- For the greater part of the year, the American Goldfinch is primarily vegetarian. It eats seeds from many species of plants like thistle, ragwort, and sunflowers, as well as berries, tree buds, and sap. It will even eat garden vegetables, especially beet greens.
- As with other birds, insects become an important source of protein for the American goldfinch and its young during the breeding season.
- The childish voice of a goldfinch sounds a bit like a squeaky toy. Its call often includes a drawn-out mom-ma or bay-bee.
- Females build nests while males help collect materials and sing. Goldfinch nests are so tightly woven, that they can take on water unless the birds shelter their nests with their wings.
