vireo

vireo, small, migratory songbird of the New World. Some species nest in the United States, but the majority are tropical. Vireos (also called greenlets) range from 4 to 6 1/2 in. (10.2–16.5 cm) in length; they are greenish above and white or yellowish below and have either stripes above or rings around the eyes. They search methodically through vegetation for insects. Vireos are known for their loud, persistent call and for their cup-shaped nest that is suspended in the fork of a tree limb. American vireos include the red-eyed, white-eyed, warbling, Philadelphia, yellow-throated, and blue-headed, or solitary, vireos. Vireos are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Passeriformes, family Vireonidae, genus Vireo.

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vireo

Any of 42 species (family Vireonidae) of New World songbirds with a stout, slightly notched, hook-tipped bill that has fine bristles at the base. Vireos are 4–7 in. (10–18 cm) long and are plain gray or greenish, with white or yellow touches. They glean insects from foliage in woodlands and thickets, repeating loud short phrases over and over. The nest is a cuplike structure suspended from a small fork in a branch. The red-eyed vireo (Vireo olivaceus), which breeds from southern Canada to Argentina, is 6 in. (15 cm) long and has a black-outlined, white eye stripe that contrasts with its gray crown.