Sooty tyrannulet  (Serpophaga nigricans)

Classified as Least Concern (LC) on the IUCN Red List (1).

First described by Charles Darwin during his voyage on the H.M.S. Beagle (3), the sooty tyrannulet is a small, uniform grey to brownish-grey bird with a contrasting black tail. The underparts are paler grey, while the wings have two indistinct grey bars, and pale edges on the flight feathers. The chin is whitish and the top of the head bears a white patch, which is usually partially concealed (2) (4). The legs and the small beak are black. Male and female sooty tyrannulets are similar in appearance. The song has been described as a few staccato notes followed by higher, sweet, ‘canary-like’ notes (2).

The sooty tyrannulet is found in South America, in southern Bolivia, Paraguay, southeast Brazil, Uruguay, and northern and central Argentina, at elevations of up to 1,000 metres. Although usually resident, populations in the extreme south may migrate northwards in winter (2) (4).

This species is almost always found near water, occurring in brush, shrubs, and along rocky streams and river margins. It can also be found along irrigation ditches, farm ponds, in agricultural areas and pastures with standing water, and around farmyards (2) (4).

The sooty tyrannulet is an active and restless bird, constantly on the move as it flits from perch to perch, or darts into the air, to the ground or to the water surface to catch insects (2) (4). It may also land on floating vegetation or on rocks or logs in the middle of the water (4). When perched, the tail is regularly pumped up and down, and is often fanned out (2) (3) (4).

The sooty tyrannulet is usually found in pairs (4). Breeding takes places between October and December, with both the male and female helping to build the nest, which is a tightly woven open cup or basket. The nest may be suspended from a branch, twig or root, often under an overhang, and is constructed from roots and grasses, and lined with feathers. Three eggs are usually laid. Nests may occasionally be targeted by the shiny cowbird (Molothrus bonariensis), a brood parasite (2).

The sooty tyrannulet is not currently considered at risk of extinction, as it has a large distribution, and a relatively large and stable population (5). Its tolerance of altered habitats also helps to reduce the threats to this species (2).

The sooty tyrannulet occurs in a number of national parks and other protected areas throughout its range, including Ybycuí National Park in Paraguay, Aparados da Serra, Iguaçu and Serra da Canastra National Parks in Brazil, and Iguazú National Park and San Juan de Poriahú Private Reserve in Argentina (2). There are no known specific conservation measures in place for this species.

View information on this species at the UNEP World Conservation Monitoring Centre.

To find out more about the sooty tyrannulet see:

• BirdLife International:
  http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=4162&m=0
• del Hoyo, J., Elliott, A. and Sargatal, J. (2004) Handbook of the Birds of the World. Volume 9: Cotingas to Pipits and Wagtails. Lynx Edicions, Barcelona.