Length: 3.9-4.7 in (10-12 cm)

This bright yellow warbler with a black cap is one of the smallest warblers in the U.S.  Females are similar in color but show variations in the amount of black on the top of the head, from a few blackish feathers to a small dark cap. They rarely slow down, dashing between shrubs, grabbing insects from one leaf after another, and popping up on low perches to sing