The chestnut-collared swift (''Streptoprocne rutila'') 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 lightweig ...

in subfamily

Cypseloidinae The Cypseloidinae are a subfamily of swifts and contain the following species: * Genus ''Cypseloides'' :* Spot-fronted swift (''Cypseloides cherriei'') :* White-chinned swift (''Cypseloides cryptus'') :* Sooty swift (''Cypseloides fumigatus'' ...

of the swift family

Apodidae The swifts are a family, Apodidae, of highly aerial birds. They are superficially similar to swallows, but are not closely related to any passerine species. Swifts are placed in the order Apodiformes with hummingbirds. The treeswifts are closely ...

. It is found from

Mexico Mexico ( Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guate ...

and

Trinidad Trinidad is the larger and more populous of the two major islands of Trinidad and Tobago. The island lies off the northeastern coast of Venezuela and sits on the continental shelf of South America. It is often referred to as the southernmos ...

south to

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and

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.HBW and BirdLife International (2021) Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world. Version 6. Available at: http://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v6_Dec21.zip retrieved August 7, 2022

Taxonomy and systematics

The chestnut-collared swift has at various times been placed in genera ''Cypseloides'' and ''Chaetura''. These three subspecies are recognized: *''S. r. griseifrons'' (

Nelson Nelson may refer to: Arts and entertainment * ''Nelson'' (1918 film), a historical film directed by Maurice Elvey * ''Nelson'' (1926 film), a historical film directed by Walter Summers * ''Nelson'' (opera), an opera by Lennox Berkeley to a lib ...

, 1900) *''S. r. brunnitorques'' ( Lafresnaye, 1844) *''S. r. rutila'' (

Vieillot Louis Pierre Vieillot (10 May 1748, Yvetot – 24 August 1830, Sotteville-lès-Rouen) was a French ornithologist. Vieillot is the author of the first scientific descriptions and Linnaean names of a number of birds, including species he collecte ...

, 1817) Subspecies ''S. r. brunnitorques'' has been treated as a separate species, but it is now (2020) suspected of not being even a separate subspecies, as "no clear diagnosis of distinctions between brunnitorques and rutila has been published."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 24 July 2022. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved July 24, 2022Schulenberg, T. S. and C. Shaw (2020). Chestnut-collared Swift (''Streptoprocne rutila''), version 1.0. In Birds of the World (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.chcswi1.01 retrieved October 2, 2022

Description

The chesnut-collared swift is one of the smaller members of genus ''Streptoprocne''. It is long and weighs about . It has a wide slightly notched tail and broad wings. Adult males of the

nominate subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics ( morphology), but that can successfully interbreed. Not all spec ...

''S. r. rutila'' have a sooty blackish brown crown, a blackish brown back, slightly paler rump and uppertail

coverts A covert feather or tectrix on a bird is one of a set of feathers, called coverts (or ''tectrices''), which, as the name implies, cover other feathers. The coverts help to smooth airflow over the wings and tail. Ear coverts The ear coverts are s ...

, and a sooty blackish brown tail. They have a narrow black patch around the eye and grayish brown cheeks, chin, and throat with some dull rufous feathers mixed in. They have a wide rufous collar across the lower throat and upper breast that extends around to the nape. The upper side of their wing is shades of black and the underside slightly lighter. Their underparts are a paler blackish brown than the upperparts. Adult females have paler body plumage than males and have a much smaller rufous collar or none at all. Juveniles resemble adult females but are paler overall. Subspecies ''S. r. griseifrons'' has sooty gray rather than almost black upperparts, sooty grayish brown underparts, and pale gray fringes on most facial feathers. Subspecies ''S. r. brunnitorques'' is essentially indistinguishable from the nominate.

Distribution and habitat

The subspecies of chestnut-collared swift are distributed thus: *''S. r. griseifrons'', western Mexico from

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Durango Durango (), officially named Estado Libre y Soberano de Durango ( en, Free and Sovereign State of Durango; Tepehuán: ''Korian''; Nahuatl: ''Tepēhuahcān''), is one of the 31 states which make up the 32 Federal Entities of Mexico, situated i ...

and

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south to

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*''S. r. brunnitorques'', southeastern Mexico through Central America and along the Andes of Colombia, Ecuador, Bolivia, and Peru *''S. r. rutila'', Andes and Coastal Ranges of Venezuela; Trinidad The exact extent of each range is imperfectly known. Some specimens attributed to ''S. r. griseifrons'' have been collected in Venezuela and much further south, though few taxonomists agree with those identifications. Other taxonomists extend the range of ''S. r. brunnitorques'' into Venezuela, an area which most assign to ''S. r. rutila'', and some have proposed that ''brunnitorques'' should be merged into ''rutila''. The chestnut-collared swift inhabits a variety of landscapes including humid

montane 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 ...

and pine-oak forests,

semi-deciduous Semi-deciduous or semi-evergreen is a botanical term which refers to plants that lose their foliage for a very short period, when old leaves fall off and new foliage growth is starting. This phenomenon occurs in tropical and sub-tropical woody ...

forest,

evergreen forest An evergreen forest is a forest made up of evergreen trees. They occur across a wide range of climatic zones, and include trees such as conifers and holly in cold climates, eucalyptus, Live oak, acacias, magnolia, and banksia in more temperat ...

, semi-open areas, and small human communities. In elevation it ranges from a few hundred meters above sea level to as high as in Mexico and northern Central America, in Costa Rica and Colombia, in Ecuador, and in Bolivia.

Behavior

Movement

The chestnut-collared swift is a year-round resident throughout its range, though it apparently makes some local seasonal movements.

Feeding

Like all swifts, the chestnut-collared is an aerial insectivore. Details of its diet are lacking but it is known to feed on several families of insects. Some studies have shown a preference for flying ants and others for small beetles; their results may represent local or temporal availability. It often forages in flocks of 10 to 20 birds and sometimes much higher numbers. It sometimes forages with other swift species and tends to stay near the top of such mixed-species flocks.

Breeding

The chestnut-collared swift's breeding season varies with latitude but generally is within May to August north of the equator; the season at and below the equator has not been determined. It builds a nest of mud and plant material such as moss, liverwort, and fern on small ledge or niche of a rock wall in a damp shady location near water, such as in a cave, under a bridge, or in a culvert. The clutch size is two eggs. Both parents incubate the eggs for 22 to 23 days and fledging occurs at five to six weeks after hatch.

Vocalization

One description of the chesnut-collared swift's flight call is "buzzy...like electric crackles or static, occasionally strung into a chatter: ''bzzzz'tzz'tzz'tzz zz zzzz zzzzz zzzz''."

Status

The IUCN has assessed the chestnut-collared swift as being of Least Concern. It has a very large range and an estimated population of at least 50,000 mature individuals, though the latter is believed to be decreasing. No immediate threats have been identified. "Human activity probably has little effect on Chestnut-collared Swift".

References

External links

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