Introduction
The Plain-tailed Nighthawk (Nyctiprogne vielliardi) is a small nightjar in the family Caprimulgidae. Endemic to Brazil, it is associated mainly with riverine habitats in the São Francisco River valley of Bahia and Minas Gerais. The species was described in 1994 and was originally placed in the genus Chordeiles, but subsequent morphological, vocal and ecological evidence supported its transfer to Nyctiprogne.
Physical Description
The Plain-tailed Nighthawk is a small nightjar, measuring about 19 cm in length. Its plumage is cryptic, with brown, grey and buff tones that provide camouflage among dense vegetation and river-margin cover. The wings are largely unmarked, and the tail lacks the conspicuous white median band found in the closely related Band-tailed Nighthawk (Nyctiprogne leucopyga).
The species has a short bill and the compact structure typical of Nyctiprogne. Available information is based on relatively few specimens and field observations, so details of sexual dimorphism, age-related plumage variation and individual variation remain poorly documented.
Range and Habitat
The Plain-tailed Nighthawk is endemic to Brazil. Known records are concentrated along the São Francisco River and nearby tributaries in Bahia and northern Minas Gerais, although it may occur more widely along suitable sections of the river system.
It is most closely associated with gallery woodland, brushy river margins and other dense vegetation beside water. This habitat preference distinguishes it from the Least Nighthawk (Chordeiles pusillus), which more often uses seasonally dry or open habitats and may occur farther from rivers. The species is not best characterised as a bird of undifferentiated Cerrado or open Caatinga, because available observations indicate a stronger association with wooded and brushy river edges.
The Plain-tailed Nighthawk is considered resident within its known range. Its distribution is restricted and fragmented by the loss and degradation of riverine vegetation.
Behaviour and Diet
The species is crepuscular and probably nocturnal. It usually begins foraging around dusk, flying low over rivers and adjacent vegetation while capturing insects in the air. Its flight has been described as shallow and fluttering, with brief glides between wingbeats.
During daylight, individuals roost in dense, often brushy vegetation rather than habitually resting on exposed ground. Birds may roost in loose groups, with observations of several individuals using nearby low perches. When disturbed, they can give short single or double notes. Vocalisations and flight activity have also been recorded from day-roost areas.
Breeding information is limited. As with other nightjars, the species is expected to lay its eggs on or close to the ground without constructing a substantial nest, but detailed information on nesting sites, clutch size, incubation and parental care should be treated as insufficiently documented for this species.
Identification Tips
- Look for a small, compact nightjar flying low over a river or wooded river margin at dusk.
- The combination of unmarked wings and a plain tail is distinctive within its local nightjar community.
- Unlike the Band-tailed Nighthawk, the Plain-tailed Nighthawk lacks the latter’s conspicuous white median tail-band and prominent white lateral throat patches.
- Its preference for gallery woodland, brushy river edges and watercourses helps separate it from the more open-country Least Nighthawk.
- Identification is often easiest at dusk, when the birds may forage in small groups above the water. Calls and flight behaviour can provide useful supporting evidence, but the species remains difficult to detect and study.
Conservation Status
The Plain-tailed Nighthawk is currently assessed as Near Threatened on the IUCN Red List. The assessment reflects its restricted distribution and the continuing degradation of suitable riverine habitat. No reliable population estimate should be given because the species remains poorly known.
The principal conservation concerns are the clearance and fragmentation of gallery woodland and brush along the São Francisco River and its tributaries, together with wider agricultural, urban and other land-use pressures. Conservation priorities include protecting remaining riverine vegetation, maintaining habitat connectivity, surveying poorly known sections of the species’ range and improving knowledge of its population, breeding ecology and habitat requirements.
Frequently Asked Questions
Where does the Plain-tailed Nighthawk live?
It is endemic to Brazil and is known mainly from riverine habitats along the São Francisco River and nearby tributaries in Bahia and Minas Gerais.
Is the Plain-tailed Nighthawk migratory?
It is generally treated as resident within its Brazilian range. There is no well-established evidence of regular long-distance migration.
What does the Plain-tailed Nighthawk eat?
It feeds on flying insects captured in the air, usually while foraging at dusk or during the night over rivers and adjacent vegetation.
How can the species be identified in the field?
The most useful clues are its small size, low flight over water, largely unmarked wings and plain tail without the white median band of the Band-tailed Nighthawk.
Does the Plain-tailed Nighthawk build a nest?
Detailed breeding information is scarce. It is expected to lay its eggs directly on or near the ground, as is typical of many nightjars, but species-specific nesting details remain poorly documented.
Is the Plain-tailed Nighthawk threatened?
Yes. It is assessed as Near Threatened because of its restricted range and the loss and degradation of riverine woodland and brush within that range.
References
- BirdLife International. n.d. “Bahian Nighthawk Nyctiprogne vielliardi Species Factsheet.” BirdLife DataZone. Accessed 8 September 2026. https://datazone.birdlife.org/species/factsheet/bahian-nighthawk-nyctiprogne-vielliardi
- Cleere, N. 2004. “A Previously Unidentified Museum Specimen of Plain-tailed Nighthawk Nyctiprogne vielliardi (Caprimulgidae).” Bulletin of the British Ornithologists’ Club 124(1).
- Gill, F., D. Donsker and P. Rasmussen, eds. 2026. IOC World Bird List, version 15.2. International Ornithologists’ Union. Accessed 8 September 2026. https://www.worldbirdnames.org/
- Lencioni-Neto, F. 1994. “Une nouvelle espèce de Chordeiles (Aves, Caprimulgidae) de Bahia (Brésil).” Alauda 62: 242–245.
- South American Classification Committee. 2006. “Reassign Chordeiles vielliardi to Genus Nyctiprogne.” Proposal 232, American Ornithologists’ Society, hosted by the Louisiana State University Museum of Natural Science. Accessed 8 September 2026. https://www.museum.lsu.edu/~Remsen/SACCprop232.htm
- Whitney, B. M., J. F. Pacheco, P. S. M. Fonseca, R. E. Webster, G. M. Kirwan and J. M. Barnett. 2003. “Reassignment of Chordeiles vielliardi Lencioni-Neto, 1994, to Nyctiprogne Bonaparte, 1857, with Comments on the Latter Genus and Some Presumably Related Chordeilines (Caprimulgidae).” Bulletin of the British Ornithologists’ Club 123(2): 103–112.
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