The males has the bright-yellow background color, the black with yellowish spots wings and tail. The female most often has the yellowish-green upper parts, greenish-grey wings, and the yellowish-white with longitudinal strikes under parts. The females' coloring is very variable; some females look brightly as males. Juveniles are similar on females but have darker under parts. First year males also are similar on females but more yellow on the breast and abdomen, more contrast on tail.