Vireo (genus)

Template:Short description Template:Automatic taxobox Vireo is a genus of small passerine birds restricted to the New World. Vireos typically have dull greenish plumage (hence the name, from Latin virere, "to be green"), but some are brown or gray on the back and some have bright yellow underparts. They resemble wood warblers apart from their slightly larger size and heavier bills, which in most species have a very small hook at the tip. The legs are stout.

Most species fall into two plumage groups: one with wing bars and yellow or white eye rings, and one with unmarked wings and eye stripes; however, the Chocó vireo has both wing bars and eye stripes.

Sexes are alike in all species except for the black-capped vireo, in which the male's crown is black and the female's is gray.

Taxonomy

The genus Vireo was introduced in 1808 by the French ornithologist Louis Pierre Vieillot. The type species was subsequently designated as the white-eyed vireo (Vireo griseus) by German ornithologist Hans Friedrich Gadow in 1883. The word vireo was used by Latin authors for a small, green, migratory bird, probably a Eurasian golden oriole, but a European greenfinch has also been suggested.

Feeding

All members of the genus mostly eat insects and other arthropods, but also eat some fruit. A common pattern is arthropods in summer and fruit in winter. Vireos take prey from leaves and branches and in midair, and the gray vireo takes 5% of its prey from the ground.

Range and territorial behavior

Most species are found in Central America and northern South America. Thirteen species occur farther north, in the United States, Canada, and Bermuda; of these, all but Hutton's vireo are migratory. Vireos seldom fly long distances except in migration.

The resident species occur in pairs or family groups that maintain territories all year (except Hutton's vireo, which joins mixed feeding flocks). Most of the migrants defend winter territories against conspecifics. The exceptions are the complex comprising the red-eyed vireo, the yellow-green vireo, the black-whiskered vireo, and the Yucatan vireo, which winter in small, wandering flocks.

Voice and breeding

Males of most species are persistent singers. Songs are usually rather simple, ranging from monotonous, in some species of the Caribbean littoral and islands, to elaborate and pleasant to human ears in the Chocó vireo. Calls often include "scolding chatters and mews".

File:SolitaryVireo23.jpg

Blue-headed vireo

The species whose nests are known all build a cup-shaped nest that hangs from branches. Its outer layer is made of coarse leaf and bark strips or of moss, depending on the species; in either case, the material is bound with spider silk and ornamented with spider egg cases. The lining is made of fine grass stems neatly circling the cup. In most species, both sexes work on the nest, but the female adds the lining. In the red-eyed, black-whiskered, Yucatan, and Philadelphia vireos, the male does not help, instead singing and accompanying the female while she builds the nest. The female does most of the incubation, spelled by the male except in the red-eyed vireo complex.

The eggs are whitish; all but the black-capped and dwarf vireos have sparse, fine brown or red-brown spots at the wide end. Tropical species lay two, while temperate-zone species lay four or five. Incubation lasts 11 to 13 days, and the young fledge after the same amount of time. Both sexes feed the nestlings arthropods, and each fledgeling is fed by one parent or the other (not both) for as long as 20 days.

Species

The genus contains 34 species:

Group	Image	Scientific name	Common Name	Distribution
The "hypochryseus" group	File:Golden Vireo.jpg	Golden vireo	Vireo hypochryseus	Mexico
The "olivaceous" group	File:Yellow-green Vireo - Carara - Costa Rica S4E0062 (26670622936).jpg	Yellow-green vireo	Vireo flavoviridis	southern Texas, Mexico (the Sierra Madre Occidental and Sierra Madre Oriental—also the Cordillera Neovolcanica) south to central Panama
	File:Red-eyed Vireo (8577463371).jpg	Red-eyed vireo	Vireo olivaceus	Canada and the eastern and northwestern United States, Argentina, Uruguay, Paraguay and Bolivia
	File:Yucatan Vireo (6842666740).jpg	Yucatan vireo	Vireo magister	Belize, Honduras, Mexico
	File:Vireo altiloquus Martinique.jpg	Black-whiskered vireo	Vireo altiloquus	southern Florida, USA, and the West Indies as far south as the offshore islands of Venezuela
	File:Vireo chivi, Vale do Ribeira, Registro, Sao Paolo, Brasil.jpg	Chivi vireo	Vireo chivi	northeastern Colombia, into Venezuela and the entirety of the Guianas into eastern Brazil
	File:Vireo gracilirostris - Noronha vireo.jpg	Noronha vireo	Vireo gracilirostris	Fernando de Noronha, Brazil
The "gilvus" group		Tepui vireo	Vireo sclateri	western Guyana and northern Brazil
	File:Philadelphia Vireo (14067191614).jpg	Philadelphia vireo	Vireo philadelphicus	Canada to Central America
	File:Warbling Vireo 0800vv.jpg	Warbling vireo	Vireo gilvus	Alaska to Mexico and the Florida Panhandle
	File:Brown-capped Vireo - South Ecuador S4E8717 (22991156292).jpg	Brown-capped vireo	Vireo leucophrys	Southern Mexico south to northwestern Bolivia
The "eye-ringed" group	File:Hutton's Vireo 4842.jpg	Hutton's vireo	Vireo huttoni	southern British Columbia in Canada to central Guatemala in Central America
	File:Vireo vicinior.jpg	Gray vireo	Vireo vicinior	southwestern United States and northern Baja California to western Texas
	File:Yellow-throated Vireo by Dan Pancamo 1.jpg	Yellow-throated vireo	Vireo flavifrons	southern United States, Mexico, the Caribbean, and Central America
	File:Yellow-winged Vireo (Vireo carmioli) (5772476424) (cropped).jpg	Yellow-winged vireo	Vireo carmioli	Costa Rica and western Panama
	File:Vireo masteri 17620880 (cropped).jpg	Choco vireo	Vireo masteri	western Colombia and north-west Ecuador
	File:Vireo solitarius Sam Smith Park Toronto.jpg	Blue-headed vireo	Vireo solitarius	Canada and northern United States
	File:Cassin's Vireo Las Cruces.jpg	Cassin's vireo	Vireo cassinii	southern British Columbia in Canada through the western coastal states of the United States.
	File:Plumbeous Vireo DSC 8172vv.jpg	Plumbeous vireo	Vireo plumbeus	southeastern Montana and western South Dakota south to the Pacific coast of Mexico
	File:Blue Mountain Vireo (Vireo osburni) (6499241641).jpg	Blue Mountain vireo	Vireo osburni	Jamaica
	File:Vireo nanus imported from iNaturalist photo 58199583 on 3 April 2021.jpg	Flat-billed vireo	Vireo nanus	Hispaniola
	File:Vireo pallens.jpg	Mangrove vireo	Vireo pallens	Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, and Nicaragua
	File:Providencia Vireo imported from iNaturalist photo 14639954 on 29 February 2024.jpg	Providencia vireo	Vireo approximans	Isla de Providencia
	File:Vireo bairdi 264382156.jpg	Cozumel vireo	Vireo bairdi	Mexico
	File:San Andres Vireo (Vireo caribaeus) (cropped).jpg	San Andres vireo	Vireo caribaeus	islands of St. Andrew (or San Andrés) and Providencia
	File:Edit white-eyed vireo blandair 4.20.20 DSC 0224.jpg	White-eyed vireo	Vireo griseus	eastern United States from New England west to northern Missouri and south to Texas and Florida, and also in eastern Mexico, northern Central America, Cuba and the Bahamas
	File:Thick-billed Vireo on twig.jpg	Thick-billed vireo	Vireo crassirostris	West Indies in the Bahamas, Turks and Caicos Islands, Cayman Islands, Tortuga Island in Haiti and Cuba
		Jamaican vireo	Vireo modestus	Jamaica
	File:Cuban Vireo - Cuba S4E0897 (22991166932).jpg	Cuban vireo	Vireo gundlachii	Cuba
	File:Bell's Vireo (34056428355).jpg	Bell's vireo	Vireo bellii	Western North America and Central America
	File:Vireo latimeri 184651046.jpg	Puerto Rican vireo	Vireo latimeri	Puerto Rico
	File:Black-capped Vireo - Texas - Usa H8O1970 (22978591836).jpg	Black-capped vireo	Vireo atricapilla	south from south-central Kansas through central Oklahoma and Texas to central Coahuila, Mexico
	File:Dwarf Vireo (Vireo nelsoni).jpg	Dwarf vireo	Vireo nelsoni	Mexico
	File:Slaty Vireo - Oaxaca - Mexico S4E9941 (22586261657).jpg	Slaty vireo	Vireo brevipennis	southern Mexico