The chestnut-breasted wren (''Cyphorhinus thoracicus'') is a species of

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...

in the family Troglodytidae. It is found in

Colombia Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the Car ...

Ecuador Ecuador ( ; ; Quechua: ''Ikwayur''; Shuar: ''Ecuador'' or ''Ekuatur''), officially the Republic of Ecuador ( es, República del Ecuador, which literally translates as "Republic of the Equator"; Quechua: ''Ikwadur Ripuwlika''; Shuar: ''Eku ...

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

and

Bolivia , image_flag = Bandera de Bolivia (Estado).svg , flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center , flag_alt2 = 7 × 7 square p ...

Taxonomy and systematics

The

International Ornithological Committee The International Ornithologists' Union, formerly known as the International Ornithological Committee, is a group of about 200 international ornithologists, and is responsible for the International Ornithological Congress and other international ...

(IOC), the

Clements taxonomy ''The Clements Checklist of Birds of the World'' is a book by Jim Clements which presents a list of the bird species of the world. The most recent printed version is the sixth edition (2007), but has been updated yearly, the last version in 2022 ...

, and the South American Classification Committee of the

American Ornithological Society The American Ornithological Society (AOS) is an ornithological organization based in the United States. The society was formed in October 2016 by the merger of the American Ornithologists' Union (AOU) and the Cooper Ornithological Society. Its m ...

(SACC/AOS) treat the chestnut-breasted wren as one species with two subspecies, the nominate ''Cyphorhinus thoracicus thoracicus'' and ''C. t. dichrous''.Clements, J. F., T. S. Schulenberg, M. J. Iliff, S. M. Billerman, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2019. The eBird/Clements Checklist of Birds of the World: v2019. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/ Retrieved August 15, 2019

BirdLife International BirdLife International is a global partnership of non-governmental organizations that strives to conserve birds and their habitats. BirdLife International's priorities include preventing extinction of bird species, identifying and safeguarding ...

(BLI) treats them as separate species, the southern and northern chestnut-breasted wrens respectively.HBW and BirdLife International (2020) ''Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world'' Version 5. Available at: http://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v5_Dec20.zip xls zipped 1 MBretrieved May 27, 2021

Description

The nominate ("southern") subspecies of chestnut-breasted wren is long and weighs . The "northern" ''C. t. dichrous'' is long; males weigh and females . They appear very similar. The nominate adult has a sooty black crown, a rich dark brown back and rump, and a dark brown tail. ''C. t. dichrous''s crown is black, its back and rump very dark brown, and its tail dark brown. Both have deep orange-brown faces, throat, and upper belly and dark brown flanks and lower belly. Both juveniles differ from the adults only in having a paler lower belly.Kroodsma, D. E., J. del Hoyo, D. Brewer, N. Collar, and G. M. Kirwan (2020). Chestnut-breasted Wren (''Cyphorhinus thoracicus''), version 1.0. In Birds of the World (S. M. Billerman, B. K. Keeney, P. G. Rodewald, and T. S. Schulenberg, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.chbwre1.01 retrieved July 19, 2021

Distribution and habitat

The "northern" ''C. t. dichrous'' is found in the Western and Central Andes of Colombia and south through Ecuador into northern Peru. The "southern" ''C. t. thoracicus'' is found in central Peru and western Bolivia. The chesnut-breasted wren inhabits wet

montane forest Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial f ...

including

cloud forest A cloud forest, also called a water forest, primas forest, or tropical montane cloud forest (TMCF), is a generally tropical or subtropical, evergreen, montane, moist forest characterized by a persistent, frequent or seasonal low-level cloud c ...

with abundant

epiphyte An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

s and moss. In elevation the "northern" subspecies usually ranges between but is found as low as on the Pacific side of the Western Andes. The "southern" subspecies is mostly found between but down to in Peru's

Manú Province Manú Province is one of three provinces in the Madre de Dios Region of Peru. Instituto Nacional de Estadística e InformáticaBanco de Información Digital, Retrieved January 5, 2008 The capital of Manú province is the city of Salvación. Polit ...

Behavior

Feeding

The chestnut-breasted wren typically remains within of the ground, foraging in leaf litter for invertebrates such as beetles and spiders. It hunts alone, in pairs, or in what are assumed to be small family groups. It only rarely joins mixed-species foraging flocks.

Breeding

Little is known about the chesnut-breasted wren's breeding

phenology Phenology is the study of periodic events in biological life cycles and how these are influenced by seasonality, seasonal and interannual variations in climate, as well as environmental factor, habitat factors (such as elevation). Examples includ ...

. Its nesting season appears to differ regionally; overall it is protracted. One nest in Peru has been photographed; it was a domed structure of mostly live material set very close to the ground. It contained two eggs.

Vocalization

The songs of the two chesnut-breasted wren subspecies differ significantly. That of the "southern" ''C. t. thoracicus'' is "a variable, musical and usually unhurried series... ffluted whistles that differ from each other in pitch, which are then followed by a faster-paced series of 5–11 short whistles...or by a much faster trilled tremolo." Its call is "a low, somewhat frog-like and wooden 'krol'". The song of ''C. t. dichrous'' is "a series of usually 3–4 ethereal, clear whistled notes" and its call "a harsh 'churr'".

Status

The

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

treats the two subspecies separately and has assessed both as being of Least Concern. The species is quite common in parts of Colombia, scarce in Ecuador, uncommon to locally common in Peru, and rare to uncommon in Bolivia. It does occur in several protected areas.