Mangrove Warbler
Setophaga petechia
The mangrove warbler is around 13 cm (5.1 in) in length. Apart from the rufous hood of the male, all subspecies are very similar. Females and immature birds have similarly greenish-yellow uppersides and are a duller yellow below. Young males soon acquire breast and, where appropriate, head coloration. Females are somewhat duller, most notably on the head. In all, the remiges and rectrices are blackish olive with yellow edges, sometimes appearing as an indistinct wing-band on the former. The eyes and the short thin beak are dark, while the feet are lighter or darker olive-buff.
ID text from Wikipedia, CC BY-SA 4.0
Pine Warbler
Setophaga pinus
These birds have white bellies, two white wing bars, dark legs and thin, relatively long pointed bills; they have yellowish 'spectacles' around their eyes. Adult males have olive upperparts and bright yellow throats and breasts; females and immatures display upperparts which are olive-brown. Their throats and breasts are paler. The adult male pine warbler looks somewhat similar to the yellow-throated vireo which may cause some identification problems. The song of this bird is a musical trill. Their calls are slurred chips.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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