The riverside wren (''Cantorchilus semibadius'') 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

Costa Rica Costa Rica (, ; ; literally "Rich Coast"), officially the Republic of Costa Rica ( es, República de Costa Rica), is a country in the Central American region of North America, bordered by Nicaragua to the north, the Caribbean Sea to the no ...

and

Panama Panama ( , ; es, link=no, Panamá ), officially the Republic of Panama ( es, República de Panamá), is a transcontinental country spanning the southern part of North America and the northern part of South America. It is bordered by Cos ...

Taxonomy and systematics

The riverside wren has sometimes been treated as conspecific with bay wren (''Cantorchilus nigricapillus'') but their plumages are quite different as are DNA analyses. The species is

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

.Kroodsma, D. E. and D. Brewer (2020). Riverside Wren (''Cantorchilus semibadius''), 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.rivwre1.01 retrieved June 7, 2021

Description

The riverside wren is long and weighs . The adults have a bright orange-brown crown; chestnut nape, back, and rump; and a blackish tail with buff-white bars. They have a black-over-white

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 ...

and the rest of the face is streaked and spotted black and white. From throat to vent their underparts are pale gray with narrow black bars; the gray becomes somewhat buffy to the rear. Juveniles are duller overall, have fine black scaling on the crown, and the underparts' black bars are not as crisp.

Distribution and habitat

The riverside wren is found along the Pacific slope from Costa Rica's Gulf of Nicoya into western Panama. It inhabits dense vegetation, preferably along watercourses, swampy edges of woodlands, or on steep precipices. In elevation it ranges from sea level to .

Behavior

Feeding

The riverside wren forages near the ground, usually in pairs or family groups. It sometimes briefly joins other species at army ant swarms. Its diet includes insects and other invertebrates.

Breeding

The riverside wren appears to nest at almost any time of the year. Its nest is globular made of fine fibers; it drapes over a branch to form two chambers with an entrance hole in the outer one. It is often placed over flowing water, above it or the ground. The species also constructs "dormitory" nests for roosting. The clutch size is two.

Vocalization

Both sexes of riverside wren sing, repeated "loud ringing phrases" and followed by different phrases, also repeated. Their calls include "harsh churr and various clear tinkling notes".

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 ...

has assessed the riverside wren as being of Least Concern. However, its "population trend is difficult to determine because of uncertainty over the impacts of habitat modification on population sizes."