The straight-billed earthcreeper (''Ochetorhynchus ruficaudus'') 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 found in

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Bolivia Bolivia, officially the Plurinational State of Bolivia, is a landlocked country located in central South America. The country features diverse geography, including vast Amazonian plains, tropical lowlands, mountains, the Gran Chaco Province, w ...

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 ...

, and

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Taxonomy and systematics

The straight-billed earthcreeper has these three subspecies: *''O. r. montanus'' (

d'Orbigny Alcide Charles Victor Marie Dessalines d'Orbigny (6 September 1802 – 30 June 1857) was a French naturalist who made major contributions in many areas, including zoology (including malacology), palaeontology, geology, archaeology and anthropol ...

& Lafresnaye, 1838) *''O. r. famatinae'' (Nores, 1986) *''O. r. ruficaudus'' Meyen, 1834 For a time the straight-billed earthcreeper was placed in genus '' Upucerthia'' but since the early 2000s has been in its present genus.Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, G. Del-Rio, A. Jaramillo, D. F. Lane, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 31 May 2023. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved May 31, 2023

Description

The straight-billed earthcreeper long and weighs . It is a medium-sized earthcreeper whose bill is long and only very slightly decurved. The sexes are alike. 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. r. ruficaudus'' have a dull brownish face with some paler inclusions, 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 ...

, a black stripe through the eye, and whitish cheeks. In the north of their range their crown is brown with slight darker mottling, their back and rump rufescent brown, and their 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 ...

dark rufescent. In the south their upperparts are darker and less reddish. Their tail's central pair of feathers have a rufous base that blends to blackish tips and the outermost pair are mostly rufous. The feathers between them have mostly blackish-brown inner webs and dark rufous outer webs. Their throat is whitish, their breast whitish with faint dull brownish streaks, their flanks and belly pale rufescent browish with some whitish streaks on the upper belly, and their undertail coverts tawny. Their iris is brown, their bill black or blackish brown with a whitish horn base to the

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 ...

, and their legs and feet black or blackish brown. Juveniles have an overall rufous tinge and pale edges on their crown and back feathers.Remsen, Jr., J. V. (2020). Straight-billed Earthcreeper (''Ochetorhynchus ruficaudus''), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.stbear2.01 retrieved August 18, 2023 Subspecies ''O. r. montanus'' has a whiter throat and breast than the nominate with more conspicuous streaks on the sides and flanks. ''O. r. famatinae'' has a slightly darker back than the nominate, a whiter breast, and darker flanks and undertail coverts.

Distribution and habitat

The straight-billed earthcreeper is a bird of the southern Andes. Subspecies ''O. r. montanus'' is the most northerly. It is found from the

Department of Arequipa Arequipa () is a department and region in southwestern Peru. It is the sixth largest department in Peru, after Puno, Cuzco, Madre de Dios, Ucayali, and Loreto, its sixth most populous department, and its eleventh least densely populated dep ...

in southern Peru into northern Chile to the

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, and east and south though Bolivia from La Paz Department into northern Argentina as far as

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. The nominate ''O. r. ruficaudus'' is found in western Argentina between

San Juan San Juan, Spanish for Saint John (disambiguation), Saint John, most commonly refers to: * San Juan, Puerto Rico * San Juan, Argentina * San Juan, Metro Manila, a highly urbanized city in the Philippines San Juan may also refer to: Places Arge ...

and extreme northern Santa Cruz provinces and in adjoining Chile as far south as the

Santiago Metropolitan Region Santiago Metropolitan Region () is one of Chile's 16 first-order administrative divisions. It is the country's only landlocked administrative region and contains the nation's capital, Santiago. Most commercial and administrative centers are loc ...

. ''O. r. famatinae'' is restricted to the Sierra de Famatina in northwestern Argentina's La Rioja Province. The straight-billed earthcreeper inhabits arid scrublands with bunchgrass and scattered bushes. It favors rocky hillsides, rocky outcrops, and ravines. In elevation it mostly ranges between though it is common down to and occurs locally as low as .

Behavior

Movement

The straight-billed earthcreeper is a year-round resident throughout its range.

Feeding

The straight-billed earthcreeper forages on the ground for its

arthropod Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...

diet, usually singly but also in pairs. It gleans and extracts its prey while hopping among the rocks, bunchgrass, and bushes of its habitat.

Breeding

The straight-billed earthcreeper is thought to be monomgamous. It breeds in the austral summer, mostly between November and February. It excavates a tunnel in an earthen bank or occupies a rock crevice, and lines the nest chamber with soft material such as grass, hair, and feathers. The clutch size is two eggs. The incubation period, time to fledging, and details of parental care are not known.

Vocalization

The straight-billed earthcreeper's song is a loud series of notes that first rises in pitch and then slowly descends and fades away. Its call is "a sharp 'kweep' or 'wheet' ".

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 straight-billed earthcreeper as being of Least Concern. It has a fairly large range but its population size is not known and is believed to be decreasing. No immediate threats have been identified. It is considered fairly common throughout its range and is "reasonably safe from anthropogenic disturbances, except overgrazing".

References

{{Taxonbar, from=Q1264250 straight-billed earthcreeper Birds of Argentina Birds of the Puna grassland Birds of the Southern Andes straight-billed earthcreeper Taxonomy articles created by Polbot