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

Records from Área Natural Protegida Península Valdés

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




 View all photographs of the species




 Add a photography of this species





Last Vocalizations published



Audio playerUserDateCountryProvincePlaceSexLife stageIt was observedDetails
Santiago Sainz-trápaga04/29/2014ArgentinaChubutPunta DelgadaÁrea Natural Protegida Península ValdésIndistinguishableJuvenileYesNo



 See all the audios of the species




 Add an audio of this species





Last Filmings published





 Ver todos los videos de la especie




 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
243818415/02/2026ArgentinaChubutÁrea Natural Protegida Península ValdésDolores Fernandez
220536230/10/2024ArgentinaChubutÁrea Natural Protegida Península ValdésPatricia Gabriela Mancilla Iglesias
218867422/10/2024ArgentinaChubutCaminos internos de la península, Área Natural Protegida Península ValdésEduardo Cusano
218351922/10/2024ArgentinaChubutCaminos internos de la península, Área Natural Protegida Península ValdésSergio Cusano
215782023/09/2024ArgentinaChubutCaleta Valdés, Área Natural Protegida Península ValdésPablo Marcelo Meyer
202279805/04/2024ArgentinaChubutPunta Norte, Área Natural Protegida Península ValdésPablo Marcelo Meyer
202398804/04/2024ArgentinaChubutPunta Norte, Área Natural Protegida Península ValdésPablo Marcelo Meyer
201912531/03/2024ArgentinaChubutPunta Norte, Área Natural Protegida Península ValdésNicolas Olejnik
201897230/03/2024ArgentinaChubutPunta Norte, Área Natural Protegida Península ValdésNicolas Olejnik
201775001/03/2024ArgentinaChubutPunta Norte, Área Natural Protegida Península ValdésNicolas Olejnik
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 12/03/2026.