The crag chilia or crag earthcreeper (''Ochetorhynchus melanurus'') is a species of

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 ...

in the Furnariinae subfamily of the ovenbird

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Furnariidae. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

Taxonomy and systematics

The crag chilia was formerly placed in its own genus, ''Chilia''. It is now placed in genus ''Ochetorhynchus'' with the straight-billed earthcreeper (''O. ruficaudus''), the rock earthcreeper (''O. andaecola''), and the band-tailed earthcreeper (''O. phoenicurus''). Two subspecies are recognized, ''O. m. melanurus'' and ''O. m. atacamae''.

Description

The crag chilia is long and weighs . Adults of the

nominate subspecies In biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics ( morphology), but that can successfully interbreed. ...

''O. m. melanurus'' have a narrow whitish

supercilium The supercilium is a plumage feature found on the heads of some bird species. It is a stripe which runs from the base of the bird's beak above its eye, finishing somewhere towards the rear of the bird's head.Dunn and Alderfer (2006), p. 10 Also k ...

, dark brown lores and auriculars, and whitish cheeks. Their upperparts are mostly darkish brown with a rufous rump and uppertail

coverts A covert feather or tectrix on a bird is one of a set of feathers, called coverts (or ''tectrices''), which cover other feathers. The coverts help to smooth airflow over the wings and tail. Ear coverts The ear coverts are small feathers behind t ...

. Their tail is mostly blackish brown with some rufous at the base and outer web of the outermost pair of feathers. Their upperwing coverts are dusky brown and their wings are darkish brown with a wide rufous band. Their throat is whitish, their breast dull smoky grayish, their belly dull brown, and their flanks and undertail coverts rufous. Their iris is brown, their

maxilla In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxil ...

blackish, their

mandible In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...

pale gray with a blackish tip, and their legs and feet blackish. Juveniles have pale edges on their back feathers and faint barring on their underparts.Medrano, F., G. Contreras, C. Piñones, and J. V. Remsen, Jr. (2020). Crag Chilia (''Ochetorhynchus melanurus''), version 2.0. In Birds of the World (T. S. Schulenberg and B. K. Keeney, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.crachi1.02 retrieved August 18, 2023 Subspecies ''O. m. atacamae'' is paler and sandier than the nominate. Its supecilium is whiter and more distinct. Its upperwing coverts are grayish brown, its breast pale grayish with white streaks, and its flanks pale brown. Its bill is shorter and narrower.

Distribution and habitat

The crag chilia is endemic to north-central and central Chile. Subspecies ''O. m. atacamae'' is found from Huasco Province in the Atacama Region to the Coquimbo Region. ''O. m. melanurus'' is found further south, between San Felipe de Aconcagua Province in the

Valparaíso Region The Valparaíso Region (, ) is one of Chile's 16 Regions of Chile, first order administrative divisions.Valparaíso Region, 2006 With the country's second-highest population of 1,790,219 , and fourth-smallest area of , the region is Chile's sec ...

and

Colchagua Province Colchagua Province () is one of three provinces of the central Chilean region of O'Higgins (VI). Its capital is San Fernando. It is bordered on the north by Cachapoal Province, on the east by the Argentine Republic, on the south by Curicó ...

in the

O'Higgins Region The Libertador General Bernardo O'Higgins Region (, ), often shortened to O'Higgins Region (), is one of Chile's 16 first order administrative divisions. It is subdivided into three provinces. It is named in honour of Bernardo O'Higgins Riquel ...

. The crag chilia inhabits arid scrublands with shrubby rock hillsides and cliffs with sparse vegetation. There is no consensus on its elevational range. In the non-breeding season it occurs as low as sea level. In the breeding season, different authors place its upper limit between .

Behavior

Movement

The crag chilia's migration pattern has not been fully described but the species apparently moves from higher elevations to lower ones for the austral winter of May to August.

Feeding

The crag chilia's diet is predominantly arthropods such as

Orthoptera Orthoptera () is an order of insects that comprises the grasshoppers, locusts, and crickets, including closely related insects, such as the bush crickets or katydids and wētā. The order is subdivided into two suborders: Caelifera – gras ...

and

Lepidoptera Lepidoptera ( ) or lepidopterans is an order (biology), order of winged insects which includes butterflies and moths. About 180,000 species of the Lepidoptera have been described, representing 10% of the total described species of living organ ...

but also includes seeds and fruits such as those of '' Tristerix'' species and '' Ephedra chilensis''. It is usually a solitary forager that gleans from rocks and bushes and also probes crevices.

Breeding

The species is presumed to be monogamous and its nesting season to be the austral spring and summer of September to March. At least in ''atacamae'' pairs establish as early as June. The nest is a bulky ball of sticks lined with feathers and is usually placed in a rock cavity, though some have been found in holes in earth banks and rural buildings. The clutch is three or four eggs. The incubation period and time to fledging are not known. Both parents provision nestlings.

Vocalization

The crag chilia's song is "a short (1 second) staccato chatter of jumbled notes with 4–7 loud 'teet' notes in hemiddle". Its call is "a metallic, abrupt 'ch' or 'ch-ch', often given as continuous chatter".

Status

The

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

has assessed the crag chilia as being of Least concern. It has a somewhat limited range, and though its population size is not known it is believed to be stable. No immediate threats have been identified. It is considered relatively uncommon. It occurs in a few protected areas and hunting it is illegal.

References

{{Taxonbar, from=Q1274466

crag chilia The crag chilia or crag earthcreeper (''Ochetorhynchus melanurus'') is a species of bird in the Furnariinae subfamily of the ovenbird family Furnariidae. It is endemic to Chile. Taxonomy and systematics The crag chilia was formerly placed i ...

Birds of Chile Endemic birds of Chile

Taxonomy articles created by Polbot Fauna of the Chilean Matorral