Brown-capped Vireo
Vireo leucophrys
The brown-capped vireo is 11.5 to 12.5 cm (4.5 to 4.9 in) long and weighs about 12 to 13.5 g (0.42 to 0.48 oz). The sexes have the same plumage. Adults of the nominate subspecies V. l. leucophrys have an olive-brown crown, a white supercilium, a dusky spot on their lores, a dusky streak behind the eye, and grayish white ear coverts. Their upperparts, wings, and tail are grayish olive to brownish olive-green with yellow edges on the wing coverts. Their throat and upper breast are grayish white and the rest of their underparts pale yellow. Voice: The brown-capped vireo's song has been described as "a short, sweet 2.5-3-sec. warble, similar to Warbling Vireo song", "a silky, ripping, and somewhat hurried little refrain, here you sée me hear me sing so swéet", and "a hesitating, pleasant warble of variable pattern...wurlze-wee-wee wurzle-weezle-wee wurzle-wee". One description of its call is "a wheezing, descending zreeEEEEw".
ID text from Wikipedia, CC BY-SA 4.0
Yellow-green Vireo
Vireo flavoviridis
The adult yellow-green vireo is 14–14.7 cm in length and weighs 18.5 g. It has olive-green upperparts and a dusky-edged gray crown. There is a dark line from the bill to the red-brown eyes, and a white supercilium. The underparts are white with yellow breast sides and flanks. Young birds are duller with brown eyes, a brown tint to the back, and less yellow on the underparts. The adult yellow-green vireo differs from the red-eyed vireo in its much yellower underparts, lack of a black border to the duller gray crown, yellower upperparts and different eye color.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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