Black-throated Blue Warbler
Setophaga caerulescens
The black-throated blue warbler measures 13 cm (5.1 in) in length and weighs 8.4–12.4 g (0.30–0.44 oz). Wingspan ranges from 7.5–7.9 in (19–20 cm). This is a strongly sexually dimorphic bird. The adult male has white underparts with a black throat, face and flanks. The upperparts are deep blue. The immature male is similar, but with greener upperparts. The female has olive-brown upperparts and light yellow underparts with darker wings and tail, gray crown and brown patches on the cheek. Both sexes have a thin pointed bill and small white wing patches which are not always visible.
ID text from Wikipedia, CC BY-SA 4.0
Yellow-throated Warbler
Setophaga dominica
The yellow-throated warbler is 13–14 cm (5.1–5.5 in) long, with a wingspan of 21 cm (8.3 in), and weighs 8.5–11.3 g (0.30–0.40 oz). In summer, male yellow-throated warblers display gray upperparts and wings, with double white wing bars. Their throats are yellow, and the remainder of their underparts are white, and are streaked with black on the flanks. Their heads are strongly patterned in black and white, with a long supercilium. The remiges and rectrices are black.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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