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
Chestnut-sided Warbler
Setophaga pensylvanica
This species is a moderately-sized New World warbler. Despite having very different plumage, it is thought to be closely related to the widespread yellow warbler. In total, this species measures from 10 to 14 cm (3.9 to 5.5 in) in length and spans 16 to 21 cm (6.3 to 8.3 in) across the wings. Body weight ranges from 8 to 13.1 g (0.28 to 0.46 oz). Among standard measurements, the wing chord is 5.7 to 6.8 cm (2.2 to 2.7 in), the tail is 4.2 to 5.8 cm (1.7 to 2.3 in), the bill is 0.9 to 1 cm (0.35 to 0.39 in) and the tarsus is 1.7 to 1.9 cm (0.67 to 0.75 in). Voice: The songs are high whistled lines often described as pleased, pleased, pleased to MEECHA. This accented song is used primarily to attract a female and decrease in frequency once nesting is well under way. Males also sing unaccented songs (without the MEECHA at the end) and these are used mostly in territory defense and aggressive encounters with other males.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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