Horned Curassow (Pauxi unicornis)

Image of a Horned Curassow in its natural habitat

Introduction

The Horned Curassow (Pauxi unicornis) is a large, ground-dwelling member of the curassow family, Cracidae. It is endemic to Bolivia, where it inhabits humid forest on the eastern Andean slopes. Some older classifications included the isolated Peruvian Sira population within this species, but that population is now generally treated as the separate Sira Curassow (Pauxi koepckeae). (birdsofbolivia.org)

Physical Description

The Horned Curassow is approximately 85–90 cm long and has a heavy, upright build suited to life on the forest floor. Its plumage is predominantly black with a metallic blue-green gloss across the upperparts and breast. The lower belly and vent are creamy white, and the tail has broad white tips.

Its most distinctive feature is a tall, laterally compressed, leaden-blue casque rising vertically from the base of the upper mandible. The casque can be approximately 5–6 cm long. The bill is bright red, while the legs are greyish to dull yellow-orange, with colour variation reported during the breeding season. Females are broadly similar to males, although a rufous colour phase has been reported. (birdsofbolivia.org)

Range and Habitat

The Horned Curassow is endemic to Bolivia. Its known range lies in the lower Yungas and Andean foothills, especially in the departments of Cochabamba and Santa Cruz. It occupies dense, humid lower-montane and adjacent evergreen forest, generally between about 400 and 1,200 metres above sea level, with occasional records at higher elevations.

The species is not migratory. Its distribution is naturally restricted and fragmented, and it is associated with forested areas that retain substantial cover and relatively little disturbance. Important protected areas within or near its known range include Amboró National Park, Carrasco National Park and Isiboro-Sécure National Park. (birdsofbolivia.org)

Behaviour and Diet

Horned Curassows spend much of their time on the ground, where they walk through dense vegetation in search of food. Their diet includes fruits, seeds and nuts, with additional records of soft plant material, larvae and insects. They may also probe or dig in the leaf litter while foraging.

The species is secretive and difficult to observe. During the breeding season, males produce a deep booming song that can carry through the forest. The Bolivian form has a sequence of several phrases lasting approximately 8–10 seconds, followed by a distinctive loud final note. This vocal activity is useful for surveys because visual encounters are uncommon. (cambridge.org)

Breeding information remains limited. A nest studied in Amboró National Park was attended by a female, which incubated alone, left the nest at night and returned at first light. The clutch is thought to be small, probably about two eggs, based partly on information from related curassows, but detailed information on incubation, chick development and parental care is still incomplete. Claims that both parents routinely incubate and rear the young are not sufficiently documented for this species. (cambridge.org)

Identification Tips

Look for the following combination of features:

A large, heavy-bodied black curassow in humid Andean foothill forest.
A conspicuous vertical, blue-grey casque above the red bill.
Creamy-white lower belly and vent.
Broad white tips on the tail feathers.
Greyish to dull yellow-orange legs.
A deep, far-carrying booming song during the breeding season.

The tall, relatively narrow casque and the white tail markings help distinguish the Horned Curassow from the Sira Curassow, which is now generally treated as a separate species and occurs in Peru. The Sira Curassow has a smaller casque and lacks the white markings on the tips of the central tail feathers. In areas where other large curassows occur, identification by voice may be difficult, so the complete song sequence and casque shape should be considered together. (eprints.gla.ac.uk)

Conservation Status

The Horned Curassow is listed as Endangered in the IUCN Red List assessment published in 2025.2. Older assessments listed it as Critically Endangered, so historical sources may show a different category. The change reflects improved assessment of the available distribution and population evidence, not the disappearance of the threats facing the species. (nc.iucnredlist.org)

The population is considered to be declining. The principal threats are hunting and the loss, degradation and fragmentation of humid forest through agricultural expansion, road building, settlement and other infrastructure development. Its restricted distribution and dependence on dense forest increase its vulnerability to local declines.

Conservation priorities include protecting remaining forest in the species’ known range, maintaining effective management of national parks and Indigenous territories, reducing hunting pressure, improving community participation and carrying out systematic surveys. Further research is also needed to clarify population size, distribution, breeding ecology and the effectiveness of conservation actions. (forums.birdlife.org)

Frequently Asked Questions

Where does the Horned Curassow live?

The Horned Curassow is endemic to Bolivia. It occurs mainly in humid lower-montane and evergreen forests on the eastern slopes and foothills of the Andes, particularly in Cochabamba and Santa Cruz departments.

How large is a Horned Curassow?

Adults are approximately 85–90 cm long. The species is a large, heavy-bodied forest bird with a prominent blue-grey casque above its red bill.

What does the Horned Curassow eat?

It feeds mainly on fruits, seeds and nuts. It also takes other plant material and some invertebrates, including larvae and insects, while foraging on or near the forest floor.

Why is the Horned Curassow endangered?

The main threats are hunting and the destruction or fragmentation of humid forest. Its small, restricted range means that local losses can have a significant effect on the species as a whole.

Is the Sira Curassow the same species?

No. Older classifications treated the Peruvian Sira population as a subspecies of the Horned Curassow, Pauxi unicornis koepckeae. Current treatments generally recognise it as the separate Sira Curassow, Pauxi koepckeae.

References

BirdLife International. 2025. Horned Curassow (Pauxi unicornis), 2025.2 Global Threatened Bird Forums assessment. BirdLife International. Available at: https://forums.birdlife.org/2025-2-horned-curassow-pauxi-unicornis/ (accessed 8 September 2026).
BirdLife International. 2025. IUCN Red List of Threatened Species 2025.2: Pauxi unicornis. IUCN Red List category statistics, Table 7. IUCN Red List of Threatened Species. Available at: https://nc.iucnredlist.org/redlist/content/attachment_files/2025-2_RL_Table7.pdf (accessed 8 September 2026).
Cox, G., Read, J. M., Clarke, R. O. S. & Easty, V. S. 1997. Studies of Horned Curassow Pauxi unicornis in Bolivia. Bird Conservation International, 7(3), 199–211. https://doi.org/10.1017/S0959270900001532
Corvacho, M. G., MacLeod, R., Brooks, D. & Hennessey, B. 2011. Distinctive morphology, ecology, and first vocal descriptions of Sira Curassow (Pauxi [unicornis] koepckeae): evidence for species rank. Ornitologia Neotropical, 22(2), 267–279. University of Glasgow repository: https://eprints.gla.ac.uk/62571/ (accessed 8 September 2026).
García-Solíz, V. H., Soria-Auza, R., Bruckner, C. M. & Herzog, S. K. 2007. Plan de acción preliminar para la conservación de Pauxi unicornis en Bolivia. Asociación Armonía and BirdLife International, Santa Cruz de la Sierra, Bolivia.
Gill, F., Donsker, D. & Rasmussen, P. (eds). 2026. IOC World Bird List, version 15.2. International Ornithologists’ Union. Available at: https://www.worldbirdnames.org/new/ioc-lists/ (accessed 8 September 2026).
U.S. Fish and Wildlife Service. 2024. Endangered and Threatened Wildlife and Plants: Endangered Species Status for Sira Curassow and Southern Helmeted Curassow. Federal Register, 89, 60319–60335. Available at: https://www.fws.gov/species-publication-action/endangered-and-threatened-wildlife-and-plants-endangered-species-133 (accessed 8 September 2026).
Birds of Bolivia. 2019. Pauxi unicornis, Horned Curassow species account. Available at: https://birdsofbolivia.org/species-fact-sheets-2/guans-and-chachalacas-pavas-y-afines/pauxi-unicornis/ (accessed 8 September 2026).