Palm Warbler

The species comprises two distinct subspecies that may merit specific status.
"Yellow Palm Warbler" or "Eastern Palm Warbler" (S. p. hypochrysea) of the eastern third of the breeding range has brownish-olive upper parts and thoroughly yellow underparts with bold rufous breast and flank streaking. It migrates later in the fall than its western counterpart.
"Brown Palm Warbler" or "Western Palm Warbler" (S. p. palmarum) inhabits the remaining western two-thirds of the breeding range. It has much less yellow below, with less colorful streaking, and cold grayish-brown upper parts.