27 April 2010

Verraux's eagle, Black eagle (Witkruisarend)

Location: Augrabies Waterfalls
Scientific name: Aquila verreauxii




Verreaux's eagle is a very large eagle. It measures 75 to 96 cm (30 to 38 in) long from the bill to the tip of the tail, making it the sixth longest eagle in the world. The average weight is approximately 4.19 kg (9.2 lb). Other than the female’s slight size advantage, adult males and females are physically indistinguishable from each other. Adult Verreaux's eagles are mostly jet-black in color. The yellow coloration of the cere (the bill is gun-metal grey), eye-ring and “eye-brows”, all stand out in contrast to the black plumage. Even more prominent on flying birds when seen from above is the white on the back, rump and upper-tail coverts and part of the scapulars, which forms a V-shaped patch, although this feature is partially obscured in perched birds. uvenile and immature plumages differ markedly from the plumage of adults. They are overall a dark brown color. Immatures have a strongly contrasting golden crown and a rufous or ginger nape and mantle. They have small white streaks on the forehead and black on their cheeks. The throat is dark streaked, the lower throat is pale brown and the upper-chest is brown. The rest of the underside is brown but for a blackish-blotched rufous to cream-colored abdomen and lightly marked creamy thighs and legs.
In southern Africa, it is locally fairly common in Zimbabwe, Namibia and South Africa, marginally extending into eastern Botswana and western Mozambique. It generally prefers mountains and other rocky habitats with cliffs.
It mainly eats mammals, especially rock hyraxes, doing most of its hunting from a perch, from which it descends to pluck prey from the ground. It often hunts in pairs, so that one bird can flush prey by skimming the rockface, while the other follows to strike; they share the meat afterwards. It tends to hunt rock hyraxes in the early morning and evening, when they take up exposed positions to warm up; it sometimes surprises the hyraxes to such an extent that they fall down the rockface to their deaths.