American goldfinch

Name and taxonomy

Carl Linnaeus described the American goldfinch in 1758 and placed it in the genus Fringilla. Later work moved it to Spinus, the genus of the New World goldfinches and siskins. In 1976 that genus was folded into Carduelis as a subgenus. Newer studies have brought Spinus back as a genus of its own. Carduelis comes from carduus, the Latin word for a thistle. Its species name, tristis, means sorrowful in Latin.

The bird shares an English name with the European goldfinch, but the two are not close kin. They belong to separate genera on separate continents. Four subspecies of the American bird are recognised. The eastern goldfinch is the commonest, and the pale goldfinch is bigger and lighter. The northwestern goldfinch is smaller and darker, on the seaward side of the Cascades. The willow goldfinch of California and Baja keeps browner winter feathers.

Evolution and relatives

The nearest relatives are the lesser goldfinch and Lawrence's goldfinch. The siskins sit close to them in the same group. Like other small finches, they carry conical bills built for prising seeds out of a head. The family Fringillidae holds most of the world's true finches. The American goldfinch belongs to the cardueline branch of it.

One habit sets the species apart from every other cardueline finch. It moults its body feathers twice a year rather than once. That second moult probably buys the male a bright breeding coat and a dull winter one. The four subspecies differ only in size and in the shade of the plumage. Their ranges overlap on the Pacific slope, which probably keeps them from drifting apart.

Appearance

This is a small, neat finch, 11 to 14 centimetres long. The wingspan runs 19 to 22 cm, and the weight runs 11 to 20 grams. The tail is short and notched, at 4.2 to 5.1 cm. The wing chord measures 6.5 to 7.8 centimetres. The bill is small and cone-shaped, pink for most of the year. It turns bright orange in both sexes at the spring moult.

After that moult the male is a brilliant lemon yellow. Carotenoid pigments from his food make the colour, so his diet shows in his feathers. He carries a jet black cap and a white rump that flashes in flight. The female is mostly brown, paler beneath, with a yellow bib. The wings and tail keep their colour through both moults, black on him and brown on her.

The autumn moult replaces all of that with buff underparts and olive-brown upperparts. Winter birds keep only a pale yellow face and bib. The sexes look almost alike then, though the male keeps yellow shoulder patches. A young bird has a dull brown back and pale yellow underparts. Its wing and rump markings are buff rather than white.

Habitat and range

The goldfinch wants open ground where weeds can grow. Fields, meadows, flood plains, roadsides, orchards and gardens all suit it. It also uses open deciduous woodland, riverside trees and scrubby regrowth. The breeding range crosses the continent from coast to coast. It reaches north to Saskatchewan and south to North Carolina and northern California.

The species is a short-distance migrant that moves when cold and hunger push it. Movement seems to begin as nightly low temperatures approach freezing. Flocks travel in tight groups with a wavelike flight. The winter range runs from southern Canada down into parts of Mexico. Northern birds may stay put where feeders keep them fed. GBIF holds records from 16 countries, and iNaturalist carries 197,134 observations.

People tried to plant the bird outside its range twice. One attempt reached Bermuda in the nineteenth century. Another reached Tahiti in 1938. Neither population took hold.

Diet and feeding

The American goldfinch feeds by day and eats seeds almost to the exclusion of all else. The Cornell Lab of Ornithology calls it one of the strictest vegetarians among birds. Thistle, teasel, dandelion, ragweed, mullein, goatsbeard, sunflower and alder all feed it. It also takes tree buds, maple sap and berries. Insects appear only now and then, and mostly go to the chicks for protein. At a garden feeder it prefers niger seed, which people often call thistle seed.

The conical bill prises seeds straight out of a seed head. The feet do as much work as the bill, which is unusual in a finch. A bird will hang upside down from a seed head to reach the middle of it. In spring it pulls a birch or alder catkin up with the bill. It then pins the catkin against the branch with a foot and works it over. That trick opens food that other small birds cannot reach.

Behaviour and social life

The flight is a series of arcs, and the bird beats its wings, then folds them and glides. It calls during the flapping part and falls silent while it coasts. Outside the breeding season the goldfinch is highly social. Large flocks form, often mixed with other finches. In the breeding season two or three pairs may settle in a loose colony.

A flock has a pecking order that shifts with the calendar. Males win most contests outside the breeding season. Females come out on top once breeding starts. A study published in 1987 found that a hungry subordinate could win a place at a feeder. Males chase other males away while a nest is going up, and females chase other females. That aggression stops once the eggs are laid.

Goldfinches settle arguments with posture before they use their bills. In the head-up display the neck and legs stretch a little, which signals mild threat. In the carpals-raised display the neck pulls back and the wing joints lift. A bird in that pose is likely to attack. A loser leans away, flexes its legs and turns its bill down.

Communication and senses

The song is a run of musical warbles and twitters, often ending on a long note. The flight call is written as tsee-tsi-tsi-tsit or as per-chic-o-ree. Some listeners hear the same call as the words potato chip. A sitting female calls her mate in with a soft, steady tee-tee-tee-tee. Nestlings start a chick-kee or chick-wee call shortly before they fly.

Adults use two alarm calls at the nest. The sweet call brings other goldfinches in and pulls a predator's attention about. The bearbee call tells the nestlings to go quiet and crouch down. Colour probably carries as much as sound in the breeding season. A male's bill colour and plumage advertise both his health and his genes.

Reproduction and life cycle

No other native North American bird waits as long to breed, except sometimes the sedge wren. Courtship begins in late July, when the seed crop peaks. A male chases a female while she flies in tight zigzags. If she accepts him, the pair circles in wide loops while he warbles. He then marks a territory by singing from perch to perch around its edge. He finishes with a flat low flight and then a looping dive and climb.

The female builds the nest alone in a shrub or tree, up to 10 metres above the ground. Building takes about six days, in bursts of 10 to 40 minutes. The male follows her while she gathers material but leaves the work to her. Bark, weeds, vines and grass make the outer shell, and the cup is about 6.5 centimetres across. Spider web and caterpillar silk bind the rim, and plant down lines the inside. The weave is so tight that rain can fill it and drown the young.

A clutch holds four to six pale bluish-white eggs, each about 16 by 12 millimetres. The female incubates alone for 12 to 14 days while the male feeds her. Chicks hatch naked and blind, and their eyes open after three days. The mother feeds them regurgitated seed with a few insects mixed in. They grow juvenile plumage in 11 to 15 days and start short flights. The male feeds the fledglings for up to three weeks and finds them by their calls.

Most pairs raise a single brood in a year. Brown-headed cowbirds lay in about 9% of goldfinch nests. Almost no cowbird chick survives in one, because it cannot live on a diet of seed. The goldfinch has no known behaviour against brood parasites, so the seed diet appears to do the work. Birds breed in their first year, and the oldest known wild bird reached 10 years and 5 months.

Predators and threats

Snakes, weasels, squirrels and blue jays raid nests for eggs and young. Hawks and cats take fledglings and adults as well. A goldfinch does not mob a predator inside its territory. It answers with alarm calls and nothing more. The sweet call gathers neighbours, which may confuse the hunter.

Heavy rain can drown nestlings when the parents leave the cup uncovered. Cowbird eggs probably cost a pair some effort, even though the chicks fail. The population is thought to be falling slowly across the range. Audubon names a warming climate as a pressure on the range. Cats around houses probably kill more goldfinches than any wild predator does.

Population and conservation

The IUCN evaluated the species as Least Concern in 2025. The global range covers about 7,900,000 square kilometres. Between 42 and 47 million mature birds live in it. That total is expected to fall, though slowly. Nothing in human activity threatens the species as a whole.

Clearing woodland has helped this bird, unlike most. Open ground grows the weeds whose seeds the goldfinch lives on. Long-distance migrants lose out when forest goes, while short-distance ones gain. Garden feeders raise winter survival where people keep them filled. The bird appears to be a familiar sight in suburbs across its range.

Relationship with humans

Backyard birders draw goldfinches with niger seed in a hanging feeder. Planting zinnias, cosmos, bee balm or globe thistle works as well. Those plants set the seed heads the finches prefer. The species is common in residential streets throughout its range. It probably does no damage to crops or property.

Three states have named the American goldfinch as their official bird. Iowa adopted it in 1933 and New Jersey followed in 1935. Both states use the name eastern goldfinch. Washington chose the willow goldfinch in 1951, on a vote by schoolchildren. Few birds appear to have been picked as a state emblem by children.

In culture and myth

The American goldfinch appears to carry little old folklore of its own. Its cultural weight seems modern and civic instead. Three state legislatures put the bird on their list of official symbols. A generation of Washington schoolchildren chose their own state bird in 1951. The bird appears on state road signs, coins and school posters.

The older goldfinch stories in Europe belong to a different bird. That bird eats thistle seed, and Christian painters linked it to the crown of thorns. Raphael put one in the hands of John the Baptist in a painting of about 1505. Painters also used the goldfinch as a sign of endurance and of new life. None of that lore appears to attach to the American bird, which is only a namesake.

The two birds seem to share one thing, which is the thistle. The old genus name Carduelis takes its root from the Latin word for that plant. Trappers in nineteenth-century Britain caged thousands of European goldfinches a year. Public anger at that trade fed the founding of a large British bird charity. The American bird appears to have escaped that trade and stayed a wild garden visitor.