Black-throated Green Warbler
Setophaga virens
It has an olive-green crown, a yellow face with olive markings, a thin pointed bill, white wing bars, an olive-green back and pale underparts with black streaks on the flanks. Adult males have a black throat and upper breast; females and immature males have a pale throat and black markings on their breast. Measurements: Length: 4.3–4.7 in (11–12 cm) Weight: 0.3–0.4 oz (8.5–11.3 g) Wingspan: 6.7–7.9 in (17–20 cm)
ID text from Wikipedia, CC BY-SA 4.0
Northern Parula
Setophaga americana
The northern parula is one of the smaller North American migratory warblers, often being one of the smallest birds in a mixed feeding flock besides kinglets or gnatcatchers. Length is 10.8 to 12.4 cm (4.3 to 4.9 in), wingspan is 16 to 18 cm (6.3 to 7.1 in) and body weight is 5 to 11 g (0.18 to 0.39 oz). Among standard measurements, the wing chord is 5.1 to 6.5 cm (2.0 to 2.6 in), the tail is 3.7 to 4.5 cm (1.5 to 1.8 in), the bill is 0.8 to 1.1 cm (0.31 to 0.43 in) and the tarsus is 1.5 to 1.8 cm (0.59 to 0.71 in).
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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