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Birdaday Field Notes

Species profile

American Goldfinch: identification, molt calendar, food and nesting

The American Goldfinch is the small yellow-and-black finch at the nyjer feeder, and the one that seems to vanish each fall. It stays, molting into drab brown. Cornell notes it is the only goldfinch that replaces its body feathers twice a year. A shorter profile sits on common backyard birds.

Quick facts

Fact American Goldfinch
Scientific name Spinus tristis, family Fringillidae (Cornell). Named Fringilla tristis by Linnaeus in 1758 (Wikipedia)
Length 4.3–5.1 in (Cornell); 4–5 in (Audubon)
Weight 0.4–0.7 oz (Cornell, Audubon)
Wingspan 7.5–8.7 in (Cornell); 8–9 in (Audubon)
Population About 44 million (Partners in Flight, via Cornell; Audubon). Down about 0.6% a year, 27% in total, 1966–2019 (Cornell)
Status Low Concern (Cornell); Least Concern (IUCN, via Audubon)
Oldest known 10 years 9 months, recaptured in Maryland (Cornell). Wikipedia gives 10 years 5 months
State bird of New Jersey, Iowa and Washington (Cornell)

How to identify an American Goldfinch

Cornell describes a small finch, smaller than a Tufted Titmouse, that flies in a bouncy, undulating pattern and often calls in flight.

Male American Goldfinch perched on a broken branch tip: bright yellow body and back, black forehead, orange bill, black wings with white bars and edging, white under the tail American Goldfinch in winter plumage on a dark metal pole, seen from behind: unstreaked olive-brown back, yellowish face and throat, black wings with bold white wingbars
Two male American Goldfinches, as identified by the photographers. Left: spring, with the black forehead and black wings with white markings of breeding plumage. Right: winter plumage, unstreaked brown with blackish wings and pale wingbars (Cornell).
Photos: Mark Olsen (left) and Joshua J. Cotten (right) on Unsplash
American Goldfinch field marksA simplified side view of a generic breeding male goldfinch perched on a twig, facing left, with seven numbered field marks: black forehead, short conical bill, bright yellow body, black wings with white markings, white under the tail, short notched tail, and no streaks. To the right, three color swatches compare a breeding male, a breeding female and a winter bird. 1 2 3 4 5 6 7 8 9 10
  1. Black forehead on breeding males (Cornell).
  2. Short conical bill: pink most of the year, bright orange after the spring molt in both sexes (Wikipedia).
  3. Bright yellow body on males in spring and early summer (Cornell).
  4. Black wings with white markings; in winter, two pale wingbars (Cornell).
  5. White patches above and below the tail (Cornell).
  6. Short, notched tail (Cornell).
  7. No streaking, a key clue for females and winter birds (Cornell).
  8. Breeding male: yellow with black forehead, wings and tail (Cornell, Audubon).
  9. Breeding female: duller yellow below, olive above (Cornell).
  10. Winter bird: drab, unstreaked brown with blackish wings and two pale wingbars (Cornell).
Drawn for Birdaday Field Notes as a generic finch shape, not copied from any field-guide plate. Field marks follow the Cornell Lab's All About Birds ID page, Audubon and Wikipedia, cited below. Colors approximate. Not to scale.

Look-alikes

Cornell also lists the male Evening Grosbeak as similar. The three closest look-alikes, from Cornell's ID pages:

Species Where How it differs (Cornell)
Lesser Goldfinch Western US, south to the Peruvian Andes Smaller (3.5–4.3 in). Males have a glossy black cap and a black or dull green back. Females show a white patch on the wing edge
Lawrence's Goldfinch Mainly California and the Desert Southwest; nomadic Breeding male mostly gray, with yellow on breast and wings and a black chin and forecrown
Pine Siskin Evergreen and mixed forests; winter feeders Brown and heavily streaked, with a slimmer, pointed bill and subtle yellow wing edging

Song and calls

The molt calendar: why goldfinches turn brown

Goldfinches molt twice a year (Cornell). In the late-summer molt they replace all their feathers; the spring molt replaces body feathers only, so wing and tail feathers last a full year (Middleton 1977; Wikipedia). New feathers grow in one at a time, so molting birds look patchy; they aren't sick (Cornell).

Timing below comes from A. L. A. Middleton's study of 3,633 goldfinches at Guelph, Ontario (1967–1975), in The Condor (1977):

American Goldfinch molt and nesting calendar, January to DecemberA twelve-month chart with five rows: adult spring body molt from late January, heavy from mid-March through May, tapering by early July; first mostly yellow males in the second week of April; nesting from late June through August, peaking late July to early August; adult fall molt from early to mid-August through early November, with body pin feathers into December; and first-year birds' first molt from September, peaking in October and November, with pin feathers into January. Dark bars mean heavy activity and pale bars light activity. JFMAMJJASOND 1 2 3 4 5
  1. Spring body molt, adults: first head and throat pin feathers in late January; heavy from late March through May; tapering off by early July.
  2. First mostly yellow males: second week of April, while still molting heavily.
  3. Nesting: from late June, peaking late July to early August (NestWatch); most nesting in July and August (Audubon).
  4. Fall molt, adults: from about mid-August (some males early August, late-nesting females mid-September); flight feathers done by late October to early November; body pin feathers into December, sometimes January. Males start about a week before females.
  5. First-year birds: body molt from September, peaking in October and November; head pin feathers into January.
Drawn for Birdaday Field Notes. Rows 1, 2, 4 and 5 follow Middleton (1977), a study of one population at Guelph, Ontario; row 3 follows NestWatch and Audubon. Dark bars mark heavy activity, pale bars light activity; month positions are approximate.

Middleton found that body molt barely overlaps breeding, and suggested the long spring molt may help explain why goldfinches nest so late.

Food and feeders

Cornell says goldfinches eat almost only seeds and swallow insects only by accident. Natural foods are composite plants such as sunflower, thistle and aster, plus grasses and trees like alder, birch and elm.

At your feeder What the sources say
Nyjer ("thistle") A favorite (Cornell). Not related to North American thistles; use a feeder with very small ports and feed it alone (FeederWatch)
Black-oil sunflower A favorite (Cornell). The most common feeder seed in North America (FeederWatch)
Sunflower hearts and chips Keep dry; they spoil faster than seed in the shell (FeederWatch). Not in tube feeders where moisture collects; offer only what birds eat in a day or two (Cornell seed guide)
Native plants Native thistles, other composites and native milkweed (Cornell)

Goldfinches use hopper, platform and hanging feeders, even swaying ones (Cornell). Cornell says to rake the ground under feeders to reduce the spread of disease. See how to clean a bird feeder, bird feeder types and what to feed backyard birds.

Winter. Migration is irregular; more birds stay north when food is good (Audubon). Goldfinches are most abundant at feeders in winter (Cornell).

Nesting: the late starter

Goldfinches wait for weeds to go to seed, then use thistle and milkweed down for nests and seeds for their young (Cornell). The female builds, in about 6 days (Cornell). The nest is an open cup in a shrub, not a cavity, so goldfinches aren't on our birdhouse dimensions table. Sources differ:

Stage Cornell Lab Audubon NestWatch
Start Waits until June or July Most nesting in July and August From late June; peak late July to early August
Site Shrub or sapling in the open, often where 2–3 vertical branches meet Usually a deciduous shrub or tree, under 30 ft Shrub or small tree, just above ground to several meters up
Nest Cup of rootlets and plant fibers, lined with down; about 3 in across, 2–4.5 in high Compact cup of plant fibers, spiderweb and down About 3 in across, 3–4 in high
Clutch 2–7 eggs 4–6, sometimes 2–7 2–7
Incubation 12–14 days About 12–14 days, female only; male feeds her About 2 weeks
Nestling period 11–17 days Young leave 11–17 days after hatching About 12 days
Broods 1–2 Not stated Not stated

All three agree the cup is woven tightly enough to hold water. Brown-headed Cowbirds sometimes lay in goldfinch nests, but the cowbird chick seldom survives past about three days on the all-seed diet (Cornell); a 1977 study found cowbird eggs in 9% of nests (Wikipedia).

For your Bird-a-Day streak

Goldfinches breed coast to coast and winter from southern Canada to parts of Mexico (Wikipedia), so where those ranges overlap they can be found all year. Birds heard count (see the challenge guide), and the flight call is given often in flight (Cornell). Plan reserve birds like this, the Blue Jay and American Robin with the species planner.

Goldfinch-friendly yard checklist

Sources