Question: what are small yellow birds?
Answer: Habitat. American Goldfinches can generally be found in brushy and weedy habitats at the edges of fields, rivers, and hedgerows, especially when thistle is present. ... 
Behavior. Flocks are common outside of the breeding season, and American Goldfinches often flock with redpolls and Pine Siskins. ... 
Diet. ... 
Nesting.