Black-and-chestnut Eagle

This is a magnificent and powerful raptor measuring between 24 and 31 inches in length, with an impressive wingspan ranging from 57 to 65 inches. It possesses a robust silhouette characterized by broad wings, a relatively short tail, and a prominent, erectile black crest on its head. The adult plumage displays a striking contrast: the upperparts, head, upper chest, and crest are a deep, glossy coal-black, whereas the underparts, belly, and heavily feathered thighs are a rich, vibrant chestnut-rufous with fine black streaks. Adult eyes are a piercing, bright golden-yellow. In stark contrast, juveniles exhibit a mostly whitish to pale gray head and underparts, with mottled brown upperparts, taking several years of successive molts to acquire the definitive adult coloration.

Geographical distribution: It is patchily distributed along the Andean mountain range of South America. Its range extends from northern Venezuela and Colombia, southward through the montane slopes of Ecuador, Peru, and Bolivia, reaching its southernmost limit in northwestern Argentina, specifically in the cloud forest provinces of Salta and Jujuy.

Habitat: This raptor is strictly tied to humid montane forests, cloud forests, and steep subtropical Andean woodlands, often referred to as Yungas. It is primarily recorded at elevations between 5,000 and 9,200 feet above sea level, although it can occasionally be found from 2,000 up to 11,500 feet. It demands vast tracts of unbroken forest canopy with towering, mature emergent trees to hunt, roost, and establish its nesting territories.

Feeding: Its diet is highly specialized, focusing mainly on medium-sized arboreal mammals that inhabit the canopy. Key prey species include coatis, woolly monkeys, capuchin monkeys, squirrels, and two-toed sloths. Large arboreal birds, particularly guans of the family Cracidae, also represent a significant portion of its prey. In areas encroached by human activities where its natural prey is scarce, it may opportunistically hunt domestic chickens and turkeys, which triggers severe human-wildlife conflicts with local farmers.

Behavior: It is a solitary or paired predator that maintains and aggressively defends massive home ranges. It utilizes thermal updrafts to soar effortlessly above the forest canopy, scanning the foliage below for any movement. Despite its large size, it exhibits extraordinary agility within the dense forest canopy, executing rapid, acrobatic pursuit flights and diving obliquely to snatch arboreal prey directly from the tree branches using its powerful talons.

Nesting: The nesting cycle of this avian species is remarkably long and demanding. Pairs build massive, bulky stick nests lined with green leaves that can exceed 6.5 feet in diameter and depth, situated high up in the forks of the tallest emergent forest trees, such as mature oaks of the genus Quercus. The female typically lays a single egg which is dull white with brown speckles. Incubation lasts around 45 days. The nestling remains in the nest for about 110 to 125 days before fledging. However, the juvenile remains highly dependent on its parents for food for up to a year, meaning that successful pairs usually nest only once every two years.

Conservation status: It is currently classified as Endangered (EN) on the IUCN Red List. The global population is critically small and declining rapidly. The primary threats are habitat loss and fragmentation driven by agricultural expansion, logging, and cattle ranching along the Andean slopes. Additionally, direct persecution and retaliatory shooting by local farmers who accuse the bird of preying on livestock pose a critical threat to its survival.