As we head toward spring, many of the birds visiting our New England backyard feeders may begin to change in appearance. Spring is mating season and that means male birds will begin “dressing to impress.” One of the best examples of birds coloring up in the spring is the American Goldfinch.
Although goldfinches do migrate south for the winter, thistle feeders in the northern United States will have goldfinches all year round, as we reside in both the summer and winter range of these birds. We will, however, notice a profound difference in their coloration between winter and summer months.
In the winter, they still have the same black and white markings, but the predominant body color of both male and female goldfinches is a drab olive-yellow. Over the next few weeks, however, we’ll see that color change to the bright yellow in the males that gives the goldfinch its name. The males will also develop a pronounced black cap that extends from the top of the beak and back over the bird’s crown.
Female goldfinches will also become brighter in the spring and summer months, but will never achieve the bright yellow coloration of the males. Juvenile males will not achieve their color until their second year.
American goldfinches molt in the spring to get rid of their drab winter feathers before they grow their summer plumage. In the fall, the process repeats with bright summer feathers giving way to the olive drab for winter. A. L. A. Middleton, in “Molt of the American Goldfinch,” tells us that the peak of the spring molt occurs in April, although individuals may be found molting from mid-January to early July. The fall molt, says Middleton, peaks between September and November.
Here in the east, goldfinches breed in July, later than many of the other common summer birds. Goldfinch nests are typically built 10-20 feet off the ground in the branches of trees or brush. Erika Tallman of Northern State University writes that goldfinch nests are built so tightly from the silks of thistles, milkweed and cattails that they can fill up with water if the parents don’t cover them with their bodies. Goldfinch eggs are whitish with a blue tint.
Those with backyard feeders know that goldfinches prefer nyjer thistle seed and they will often swarm over the thistle seed feeder. Remember, though, that black bears will also take thistle feeders during the summer and autumn months, so either take in your feeders when bears are active or hang them out of reach from overhead lines. Goldfinches also eat other small seeds from trees and flowers. According to Tallman, goldfinches will eat insects when nesting, but generally not at other times of the year and still only as a small part of their diet.
Goldfinches, with their bright summer colors and plentiful numbers are welcome and sought after backyard visitors throughout New England.