Black-and-chestnut Eagle Spizaetus isidori Scientific name definitions

Tomás Rivas-Fuenzalida, Juan M. Grande, Sebastián Kohn, Felix Hernán Vargas, and Santiago Zuluaga Castañeda
Version: 2.0 — Published November 23, 2022

Conservation and Management

The species has been listed as globally Endangered (C2a(i)) by Birdlife International since 2014, on the basis of its declining population and small population size. The destruction of its montane forest habitat, as well as direct human persecution, are inferred to be driving a rapid and continued population decline (56). This assessment is based on recent observations on abundance parameters in Colombia, the low number of records in extensive areas of Venezuela, southern Bolivia, and northern Argentina, and the growing evidence of persecution throughout its distribution range.

Conservation Status by Country


Near Threatened (59).


Endangered (60).


Critically Endangered (61).


Vulnerable (62).


Vulnerable (63).


Endangered (64).

Effects of Human Activity

Throughout its range, the main threats to the Black-and-chestnut Eagle are habitat loss and human persecution. The feeding habits of this eagle, including a significant proportion of medium-sized birds in its diet, makes it very vulnerable to human persecution because of its predation on poultry (65, 66).

Habitat Loss and Degradation

In Colombia, historical habitat loss was estimated at 60.6% in 2014 (60). This threat is present virtually throughout its entire distribution. In Argentina, montane forests in the Yungas are actually relatively protected by forest conservation laws and protected areas, but have suffered from intensive selective logging for decades and have a high incidence of free ranging cattle that eliminates the understory, compromising the long-term renewal of an already impoverished forest. In addition, 70% of lowland transitional forest that may act as corridors between mountain ranges for the species has already been deforested (67).

Shooting and Trapping

In one study in Colombia, the human perception of Black-and-chestnut Eagles was largely negative, and the researchers obtained evidence that indicated that at least 47 eagles were shot, and 16 were captured (three for illegal trafficking) (51). The persecution occurs in retaliation for, or as a preventive measure against, chicken predation, and is a significant cause of mortality of this species in Colombia, Ecuador, and Peru (51, 54, Rivas-Fuenzalida et al., unpublished data). Human persecution was detected in 54.2% of the known breeding territories in the central Andes of Peru (n = 35), resulting in 25 juveniles, 3 adults, 2 immatures, and 9 unaged eagles to be killed between 1999 and 2020 (Rivas-Fuenzalida et al., unpublished data, Orizano et al., unpublished data). Despite evidence that Black-and-chestnut Eagle preys on domestic chickens in Argentina (37), surveys conducted in the northern half of the species distribution there suggests that the rural population has little knowledge of the species and has no particular conflict with the eagle (68). However, of two GPS-banded dispersing juveniles, one was shot and the other disappeared in the same area (Zuluaga et al., unpublished data).

Collisions with Stationary Structures or Objects

In addition to habitat loss and human persecution, the species has also been documented to have been electrocuted on high-tension wires. In Colombia, two were recorded as being electrocuted (51), while in Ecuador, juveniles from at least two nesting sites were also electrocuted (SK, unpublished data).


In Colombia, Ecuador, Peru, and Argentina, the Black-and-chestnut Eagle Project South America (BCE Project) was developed in 2017 to preserve the known reproductive populations of the species. This project is being driven by several NGOs and research institutes, including Fundación Proyecto Águila Crestada Colombia, Fundación Cóndor Andino Ecuador, Fundación Ñankulafkén, Club de Observadores de Aves de Oxapampa, The Peregrine Fund, and Colaboratorio de Biodiversidad, Ecología y Conservación-CONICET. In this project, the number of known nests of the species in South America increased from 4 (in 2014) to ~50 (in 2022).

Recommended Citation

Rivas-Fuenzalida, T., J. M. Grande, S. Kohn, F. H. Vargas, and S. Zuluaga Castañeda (2022). Black-and-chestnut Eagle (Spizaetus isidori), version 2.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.baceag2.02