Introduction
The Black Eagle is a fairly common resident and one of the most thoroughly researched eagles in Southern Africa. This magnificent species gets its scientific name from the 18th century naturalist Jules Verreaux, hence “Aquila verreauxii”. Black Eagles are found at sea level from the Cape Province to the Drakensberg in Natal, to the Soutpansberg in the Northern Province and far beyond into the rock hills of southern Zimbabwe, Motobos Hills, where Cecil John Rhodes was laid to rest. The Motobos Hills is the home of the densest population of black eagles, this is the area where Val Gargett did her wondrous study of +/- 60 breeding pairs and wrote “The Black Eagle – A Study” well worth a read if you are passionate about raptors, especially black eagles.
The rugged or mountainous terrain with cliffs, rock ledges and caves is the preferred habitat of the black eagle. They occur in dry savannah, woodland and even desert and high rainfall areas, wherever rocky outcrops, gorges or mountain ranges provide nesting sites and there is an abundance of prey.
The Black Eagle is the finest of the genus Aquilla – a truly magnificent coal black bird with a white back and V on the shoulders. The handsome plumage is enhanced by consummate grace in flight … When perched, the small head and tapering neck gives the eagle an almost regal appearance. The juvenile Black Eagle, unlike the adult, is cryptically coloured and its plumage blends with broken rock, bush and trees of the surroundings. Feathered nestlings and juveniles are mottled brown, with a pale gold crown and nape, russet – brown mantle and neck, black cheeks and throat, cream forehead variously flecked with brown; the feathered legs, cream with light brown flecks; cere and toes, creamy yellow; bill grey, darker at tip; eye brown. Rump feathers are cream, edged brown; tail and flight feathers barred light and dark brown and with light fawn tips. In flight the young eagle shows the emerging pattern of ‘windows’ in the wing, the characteristic but less pronounced leaf – shaped wing and an indistinctly margined light rump.
These raptors are highly territorial and are often seen gliding together as they mate for life and assist each other in hunting sorties, hence their high success rate. In undisturbed natural habitat, hyraxes form up to 90% of prey, but small mammals, birds and reptiles are also caught. The Verreaux’s Eagle is one of the larger eagles in southern Africa (average length 90-cm/average weight 4-5 kilos,) with a wingspan of up to 2.3 m, this graceful raptor in flight is surely an unforgettable sight. The ceres, feet and eyebrows are yellow, their legs are feathered to their talons, and the eyes and bills are brown. In flight the wings are narrower near the body with the characteristic white “windows” in the primaries.
Black eagles, at any age, are more discomforted by heat than by cold. On hot, exposed nests they open their beaks and pant, even if there is no direct sunlight. Tiny chicks and down-covered eaglets seek shade by moving into the adults shadow or any patch of shade available on the nest.
The adults, like the nestlings, must obtain the liquid they need from their prey. Occasionally they have been observed bathing in the pond at the top of the waterfall.
Black Eagles have been seen ‘sunbathing’, that is, spread out on the ground or smooth rock in full sunlight, back to the sun, both wings outstretched and the tail fanned. This ensures that mites and parasites are removed from the feathers and the natural waxes within the feathers are heated, making it easier for the eagle to spread along the feather shaft during preening.
Black Eagles are not vocal birds as they rely more on visual communications, however the juvenile eagle is very vocal as it calls continuously to its mother on sight, for food and protection.
All observers agree on the magnificent flying powers of Black Eagles They make full use of thermals flowing round and over the hilly terrain of their preferred habitat, and move effortlessly across the sky, turning and circling, rising and gliding for long spells with seldom a wing beat. The characteristic leaf – shaped wing, is no doubt an adaptation for flying in rocky and mountainous terrain. The Black Eagles’ display flights are spectacular, if performed close to an observer, the whistle of air through their wings dramatically emphasizes the speed of their flight, with one flight pattern often merging imperceptibly with another.
Areas where black eagles are found in Africa