The masked gnatcatcher (''Polioptila dumicola'') is a small

songbird A songbird is a bird belonging to the suborder Passeri of the perching birds (Passeriformes). Another name that is sometimes seen as the scientific or vernacular name is Oscines, from Latin ''oscen'', "songbird". The Passeriformes contains 5,00 ...

in the family Polioptilidae. It is found in

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

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 ...

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

Paraguay Paraguay, officially the Republic of Paraguay, is a landlocked country in South America. It is bordered by Argentina to the Argentina–Paraguay border, south and southwest, Brazil to the Brazil–Paraguay border, east and northeast, and Boli ...

, and

Uruguay Uruguay, officially the Oriental Republic of Uruguay, is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast, while bordering the Río de la Plata to the south and the A ...

Taxonomy and systematics

The masked gnatcatcher has three recognized subspecies, the nominate ''Polioptila dumicola dumicola'', ''P. d. saturata'', and ''P. d. berlepschi''. The last subspecies differs in both plumage and voice from the other two and may represent a separate species.Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 23 May 2021. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved May 24, 2021Atwood, J. L. and S. B. Lerman (2020). Masked Gnatcatcher (''Polioptila dumicola''), 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.masgna1.01 retrieved May 29, 2021

Description

The masked gnatcatcher is long and weighs , larger than most other gnatcatchers. The nominate male has a large black mask with a thin white line below it. Its forehead, crown, nape, and upperparts are blue-gray. Its tail is mostly black with white outer feathers. Its throat is pale gray fading to whitish on the belly. The nominate female does not have a mask but instead a black crescent down from the eye. Its upperparts are duller and not as bluish. ''P. d. saturata'' is darker than the nominate; it is slate gray overall that is lighter on the underside. The ''P. d. berlepschi'' male is paler than the nominate, dull gray rather than blue-gray above and white below, and has a narrower mask. The female ''berlepschi'' is paler than the nominate female.

Distribution and habitat

The nominate masked gnatcatcher is found from Paraguay and southern Brazil south into Uruguay and eastern Argentina. It may also be in southeastern Bolivia. ''P. d. saturata'' is found in the Bolivian highlands south of

Cochabamba Department Cochabamba (, , ), from Quechua ''qucha'' or ''qhucha'', meaning "lake", ''pampa'' meaning "plain", is one of the nine departments of Bolivia. It is known to be the " granary" of the country because of its variety of agricultural products from ...

. ''P. d. berlepschi'' is found in central Brazil as far north as

Mato Grosso Mato Grosso ( – ) is one of the states of Brazil, the List of Brazilian states by area, third largest by area, located in the Central-West Region, Brazil, Central-West region. The state has 1.66% of the Brazilian population and is responsible ...

and Amazonas and probably eastern Bolivia. The nominate masked gnatcatcher has been recorded most often in the

Gran Chaco The Gran Chaco or simply Chaco is a sparsely populated, hot and semiarid lowland tropical dry broadleaf forest natural region of the Río de la Plata basin, divided among eastern Bolivia, western Paraguay, northern Argentina, and a portion o ...

biome but also in

Humid Chaco The Humid Chaco ( Spanish: ''Chaco Húmedo'' or ''Chaco Oriental'') is a tropical grasslands, savannas, and shrublands ecoregion in South America. It lies in the basin of the Paraná River, covering portions of central Paraguay and northern Arge ...

and several types of

savanna A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) biome and ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach th ...

, usually at elevations less than . ''P. d. saturata'' inhabits dry

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

between , among the highest habitat for any gnatcatcher. ''P. d. berlepschi'' inhabits

Cerrado The Cerrado () is a vast ecoregion of Tropics, tropical savanna in central Brazil, being present in the states of Goiás, Mato Grosso do Sul, Mato Grosso, Tocantins, Maranhão, Piauí, Bahia, Minas Gerais, São Paulo (state), São Paulo, Paraná ...

and

Pantanal The Pantanal () is a natural region encompassing the world's largest tropical wetland area, and the world's largest Flooded grasslands and savannas, flooded grasslands. It is located mostly within the Brazilian state of Mato Grosso do Sul, but i ...

ecoregions with their widely spaced trees rather than continuous canopy.

Behavior

Feeding

The masked gnatcatcher's diet is small

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 ...

s. It forages in the canopy, most often by gleaning while hopping on branches; it also hover-gleans and sallies for flying prey. It hunts singly and in pairs, most often as part of a

mixed-species foraging flock A mixed-species feeding flock, also termed a mixed-species foraging flock, mixed hunting party or informally bird wave, is a flock (birds), flock of usually insectivorous birds of different species that join each other and move together while fora ...

Breeding

Only the nominate masked gnatcatcher has been studied. Its breeding season spans from September to January. Its nest is a small deep cup made of plant fibers cemented with spider silk and camouflaged by lichens stuck to the outer surface. The clutch is normally three but can be as high as five eggs; both sexes incubate and feed young. Shiny cowbirds (''Molothrus bonariensis'') sometimes parasitize the nest.

Vocalization

The nominate masked gnatcatcher's loudsong is "variable, short, sweet and musical

''P. d. berlepschi''s loudsong is quite different

The species also has a variety of call

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 masked gnatcatcher overall as being of Least Concern. The nominate and ''berlepschi'' appear not to be seriously threatened but ''saturata'' " is considered to be at serious risk due to human settlement and agricultural conversion."

References

{{Taxonbar, from=Q902015 masked gnatcatcher Birds of South America Birds of Argentina Birds of Uruguay Birds of Paraguay Birds of Bolivia Birds of the Cerrado Birds of the Pantanal Birds of the South Region masked gnatcatcher Taxa named by Louis Pierre Vieillot Taxonomy articles created by Polbot