Blue-headed Vireo
Vireo solitarius
The blue-headed vireo has similar plumage year round and does not drastically change its appearance during the breeding season. It can be characterized by its olive green upper body, two bold yellow wing bars down the edge of its wing, and a deep blue-grey crown from which it gets its name. The juvenile plumage of immature blue-headed vireos is not distinct but very similar to the adult plumage. Voice: The primary song of the blue-headed vireo is a simple, slow, monotonous tune that is often confused with the faster red-eyed vireo (Vireo olivaceus) song. The primary song is sung only by the males and usually only during the breeding season. The males become quite vocal during the breeding season, with the song frequency reaching its height prior to mating and then decreasing after copulation.
ID text from Wikipedia, CC BY-SA 4.0
White-eyed Vireo
Vireo griseus
Measurements: Length: 4.3–5.1 in (11–13 cm) Weight: 0.3–0.5 oz (10–14 g) Wingspan: 6.7 in (17 cm) Its head and back are a greyish olive, and the underparts are white with yellow flanks. The wings and tail are dark, and there are two white wing bars on each wing. The eyes have white irises, and are surrounded by yellow spectacles. Sexes are similar. Voice: The white-eyed vireo's song is highly variable, consisting of a rapid series of notes bookended by sharp 'chip' notes.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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