Plumbeous vireo
The plumbeous vireo is a small North American songbird in the family Vireonidae, the vireos, greenlets, and shrike-babblers. It is found from the U. S. states of Montana and South Dakota south to Honduras.
Taxonomy and systematics
The plumbeous vireo was originally described in 1866 as Vireo plumbeous, its present binomial. Until the late 1990s it and what are now Cassin's vireo and the blue-headed vireo were treated as a single species, the "solitary vireo". Earlier studies had suggested the split based on morphology, plumage, and vocalizations, and molecular genetic studies published in the early 1990s confirmed differences among the three. They form a superspecies.The plumbeous vireo has these four subspecies:V. p. plumbeus Coues, 1866V. p. gravis Phillips, AR, 1991V. p. notius Van Tyne, 1933V. p. montanus Van Rossem, 1933
Several other subspecies have been named but have not been confirmed as separate from any of these four. There is some doubt about whether V. plumbeous represents one or two species, and the Clements taxonomy separates them within the species as the "plumbeous" and "Central American" plumbeous vireos.
Description
The plumbeous vireo is long and weighs about. 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. Their rectrices are blackish gray with wide white edges on the outermost pair. Their underparts are mostly nearly white with smudgy pale grayish olive on the sides of the breast and, in some individuals, very pale sulfur yellow on the flanks.Subspecies V. p. gravis is larger than the nominate with a darker crown and more olive edges on the secondaries. V. p. notius is mostly like the nominate though some individuals have a somewhat greener back and yellower flanks. V. p. montanus has a blue-gray crown, a greenish back, and greenish yellow flanks. All subspecies have a brown iris, a black bill with a grayish base to the mandible, and bluish gray legs and feet.
Distribution and habitat
The plumbeous vireo has a disjunct distribution. The subspecies are found thus:V. p. plumbeus: west-central U. S. in southeastern Montana, southwestern South Dakota, and from south-central Idaho, northeastern Utah, and Wyoming south through Nevada, eastern California, Arizona, western Colorado and New Mexico, and extreme western Texas into Mexico as far as Guerrero and south-central OaxacaV. p. gravis: east-central Mexico in Hidalgo, western Veracruz, and PueblaV. p. notius: BelizeV. p. montanus: from southeastern Oaxaca and Chiapas south through central Guatemala and Honduras into northern NicaraguaThe species has also occurred casually or accidentally in Oregon, Louisiana, and a few other locations.
The plumbeous vireo inhabits a variety of landscapes in the temperate and subtropical zones. In the U. S. it primarily is found in coniferous and mixed pine-oak forests including those dominated by ponderosa pine and piñon-juniper complexes. It also occurs in riparian woodlands. Further south into Mexico it mostly occurs in pine-oak and oak scrublands. In migration and when overwintering it inhabits a greater variety, adding gallery forest, mangroves, plantations, evergreen forest, and thorn forest. In Belize, Guatemala, and Honduras it inhabits pine-oak forest and pine savanna. In its breeding range it is found at elevations between and in Mexico from sea level to. In Central America it mostly occurs above except in eastern Honduras where it is found at or below.