Chilean elaenia


The Chilean elaenia is a species of bird in subfamily Elaeniinae of family Tyrannidae, the tyrant flycatchers. It is found in Argentina, Bolivia, Brazil, Chile, Colombia, Paraguay, Peru, and Uruguay.

Taxonomy and systematics

The International Ornithological Committee treats the Chilean elaenia as a monotypic species. The South American Classification Committee of the American Ornithological Society, the Clements taxonomy, and BirdLife International's Handbook of the Birds of the World consider it a subspecies of the white-crested elaenia. The SACC is seeking a proposal to recognize it as a species.

Description

The Chilean elaenia is long. It is a small to medium size elaenia with a small bushy crest. The sexes have the same plumage. Adults have a mostly dark olive to olive-gray head with a partially hidden white stripe in the middle of the crest. They have white lores and a bold white eyering. Their upperparts are dark olive to olive-gray. Their wings are dusky with white or whitish tips on the coverts that show as two wing bars. Their flight feathers have narrow whitish or yellowish edges with dusky bases on the inner pairs. Their tail is dusky with narrow olive edges to the feathers. Their throat is whitish gray, their breast very light gray, and their belly and undertail coverts whitish.

Distribution and habitat

The Chilean elaenia breeds from southern Bolivia south through Chile and southern Argentina into Tierra del Fuego. Its distribution in the austral winter is not fully understood but it appears to leave almost all if its breeding range and move east across Argentina to the Atlantic, north through Peru east of the Andes and just into far southeastern Colombia, and northeast through northern Argentina, Uruguay, Paraguay, and much of Brazil as far as Bahia and Pará. One showed up as a vagrant in southern Texas in 2008.
In the far south the Chilean elaenia inhabits Nothofagus and Araucaria woodlands and scrublands. Further north in its breeding range and in its wintering range it inhabits the edges of forest, the interior of more open woodlands and secondary forest, and scrublands.

Behavior

Feeding

The Chilean elaenia's diet has not been detailed but is known to include insects and fruit. It typically forages singly. It captures prey and plucks fruit by gleaning while perched and while briefly hovering.

Breeding

The few known nests of the Chilean elaenia were a small cup made from plant fibers, leaves, lichens, moss, and small twigs and lined with feathers or plant down. They were typically place in a branch fork in a tree or shrub. One was in a cavity, the only known such placement for a member of genus Elaenia. The clutch is two or three eggs that are creamy white with sparse red spots. The incubation period, time to fledging, and details of parental care are not known.

Vocalization

The Chilean elaenia's dawn song is "a short, slightly raspy two- or three-note phrase". Its call in its breeding range and perhaps beyond is "feeeo or feeo-feeo" that may be repeated for a long time. Other calls are "a pure, descending weer, a burry, sneezing whi'bur, and a burry, rising chjuree?".

Status

The IUCN follows HBW taxonomy and so has not assessed the Chilean elaenia separately from the white-crested elaenia. "A species that occupies forest edge and second-growth, it is likely that this species is relatively tolerant of habitat disturbance. That said, at least a portion of the population winters in northeastern Brazil, a region that has undergone widespread habitat loss due to conversion of natural habitats to agriculture."