesota and many stay here all year. They molt their feathers twice each year — in the spring, males become bright yellow and black while hoping to be more attractive to females. The females add additional yellow to their overall olive-tan bodies. Their wings are black with white wing bars.
In October, a second molt will change over yellow feathers for tan uniforms and males will lose their distinctive black cap. Summer adults will have orange bills and legs, but this carotene-fueled color will fade to black and brown until the next spring.
In winter, American Goldfinches may travel in flocks with other seed-feeding birds that include Pine Siskins, Redpolls and other finches. During breeding season, pairs will form and territories will be loosely established.
At our feeders, there appears to be continual pushing and shoving until individuals fly up to fill nearby trees, scrape their conical bills free of crumbs, and return to nests to feed mates and nestlings. The species has an expandable esophagus that enables goldfinches to accumulate undigested food. This allows them to transport food to a nest or provide extra supply during adverse conditions. The species is one of the few that does not depend on insects, even when raising nestlings.
Nesting does not begin until late July or early August, when milkweed, thistle and other plants have produced their seeds, which goldfinches incorporate into their nests and feeding. The nest is built by the female, and the 12 to 14 days of incubation is by the female alone. Females are fed by regurgitation by their mate.
After hatching, the young take about two weeks to grow and then leave the nest. They will still depend on parental feeding for about three weeks. During this time, we can observe the fluttering wings and begging chirps of the fledglings switch on the feeding instincts of its parents.
Frequent cleaning of our feeders is essential to help prevent disease spread among the finches. Like House Finches, they are susceptible to mycoplasmal conjunctivitis, an eye condition that causes blindness and usually death.
Six different groups of goldfinch vocalizations have been identified: Song, Contact Call, Threat Call, Alarm Calls, Male and female Courtship Calls, and Begging Call by nestlings. Singing goldfinches are attracting mates, advertising their territory and warning against predators. But to our ears, they are providing the music of summer to those of us living in Carver County.
For more information:
- The Sibley Guide to Birds, David Allen Sibley
- Birds of Minnesota, Robert B. Janssen
- Breeding Birds of Minnesota, Pfannmuller, Niemi and Green
- The Audubon Society’s Encyclopedia of North American Birds, John K. Terres
- Birds of the World, Cornell Lab of Ornithology
- Online: All About Birds, Cornell Lab of Ornithology LINK
- Online: Minnesota Breeding Bird Atlas
