The Yellow Warbler is a small songbird of the warbler family. Both sexes are yellow in color, with light olive upperparts. Males sport rusty chest stripes during breeding season. The males of some subspecies also develop rusty more... caps during breeding as well. Yellow Warblers breed across much of the United States. They winter from Central America down into northern South American countries. The build their cup nests in trees and prefer open woodland habitat for breeding.