In the summer, The American Goldfinch is very rich in color. The male is a gorgeous bright yellow and the female is more of a muted olive color. However, in the winter, its difficult to tell the difference between the male and female because the male will molt into the olive color.
The Goldfinch is a highly social bird, often called “Wild Canary.” Its bright yellow plumage and roller-coaster- like appearance is amazing to watch.
Goldfinches will attach themselves to a plant unconcernedly, swaying as they continue plucking seed heads. At times, the plant will bend down and touch the earth with the Goldfinch completely oblivious. On breezy days, their acrobatic tendencies are to be applauded, and well worth stopping to watch.
In the spring the start of courtship behavior is signalled by one or more males chasing a single female. As well, he circles and performs two flight displays. One is a low flat flight. The other is an exaggerated version of his normal undulating flight in which he shows off by tucking his wings close to his body, plummets earthwards, and then spreads his wings to coast upward in a long series of loops. The female flies in an elusive zigzagging manner. During courtship, a pair will circle about, with the male warbling throughout the flight. Mating takes place in late summer, somewhere between late July and September, as does nest building.
The male marks his domain by warbling and flitting from perch to perch around the perimeter of the territory. The female builds the nest later in the summer up to 30 feet off the ground in the branches of a bush or tree. Nest building occurs in 10 to 40 minute spurts, during which material is brought to the site and laid down. There may be periods of hours or days when nothing is added.
The female strips fibers from dead trees, weeds, and vines and utilizes cattails as well as grass to construct the outer shell of the nest. She sometimes dismantles the nests of other birds to use the materials in her own nest. She reinforces the rim of the nest with bark bound by sticky spider silk and caterpillar webs. The nest is lined with plant down from thistles, milkweed, and cattails.
The male often accompanies the female on flights for nesting materials. He may carry some materials back, but leaves the actual construction of the nest to the female. He perches nearby, singing and calling to his mate. At hatching, the young are covered in fluffy grey down. Their eyes begin to open after three days. In the first week of life the nestlings are quiet, but by the second week they are active and noisily seek out the food brought at long intervals by their parents. The young birds grow rapidly; by the time they leave the nest 11-15 days after hatching they are covered with the beginning of the olive yellow juvenile plumage. Goldfinches are personally one of my favorite birds to watch with their agility and color, I find it to be truly capturing.