The American Goldfinch, also called as the Eastern Goldfinch, is a small, migratory bird that thrives in North America. It is a member of the Finch family. Its breeding range spans from mid-Alberta to North Carolina during the breeding season, and from the southern edges of the Canadian border to Mexico during the winter.
As the only bird in its subfamily to experience a complete molt, the American Goldfinch exhibits sexual dimorphism in its coloration. As such, the male shows a lively yellow color in the summer and an olive color during the winter. The female, on the other hand, shows a dull yellow-brown shade, which only gets a little vibrant during the summer.
During the breeding season, the male exhibits a bright yellow plumage with a black forehead, wings, and tail. Each of his wings has one white wing-bar. Its tail also has a white marking.
The female, on the other hand, has yellowish-bray-brown upper parts, while its underparts range from bright yellow to dull yellow. Each of its wings has two light wing bars. It also has a light-colored bill. Its black tail is complemented with white-colored outer tips. During the non-breeding season, the female exhibits gray coloration in both its upperparts and underparts. Also, its wing bars become less distinct and its bill gets darker.
Both male and female juvenile American Finches have a dull brown back, and pale yellow underside. They have dull black shoulders and tail, that are complemented by buff-colored markings on wings and rump.
Distribution and Habitat
The preferred habitat locations of American Goldfinches are brushy and weedy areas at the edges of fields, rivers, and hedgerows, especially if the place is abundant with thistle and weeds. These would include suburban gardens, plantations, meadows, flood plains, and orchards.
They may also be observed in open deciduous and riparian woodlands, as well as areas of secondary growth. This habitat choice goes through as the spring and autumn migrations happen.
Their summer breeding range spans from North America’s east coast right across to the west coast. Saskatchewan forms the northern boundary of their range, which then stretches south towards North Carolina on the east coast, and northern California on the west coast. Their winter range includes southern Canada, and runs through the United States to some parts of Mexico.
As granivores, American Goldfinches primarily feed on little seeds, particularly thistle. The feeding process is facilitated by their conical beak, which aids in removing the seeds; and agile feet, which is used in gripping the seedbeds’ stems while feeding.
During summer, insects, particularly aphids, dominate their diet. And they feed their young with regurgitated seeds.
They would often visit seed feeders, especially those in the East. They would actively flock in groups to eat thistle and sunflowers on the roadsides and brushy fields.
With their sociable nature, they would usually assemble in groups, especially when it is not breeding season. They are observed in large groups while feeding and migrating. They are often observed flocking with redpolls and Pine Siskins.
They are also known as active foragers, climbing nimbly from one tree to another and hanging from seed-heads and other objects.
These birds create distinct calls when flying. Indeed, they are famous for being songbirds. The song that they create is a series of musical warbles and twitters.
American Goldfinches do not show a fierce territorial behavior. Indeed, its alarms are primarily used for defense against predators. Some of their known predators are snakes, weasels, squirrels, and blue jays.
However, they only exhibit a short-lived territoriality during the building of nests. Their preferred nest locations are loose colonies, in the upright fork of a shrub, tree, or sometimes, a dense weed. The nest is commonly made of plant fibbers and spider webs that were woven into a compact cup, and lined with thistle down.
In average, female American Goldfinches incubate about 4 to 6 eggs. The incubation period for these eggs would run between 12 to 14 days. Interestingly, the male brings food for the female as the incubation period goes on. This extends up to the first few days after the hatchings of the eggs. Eventually, both the male and the female would bring food for the young.
Since they are monogamous animals, they only produce one to two brood each year. The young fledge the nest after 12 to 17 days. However the feeding process still continues for a few weeks.
Their breeding season is associated to the availability of food, beginning in late July.
American Goldfinch birds have a stable population throughout their breeding range. According to the North American Breeding Bird Survey, their population has remained stable in the past 40 years. Their estimated global breeding population is 42 million. They have a 6 out of 20 rate on the Continental Concern Score, and are not included on the 2012 Watch List.
Human activities have contributed to the stability of the population of American Goldfinches. The birds are attracted to bird feeders in residential areas, which has helped in their survival rates in places with increased human habitation. Also, activities such as deforestation paved way for the creation of open meadow habitats for the birds.