This handsome little finch, the state bird of New Jersey, Iowa, and Washington, is welcome and common at feeders, where it takes primarily sunflower and nyjer. Goldfinches often flock with Pine Siskins and Common Redpolls. Spring males are brilliant yellow and shiny black with a bit of white. Females and all winter birds are more dull but identifiable by their conical bill; pointed, notched tail; wingbars; and lack of streaking. During molts they look bizarrely patchy.
Goldfinches eat seeds almost exclusively. Main types include seeds from composite plants (in the family Asteraceae: sunflowers, thistle, asters, etc.), grasses, and trees such as alder, birch, western red cedar, and elm. At feeders prefers nyjer and sunflower.
Weedy fields, open floodplains, and other overgrown areas, particularly with sunflower, aster, and thistle plants for food and some shrubs and trees for nesting. Goldfinches are also common in suburbs, parks, and backyards.
Male and female move around together to choose a suitable nest site. The female builds the nest, usually in a shrub or sapling in a fairly open setting rather than in forest interior. The nest is often built high in a shrub, where two or three vertical branches join; usually shaded by clusters of leaves or needles from above, but often open and visible from below.
The nest is an open cup of rootlets and plant fibers lined with plant down, often woven so tightly that it can hold water. The female lashes the foundation to supporting branches using spider silk, and makes a downy lining often using the fluffy “pappus” material taken from the same types of seedheads that goldfinches so commonly feed on. It takes the female about 6 days to build the nest. The finished nest is about 3 inches across on the outside and 2-4.5 inches high.