Mangrove vireo
The mangrove vireo is a species of bird in the family Vireonidae, the vireos, greenlets, and shrike-babblers. It is found Mexico and every Central American country except Panama.
Taxonomy and systematics
The mangrove vireo was formally described in 1863 by the English naturalist Osbert Salvin based on specimens collected at El Realejo in Nicaragua and at Puntarenas in Costa Rica. He coined the current binomial Vireo pallens. The specific epithet is from Latin meaning "pale-colored", "greenish" or "yellowish". El Realejo has been designated the type locality.The mangrove vireo's taxonomy is unsettled. The IOC, AviList, and BirdLife International's Handbook of the Birds of the World assign it these 10 subspecies:V. p. paluster Moore, RT, 1938V. p. semiflavus Salvin, 1863V. p. ochraceus Salvin, 1863V. p. salvini Van Rossem, 1934V. p. pallens Salvin, 1863V. p. wetmorei Phillips, AR, 1991V. p. angulensis Parkes, 1990V. p. browningi Phillips, AR, 1991V. p. nicoyensis Parkes, 1990V. p. approximans Ridgway, 1884
The Clements taxonomy does not recognize V. p. wetmorei and V. p. browningi, including them within V. p. semiflavus.
Some twentieth century authors treated the mangrove vireo as conspecific with the white-eyed vireo. Others have suggested that two or three species are represented within the mangrove vireo because of plumage and vocal differences between the "Pacific" and "Caribbean" groups of subspecies.
Subspecies V. p. approximans was originally described by Robert Ridgway as a species. Ridgway noted the bird's strong similarity to what is now the thick-billed vireo. Until the late 2010s approximans was treated as a subspecies of crassirostris before taxonomic systems began transferring it to its present position as a subspecies of V. pallens.
This article follows the 10-subspecies model.
Description
The mangrove vireo is long and weighs about. The sexes have the same plumage. Adults of the nominate subspecies V. p. pallens have a mostly greenish brown crown, face, and nape with a buffy area from above the lores to past the eye. Their upperparts are greenish brown. Their wing coverts are dark gray with yellowish white tips that form two wing bars. Their flight feathers are dark gray; the primaries and secondaries have thin yellowish green edges on the outer webs and the tertials have whitish edges. Their tail is dark gray with greenish edges on the feathers' outer webs. Their chin is whitish yellow and their throat and underparts grayish with a faint yellow tinge on the lower flanks and belly.The other subspecies of the mangrove vireo differ from the nominate and each other thus:V. p. paluster: larger than nominate with yellower underpartsV. p. semiflavus: brighter greenish upperparts and brighter yellow underparts than all other subspeciesV. p. ochraceus: like the nominate with a dull yellow irisV. p. salvini: smaller and paler than nominate with greenish olive upperparts and yellowish underpartsV. p. wetmorei: like semiflavusV. p. angulensis: smaller than nominate, with brownish drab cheeks and a pale olive back with a drab brownish washV. p. browningi: like semiflavusV. p. nicoyensis: paler and duller overall than other subspecies, with almost pure white throat and belly and a highly variable iris color from light brown to whiteV. p. approximans: yellowish breast; larger and wider bill than others
The mangrove vireo's subspecies have a brownish straw to dirty white iris, a dark brown or gray brown maxilla, a paler mandible, and gray-blue legs and feet.
Distribution and habitat
The mangrove vireo has a widely disjunct distribution. The subspecies are found thus:V. p. paluster: coastal northwestern Mexico from southwestern Sonora south to NayaritV. p. semiflavus: from northern Guatemala and southern Belize south across northern Honduras into eastern Nicaragua to BluefieldsV. p. ochraceus: from southern Oaxaca in southwestern Mexico south along the Pacific coast through Guatemala into El Salvador's Usulután DepartmentV. p. salvini: southeastern Mexico's Yucatán Peninsula and northern BelizeV. p. pallens: southern Honduras, western Nicaragua, and western Costa RicaV. p. wetmorei Isla El Cayo off eastern GuatemalaV. p. angulensis: the Bay Islands off north HondurasV. p. browningi: southeastern NicaraguaV. p. nicoyensis: Nicoya Peninsula and around the Bay of Nicoya in northwestern Costa RicaV. p. approximans: Isla de Providencia and Isla Santa Catalina off the east coast of NicaraguaThe mangrove vireo inhabits different landscapes on the Pacific and Caribbean sides. The Pacific subspecies V. p. paluster, V. p. ochraceus, V. p. pallens, and V. p. nicoyensis are found almost exclusively in mangroves, especiall red mangrove. The other subspecies, found along the Caribbean coast and nearby islands, inhabits more varied landscapes. In addition to mangroves these include scrubby woodlands, fields being overgrown with bushes, young secondary forest, and the edges of more mature forest.