Verreaux’s Eagles (Aquila verreauxii), also known as the African Black Eagle or Black Eagle, is a large bird of prey. Its name commemorates the French naturalist Jules Verreaux.
Description
It is about 75 to 95 cm (30 to 38 in) in length, the average weight for males is 3.7kg (8lb 02oz) and for females 4.5kg (9lb 14oz) and has a wingspan of up to 2 m (6.7 ft).
It is generally black in colour with a distinct white V marking on its back.
Juveniles are usually light and dark brown in colour with a black face.
Structurally, it is very similar to the Golden Eagle of the Northern Hemisphere and the Wedge-tailed Eagle of Australia.
Habitat and Range
Verreaux’s eagles can be found in most of sub-Saharan Africa. Their range extends from South Africa to Namibia, Botswana, Zimbabwe, Kenya, Ethiopia and even into North Africa, where they are more isolated. They are widely distributed but not as widespread as some other raptors, since they are experts and confined to areas that support their needs.
The two main requirements are: mountainous terrain to nest in, and a healthy population of hyraxes as their preferred prey. Verreaux’s Eagles tend to be associated with cliffs and escarpments in arid and semi-arid habitats. They are neither forest dwellers nor creatures of the open savanna. They prefer highlands that have a mixture of vertical nesting rocks and scrubby vegetation. Hyraxes can be found among the rocks.
Most of them are resident birds. This means they don’t migrate long distances. However, they can spread out within their own territory if food is scarce. Territories can be large in areas with low hyrax populations. They may even cover 100 sq km or more. These eagles patrol the area regularly and are often one of the few signs of life on otherwise desolate terrains.
Breeding and Nesting
Verreaux’s Eagles have strong pair bonds. The pair is usually monogamous, and they form a pair that will last a lifetime. They often fly together and engage in aerial displays to strengthen their bond. They may perform synchronised soaring or talon-touching mid-air.
The breeding season is generally in the fall months. However, this can vary from region to region. The pair builds an enormous Nest or Aerie. This is usually constructed on a cliff ledge. The nests can be huge, up to two meters in width and one meter in depth. They are made of sticks and branches and covered with grass or animal hair. Many pairs will return to the nest each year and add to it as the seasons progress.
The female usually lays 2 creamy white eggs at a distance of a few days. It is common among large raptors. However, only one chick survives. The first chick that hatches often kills or prevents the second from getting enough food — a brutal, but natural survival technique called siblicide. The incubation period lasts about 45 days. During this time, the female sits mainly on the eggs, and the male brings food.
The chick will depend on its parents to provide food and protection for a period of several months. The chick leaves the nest at about 95 to 100 days old, but can remain near the nest for several weeks. The young may remain in the territory of their parents for six months or more, where they learn to hunt and fly before finally dispersing. According to Audubon Society, this species is well documented.
Hunting and Diet
highly specialised diet is one of the most intriguing aspects of the Verreaux’s Eagle. It is the only raptor that specialises in hyrax. The eagle feeds primarily on hyraxes. These small mammals, which look like guinea pigs, are much larger, and their number directly affects the size of their territory. Verreaux Eagles can raise chicks and maintain smaller territories in areas where hyraxes thrive. When hyrax numbers drop, territory sizes increase, and breeding can be rare or even fail. According to Cornell Lab of Ornithology, this species is well documented.
They are hard to catch. They are very alert and post sentinels in order to keep an eye out for predators. Verreaux’s Eagle evolved a strategy that allows it to outmaneuver its predators. It scans for movement in the rocks using high altitude soaring. It folds its wings, dives and strikes with deadly precision when it spots prey. Its powerful claws can kill a hyrax in an instant, and may even carry it back to its nest or eat it on nearby perches.
Verreaux’s Eagle does not only eat hyraxes. Verreaux’s Eagle will also eat birds like guineafowls, rock pigeons and francolins as well as small- to medium-sized mammal species such as hares or mongooses. It is not a carrion scavenger, but it does take some.
Voice and Communication
Verreaux’s EEaglearis ea relatively silent species in comparison to other raptors. It communicates primarily visually, through flight displays, postures and movements, rather than by sound. They are not completely silent, however. When courting or near the nest, a pair will emit a series high high-pitched whistles or yelps. This is especially true when the first bird enters the nest or leaves to hunt. The calls are usually short and not very loud. They can be easily missed unless you’re close.
The parents are alerted to the needs of their hungry chicks by loud begging. The chick’s vocal begging increases in intensity as it grows bigger and more demanding. It is common to hear this begging echo off the cliff face during nesting season.
Conservation Status
The Verreaux’s Eagle, although not considered globally endangered, is becoming the subject of conservation concerns. This is especially true in areas where habitat destruction and encroachment by humans reduce suitable hunting and breeding grounds. The hyraxes are also a threat to the Verreaux’s Eagle because of their dependence.
Hyraxes, which are considered agricultural pests in some parts of Africa, are poisoned, trapped, or hunted. This has unintended consequences on the eagles who depend on them. Rock-climbing, mining and infrastructure development are also affecting nesting sites in mountainous areas and decreasing breeding success.
Conclusion
Verreaux’s eagle is a majestic bird, dark as night and bearing a white, gleaming mark that resembles a pride banner. This eagle is a symbol for Africa’s mountainous landscape, a sentinel who watches from the highest crags while hunting with elegance and efficiency. This eagle, with its powerful talons and its devotion to one mate for life, is both mysterious and majestic.
It is also a stark reminder of the fragility of nature. The Verreaux’s Eagle is a specialist and cannot adapt to any type of environment. It can only thrive in ecosystems that support its unique needs. As these ecosystems shrink and change, their future is also in danger.
Their serving this eagle means preserving Africa’s wild, rocky highlands where the sky meets the stone and the ancient dance between predator and prey is still played out away from the crowds. For those who are lucky enough to witness this bird’s flight, with its wings spread out and gliding over the cliffs, it is a sight not soon forgotten.
The silent flight of Verreaux’s Eagle in a world that is becoming more and louder reminds us to appreciate the beauty of nature and our responsibility to protect it.
References
- Mearns, Barbara; and Mearns, Richard. (1988). Biographies for Birdwatchers. The lives of those commemorated in Western Palaearctic bird names. Academic Press: London. ISBN 0-12-487422-3
- BirdLife International (2004). Aquila verreauxii. 2006. IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 6 May 2006. The database entry includes justification for why this species is of least concern
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