Black capped Donacobius (Donacobius atricapilla)

[order] Passeriformes | [family] Troglodytidae | [latin] Donacobius atricapilla | [UK] Black-capped Donacobius | [FR] Troglodyte a miroir | [DE] Rohrspotter | [ES] Ratona de Capa Negra | [IT] Scricciolo mimo | [NL] Zwartkap-donacobius

Subspecies

Physical charateristics

The black-capped donacobius wren averages in length from 21 to 22 centimeters. It is unmistakable with a head and shoulders that are glossy black, a back that is more of a brown, and a rump that is olive-brown. Its tail feathers are black with noticeable white tips. Its wings are blackish with an obvious white flash at the bottom. The bird has underparts that are a warm yellow with black bars on its side. Its eyes are a bright yellow, and its legs are a dusky green. The black-capped donacobius also has a yellow cheek pouch that can puff out.

Listen to the sound of Black-capped Donacobius

[audio:http://www.aviflevoland.nl/sounddb/B/Black-capped Donacobius.mp3]

Copyright remark: Most sounds derived from xeno-canto

Range

It is found in tropical swamps and wetlands in Argentina, Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Paraguay, Peru, Suriname, and Venezuela; also Panama of Central America.

Habitat

Black-capped Donacobius are common in a wide range of Amazonian wetlands, including oxbow lakes, riparian zones, and other areas with tall dense aquatic or semi-aquatic vegetation.

Reproduction

Donacobius nest is built in vegetation, reeds or grass, often over standing water, at about 25 cm to 1 meter above water. But nest may be built in other places, and when it is not over water, nest is located higher, up to 2 meter above the ground. The nest is mainly built by female. It is a bulky open cup (external sizes 10 to 15 cm) with a nesting cup of 6cm depth and 8 cm in diameter. Nest is made with grass, plant fibres, and other materials frequently added, such as snake skins and silk from spider webs and cocoons. Donacobius may also take some materials from nests of other species. Breeding occurs during rainy months.
Female lays 2 purplish-white eggs, heavily spotted with reddish and purplish. Incubation lasts about 16 to 18 days, by female alone. Altricial chicks are naked at hatching. Adults wet them with their own soaked feathers, after immersion into the water. Young are fed by both parents, but also by helpers which are offspring from the last breeding season, or for one or two seasons before. Young fledge when they are 17 to 18 days old. When nesting care is shared by pair and helpers, broods are more productive. Helpers assist breeding pair in defence of the territory, feeding young and guarding the nest. This species seems to produce one single brood and a second clutch of replacement if the first is lost. But sometimes, pair may produce two broods per year.

Feeding habits

Donacobius feeds mainly on invertebrates. It gleans from leaf surface in grass, and may also catch flying insects, from low perches over water. It forages in vegetation and grassy marshes where it probes and plugs insects. Donacobius is probably entirely resident in its range. Pairs live in narrow territories along water edges. A large portion consists of marshy edges. Both display and sing duets at the boundaries. Group members forage close to each other, within a few metres. But if other Donacobius from other group enter their area, or at territory boundaries, they strongly display and call against intruders. Territorial displays are frequent during one to two hours after dawn. Pairs are perched near a common boundary, and alternate duets against each other. We can hear a grating scold, uttered by either sex. It is an answer to the disturbance or at predator. During the strong calling bouts, the orange-yellow throat pouches are inflated and puffed out laterally, and especially that of the male. Family members may join the pair in these displays. These types of aggression or displays may occur when the groups meet in feeding areas.

Conservation

This species has a large range, with an estimated global extent of occurrence of 8,700,000 km². The global population size has not been quantified, but it is believed to be large as the species is described as ‘common’ in at least parts of its range (Stotz et al. 1996). Global population trends have not been quantified, but the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e., declining more than 30% in ten years or three generations). For these reasons, the species is evaluated as Least Concern.

Migration

Sedentary throughout range.

Distribution map

Literature

Title A family name for the monotypic oscine passerine genus Donacobius

Author(s): Alexandre Aleixo and José Fernando Pacheco

Abstract: The taxonomic affinities of the Neotropical endemi..[more]..

Source: Revista Brasileira de Ornitologia 14 (2) 172-173

Title THE NESTING OF SOME VENEZUELAN BIRDS

Author(s): ALEXANDER F. SKUTCH

Abstract: I passed the interval from 15 March to 24 July 196..[more]..

Source: The Condor(70,1): 66-82

Title REPRODUCTION AND SOCIAL ORGANIZATION OF THE BLACK-CAPPED DONACOBIUS (DONACOBIUS TRICAPILLUS) IN SOUTHEASTERN PERU

Author(s): RICHARD A. KILTIE AND JOHN W. FITZPATRICK

Abstract: A color-banded population of Black-capped Donacobi..[more]..

Source: The Auk 101: 804-811