The gray vireo (''Vireo vicinior'') is a small

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

passerine A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped') which includes more than half of all bird species. Sometimes known as perching birds, passerines generally have an anisodactyl arrangement of their ...

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

. It breeds from the southwestern

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

and northern

Baja California Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of B ...

to western

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

. It is a migrant, wintering in northwestern

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

, in western

Sonora Sonora (), officially Estado Libre y Soberano de Sonora (), is one of the 31 states which, along with Mexico City, comprise the Administrative divisions of Mexico, Federal Entities of Mexico. The state is divided into Municipalities of Sonora, 72 ...

state, and the southern Baja Peninsula in

Baja California Sur Baja California Sur, officially the Free and Sovereign State of Baja California Sur, is a state in Mexico. It is the 31st and last state to be admitted, in 1974. It is also the second least populated Mexican state and the ninth-largest state by ...

; it remains all year only in

Big Bend National Park Big Bend National Park is a List of national parks of the United States, national park of the United States located in West Texas, bordering Mexico. The park has national significance as the largest protected area of Chihuahuan Desert topograph ...

in southwest Texas. It is usually found at altitudes between in its Mexican breeding grounds. This vireo frequents dry brush, especially

juniper Junipers are coniferous trees and shrubs in the genus ''Juniperus'' ( ) of the cypress family Cupressaceae. Depending on the taxonomy, between 50 and 67 species of junipers are widely distributed throughout the Northern Hemisphere as far south ...

, on the slopes of the southwestern mountains.

Description

The gray vireo is in length, gray above, and dull white below, with a single faint wing bar and an eye-ring. It has a short, thick bill. Sexes are similar. The sideways twitching of its tail is unique among vireos and is reminiscent of that of gnatcatchers. The song is ''hu-wee, chu-wee, che-weet, chee, ch-churr-weet'', ''churr'', ''schray''.

Behavior

The gray vireo has skulking habits and is difficult to observe in the dense vegetation it inhabits which is mostly pinyon-juniper woodland or

scrub oak Scrub oak is a common name for several species of small, shrubby oaks. It may refer to: *the Chaparral plant community in California, or to one of the following species. In California *California scrub oak ('' Quercus berberidifolia''), a widesp ...

woodland. It feeds mainly on insects, and birds that overwinter in Mexico additionally consume fruit. Nests are built within of the ground, often in a thorny tree and consist of dry grasses, plant remains, shreds of bark and spider's web, lined with grasses and fine fibres. A clutch of three or four white eggs is laid and incubated by both parents for about thirteen days. The young leave the nest a fortnight later. Attempted parasitism by the

brown-headed cowbird The brown-headed cowbird (''Molothrus ater'') is a small, obligate brood parasitic icterid native to temperate and subtropical North America. It is a permanent resident in the southern parts of its range; northern birds migrate to the souther ...

(''Molothrus ater'') often causes the nest to be abandoned.

References

External links

Gray Vireo photo gallery
VIRE
Photo-High Res--(Close-up)Photo-High Res
{{Taxonbar, from=Q2667713 gray vireo Endemic birds of Southwestern North America Native birds of the Southwestern United States Meso-American wintering birds Fauna of the Sonoran Desert Fauna of the Chihuahuan Desert Birds of the Rio Grande valleys gray vireo