Don't want to see ads? Sign up...




Species icon
Variable Hawk

Geranoaetus polyosoma
(Quoy, JRC; Gaimard, JP, 1824)
Aguilucho Común
Gavião-de-costas-vermelhas

Family: Accipitridae
Order: Accipitriformes
Class: Aves
Phylum / Division: Chordata
Kingdom: Animalia

 Request change
Filters


Conservation status according to BirdLife International: Least Concern

Other common names: Ñanco, Aguilucho Variable.

Synonyms: Buteo polyosoma, Falco polyosoma.

Subspecies:


Description: It is a large, long-winged raptor with a slender profile and remarkable plumage variability. Individuals range from mostly ash-gray to rufous or chestnut tones, with lighter or darker underparts depending on morph. In flight, it is recognized by its slightly raised wings forming a shallow “V”, relatively short tail, and pale patches at the base of the primaries. Juveniles tend to be browner and more streaked.

Geographic distribution: It is widely distributed across South America, from southern Colombia and Venezuela to southernmost Chile and Argentina. It is especially common along the Andes, but also inhabits Patagonian steppes, intermontane valleys, and open lowlands.

Habitat: It occupies open and semi-open habitats, including grasslands, shrublands, agricultural areas, and mountainous regions. It tolerates a broad altitudinal range, from sea level to over 4,000 m, efficiently using thermal currents for soaring.

Diet: It is an opportunistic predator, feeding mainly on small mammals (particularly rodents), medium-sized birds, reptiles, and large insects. It also scavenges when opportunities arise, which increases its dietary flexibility.

Behavior: Usually seen alone or in pairs, though it may gather where food is abundant. It spends long periods soaring with a powerful yet economical flight, and maintains large territories during the breeding season.

Nesting: It builds large stick nests, typically on rocky cliffs, escarpments, or occasionally tall trees and human-made structures. Clutches usually consist of one to two eggs, with shared parental care and an extended fledging period.

Conservation status: It is classified as Least Concern globally due to its wide range and generally stable populations, although local threats include persecution, electrocution, and habitat alteration.


Author of this compilation: EcoRegistros – 15/12/2025




Loading map...




Last published photographs

Foto
Photography ID: 367370
  Adult

Camino a La Carrera
Mendoza
Argentina
07/08/2019
Max Uranga
Foto
Photography ID: 315728
  Fledgling

Laguna del Diamante
Mendoza
Argentina
01/14/2019
Max Uranga
Foto
Photography ID: 315266
 
Laguna del Diamante
Mendoza
Argentina
01/10/2019
Max Uranga
Foto
Photography ID: 315265
  Adult

Laguna del Diamante
Mendoza
Argentina
01/10/2019
Max Uranga
Foto
Photography ID: 307739
  Adult

Manzano Historico
Mendoza
Argentina
12/08/2018
Max Uranga
Foto
Photography ID: 292478
  Adult

Malargüe
Mendoza
Argentina
08/18/2018
Max Uranga
Foto
Photography ID: 292477
  Adult

Malargüe
Mendoza
Argentina
08/18/2018
Max Uranga
Foto
Photography ID: 292476
  Adult

Malargüe
Mendoza
Argentina
08/18/2018
Max Uranga
Foto
Photography ID: 291825
  Adult

San Carlos
Mendoza
Argentina
08/16/2018
Max Uranga
Foto
Photography ID: 218577
  Juvenile

El Infiernillo
Tucumán
Argentina
07/13/2017
Max Uranga
Foto
Photography ID: 218399
  Juvenile

Parque Nacional El Leoncito
San Juan
Argentina
01/29/2017
Max Uranga
Foto
Photography ID: 183560
  Immature

San Martin de los Andes
Neuquén
Argentina
08/06/2016
Max Uranga



 View all photographs of the species




 Add a photography of this species





Last Vocalizations published




 Add an audio of this species





Last Filmings published




 Add a film of this species





 Reports


 Detail of places sorted by number of records








Page 1
Record IDDateExact timeCountryProvince / departmentPlaceFilmedPhotographedRecorded vocalObservedHeardWounded or deadNumber of individualsUser or BibliographyDetail
114607108/07/2019ArgentinaMendozaCamino a La CarreraMax Uranga
88451814/01/2019ArgentinaMendozaLaguna del DiamanteMax Uranga
88333610/01/2019ArgentinaMendozaLaguna del DiamanteMax Uranga
86122908/12/2018ArgentinaMendozaCamino que sube a la cordillera y cruza a chile, Manzano HistoricoMax Uranga
82172118/08/2018ArgentinaMendozaValle de las Leñas, MalargüeMax Uranga
81915516/08/2018ArgentinaMendozaFinca el remanso, San CarlosMax Uranga
61323213/07/2017ArgentinaTucumánDe Tafí a Amaicha, El InfiernilloMax Uranga
61289529/01/2017ArgentinaSan JuanParque Nacional El LeoncitoMax Uranga
49368106/08/2016ArgentinaNeuquénSan Martin de los Andes, San Martin de los AndesMax Uranga
47713714/06/2016ArgentinaMendozaTupungatoMax Uranga
Page 1

 Add a record of this species

Citation recommended:

EcoRegistros. 2026. Variable Hawk (Geranoaetus polyosoma) - Species sheet. Acceded from https://www.ecoregistros.org on 05/04/2026.