Cassin's Vireo
Vireo cassinii
The vireo is 11–14 cm (4–6 inches) long. It has a grayish olive head, back, and flanks, with whitish underparts. One of its distinctive features is the solid white "spectacles" around its eyes, along with white wing bars. These markings set it apart from other similar species like the plumbeous vireo and the blue-headed vireo.
ID text from Wikipedia, CC BY-SA 4.0
Plumbeous Vireo
Vireo plumbeus
The plumbeous vireo is 12.4 to 13.8 cm (4.9 to 5.4 in) long and weighs about 12 to 20 g (0.42 to 0.71 oz). The sexes have the same plumage. Adults of the nominate subspecies V. p. plumbeus have a neutral gray crown and nape, a wide white stripe above the lores, a wide white eye-ring, a dusky stripe through the eye-ring, and neutral gray ear coverts. Their upperparts are neutral gray with an olive-green tinge on the rump. Their wing coverts are blackish gray with whitish tips that show as two wing bars. Their remiges are blackish gray with pale olive gray edges. Voice: The male plumbeous vireo's primary song is a "jerky series of burry phrases, separated by pauses often alternates between ascending and descending phrases: ch'reeh ch'roo ch'reeh ch'roo or ch'ree chi-ri'eet ch'ree ch'ree-oo". Another song is a "complicated jumble of chattering, warbling, and singing in rapid and apparently random combinations". The species' calls include an "rasping chatter...
ID text from Wikipedia, CC BY-SA 4.0
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