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
Blackburnian Warbler
Setophaga fusca
Blackburnian warblers are small passerines and average-sized wood-warblers. They measure around 11 to 13 cm (4.3 to 5.1 in) long, with a 20 to 22 cm (7.9 to 8.7 in) wingspan, and weigh 8 to 13 g (0.28 to 0.46 oz). The average mass of an adult bird is 9.7 g (0.34 oz), although is slightly higher in fall due to fat reserves, averaging 10.2–10.4 g (0.36–0.37 oz). Among standard measurements, the wing chord is 6.3 to 7.3 cm (2.5 to 2.9 in), the tail is 4.2 to 5 cm (1.7 to 2.0 in), the bill is 0.9 to 1 cm (0.35 to 0.39 in) and the tarsus is 1.6 to 1.8 cm (0.63 to 0.71 in).
ID text from Wikipedia, CC BY-SA 4.0
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