Quiz time: How many birds on our Goose Pond Bird List begin with their common name “American”? Answer at the end.
Every September, we look forward to seeing flocks of American goldfinches at Goose Pond Sanctuary. This year is no exception. We noticed the first flocks the first week of September.
Goldfinches nest throughout Wisconsin and are found in the southern two-thirds of Wisconsin year around. Partners in Flight estimates a global breeding population of 42 million, with 91% spending some part of the year in the U.S., 33% in Canada, and 6% wintering in Mexico. The North American Breeding Bird Survey found a small decline between 1966 and 2014 in their numbers.
American goldfinches are the latest nesting species nest in Wisconsin. Goldfinch nests with eggs have been found from June 26 to August 30, while young have been found in nests from July 1 to September 25. They nest after the peak of nesting of brown-headed cowbirds and so their nests are rarely parasitized by cowbirds.
They like to nest in a variety of habitats from rural to urban areas, especially where there are low shrubs to place their nest. According to researchers the nest is an open cup of rootlets and plant fibers lined with plant down, often woven so tightly that it can hold water. The female lashes the foundation to supporting branches using spider silk, and makes a downy lining often using the fluffy “pappus” material taken from the same types of seed heads that goldfinches so commonly feed on. It takes the female about 6 days to build the nest. The female usually has a clutch of 2-7 eggs, an incubation period of 14 days, and 17 days to fledging.
In September, we found a nest at Goose Pond with two eggs which appeared to be a nest that fledged young but two eggs did not hatch.
Goldfinches are active, acrobatic finches that balance on the seed heads of thistles, dandelions, and other plants to pluck seeds. They have a bouncy flight during which they frequently make their “po-ta-to-chip" calls. By being late nesters, they can take advantage of many plant species with tasty seeds that are ripe for the flocks of goldfinches.
In September, flocks of goldfinches are first seen feeding on saw-tooth sunflower that has small seeds. After they have cleaned up the sunflowers they concentrate feeding efforts on prairie dock that has a larger “sunflower” seed. We collect prairie dock seed in large quantities for our restorations and it have to collect prairie dock just before the seeds are fully ripe to avoid losing them all to goldfinches. (Don’t worry, we leave plenty for the birds!)
After all the prairie dock seed has been eaten, collected, or fallen on the ground, goldfinches head for our food plot and spend the winter feeding on black oil sunflower seeds.
Written by Mark and Susan Foote-Martin, Goose Pond Sanctuary resident managers
Quiz Answer: 13 species. American wigeon, American coot, American avocet, American golden-plover, American woodcock, American bittern, American kestrel, American crow, American robin, American pipit, American goldfinch, American redstart, and American tree sparrow
Cover photo by Eric Begin