About Elaenia albiceps (Orbigny & Lafresnaye, 1837)
The white-crested elaenia, Elaenia albiceps, is 13.5 to 15 cm (5.3 to 5.9 in) long and weighs 12.5 to 24.2 g (0.44 to 0.85 oz). It is a small to medium-sized elaenia with a small bushy crest. The sexes of this species have identical plumage. Adults of the nominate subspecies E. a. albiceps have a mostly dull olive to olive-gray head, with a partially hidden white or creamy white stripe running through the center of the crest. They have whitish lores and a whitish eyering. Their upperparts are dull olive to olive-gray. Their wings are dusky, with white or whitish tips on the coverts that form two distinct wing bars. Their flight feathers have narrow whitish or yellowish edges, and the inner pairs of flight feathers have dusky bases. Their tail is dusky, with narrow olive edges on each feather. Their throat is light gray or whitish gray, their breast is light gray or grayish brown, and their belly and undertail coverts are whitish. The other recognized subspecies differ from the nominate and from each other as follows: E. a. griseigularis has paler upperparts than the nominate, with less white on a shorter crest and a less distinct eyering. E. a. diversa is similar to griseigularis, but has a whiter throat, less distinct wing bars, and greater contrast between the flanks and belly. E. a. urubambae has paler upperparts than the nominate, with paler lores, a less prominent eyering, duller wing bars, and a pale yellow wash on the belly. E. a. modesta is duller overall than the nominate, with no distinct contrast between the lores and eyering, less distinct wing bars, and pale edges on the inner flight feathers that extend through the area that is dusky on the nominate. Both sexes of all subspecies have a dark brown iris, a black or dark gray bill with a pale base to the mandible, and black or dark gray legs and feet. Elaenias classified as white-crested elaenia by the South American Classification Committee (SACC) have been recorded as vagrants on the Falkland Islands, with no subspecies identification. This means the vagrant individuals could have been Chilean elaenia, a species recognized by the International Ornithological Congress (IOC) but not by the SACC. Chilean elaenia is highly migratory. The habitat requirements of all subspecies of white-crested elaenia except E. a. modesta have been studied, and E. a. modesta is assumed to have similar habitat requirements to the other subspecies. White-crested elaenia inhabit the edges of subtropical and temperate forest, the interior of open woodlands and secondary forest, and scrublands. In many regions, the species favors drier intermontane valleys over the higher slopes above them. Its elevation range varies by country: it occurs up to 3,200 m (10,500 ft) in Colombia, between 1,500 and 2,800 m (4,900 and 9,200 ft) in Ecuador, between 800 and 3,500 m (2,600 and 11,500 ft) on Peru's west slope, and between 1,000 and 3,300 m (3,300 and 10,800 ft) on Peru's east slope.
