The American Goldfinch is a common bird found across most of the continental US and Canada. In breeding plumage, the bright yellow males can be spotted flying across open fields or eating from feeders, and they are easily discernible from the less vividly colored females. Their beautiful song (Haikubox recording here) and cheerful in-flight chirps (recording here) are often heard in concert with late summer insects.
Unlike most songbirds, this goldfinch breeds late in the summer when seeds are abundant. As strict vegetarians, goldfinch nestlings rely on their parents to supply a steady diet of seeds. Late breeding also ensures the availability of fluffy plant material for nests. You may see goldfinches all year, but after an early autumn molt, their autumn/ winter plumage is much more muted.
Keeping feeders filled with seeds is a great way to see more goldfinches, and so is hosting native plants that produce seed. We've seen them feasting on dandelion seed heads in our yard!