The American goldfinch (Carduelis tristis) or wild canary is the abundant yellow bird in much of the United States and southern Canada, often seen in meadows and back yard bird feeders.
The American goldfinch is a small bird, smaller than a sparrow at 4.5 to 5 inches in length, with a wingspan of 8.75 to 9 inches. Males have bright yellow plumage during the breeding season, with a black forehead, black wings and tail; both wings and tail bear white edge marking. The winter plumage in the male is duller in coloration, as is the female plumage; in addition, the female does not bear a black forehead.
The bill is short, conical, and usually pink in color; it turns orange during the spring molt. The American goldfinch molts during spring and fall, the only member of its family to do so.
The striking yellow plumage is produced by carotenoid pigments such as leutin, zeoxanthin, and beta-carotene; the black plumage comes from the pigment eumelanin. All are derived from the bird’s diet of seeds.