Unlike many birds, goldfinches molt their body feathers twice a year. They have bright, attractive yellow feathers in the spring before breeding and much denser olive brown feathers after nesting in the fall. The color of the legs, feet and bill of the American Goldfinch change with each feather molt too. In winter plumage, their legs, feet and bill are dark grayish brown. In breeding plumage they change to a buffy yellow orange color.
American Goldfinches are partial migrants, meaning only part of the population migrates annually and if it is a rough winter they can become nomadic. Their winter range includes southern Canada and stretches south through the United States to parts of Mexico. During heavy snowstorms they may move further south to find food only to move back when the weather clears.
American Goldfinches are common feeder visitors and prefer Nyjer® (thistle) and sunflower seeds. I have dozens of goldfinches right now attacking my window feeder full of No-Mess Blend, a seed blend full of sunflower seeds without the shell.
They also appreciate the heated bird bath. The goldfinches drink frequently and will stay close to reliable sources of water because of their almost exclusive diet of seeds.