The bateleur (Terathopius ecaudatus) is a medium-sized colorful eagle native to broad areas of Sub-Saharan Africa and scarcely up into Arabia. Bateleurs are highly aerial birds that spend much time soaring. They have long been known to be declining rather pronouncedly in overall population and they are mostly confined to protected areas today.
The bateleur has a thick neck and a very large, rather conspicuously cowled head with a proportionately short bill, albeit one covered with a very large cere. The adult bateleur usually has a chestnut coloration along the mantle, back, rump, and tail, including the undertail coverts. The adult male bateleur is predominantly black with grey shoulders, which appear edged with white when freshly molted. The adult female differs by having grey-brown, not black, on the greater coverts and black-tipped grey, not black, secondaries. Furthermore, up to 7% of adults have a "cream morph" where they have chestnut tails but the other chestnut areas are almost fully replaced by cream to pale brown coloring. The bare parts of adult bateleurs are exceptionally conspicuous, with the adult cere, bare facial skin, and feet all being rather bright red, however, in some, they can also temporarily fade to pink, pale pink, or yellowish at times, such as when they are perching in the shade or bathing. The bare parts flush the most red during times of excitement. The bill itself is black with a yellow center and red base. The eyes are dark brown. Juvenile birds have longer a tail than mature birds. They furthermore have essentially all brown coloring, with dull rufous to creamy edging apparent on some areas. The head of the juvenile bateleur is paler and tawnier than elsewhere on its body while the eyes are brown, the cere a rather unique greenish-blue, and the feet whitish in color. In the 5th year, the plumage may show the first signs of chestnut and the grey color about the back and shoulders tend to manifest. Also from 3-5 years old, the cere and feet turn yellow then to dull-pink. By the sixth and seventh years of life, the plumage of subadult bateleurs blackens, and the chestnut portions of the plumage increase. The shoulders become fully grey by the 8th year, the likely age of maturity. As for the bare parts in juvenile bateleurs, the cere and facial skin are a distinct pale grey-blue to green-blue. The juvenile's feet are greenish-white to greyish-white, at 4-5 the cere, facial skin, and feet turn yellow, then pink before finally reddening. The eyes are similar in hue to those of adult bateleurs but are slightly lighter, being more honey-brown, while the bill of juveniles is mainly pale grey-blue in color.
Bateleurs range across Mauritania, Senegal, Mali, Guinea, Sudan, Ethiopia, Somalia, Namibia, Botswana, South Africa, Saudi Arabia, Yemen, Côte d'Ivoire, Kenya, Nigeria, Zambia, Zimbabwe, Togo, Tanzania. These are birds of the open savanna country and woodland (thornveld) within Sub-Saharan Africa; they also occur in south-western Arabia. Found in closed-canopy savannah woodland habitats, including Acacia savannah, Mopane and miombo woodlands. They are very common in broad-leaved woodland in the Okavango Delta. In Namibia, bateleurs are often found over tall woodland near drainage lines, and ephemeral rivers in north-eastern Namibia and within the more arid Etosha National Park.
Bateleur eagles are tree-nesting birds with a large home range. They live in pairs but each pair is territorial and in most areas lives alone. Bateleurs are generally silent but can produce a variety of barks and screams. These birds are active during the day spending a considerable amount of time on the wing. They hunt from swift, direct gliding flight across the country, or in wide sweeping circles. Bateleurs defend their territory by means of an aggressive attack flight pattern shown to intruding conspecifics. Males and females both display this behavior in all stages of the breeding cycle. This behavior is mainly shown to members of the same sex and particularly to non-adults. In the wild Bateleurs are shy of man and sensitive to disturbance at the nest, easily abandoning the structure. Bateleurs enjoy sunbathing; they frequently enter water-bodies for a bath and then open their wings to often sunbathe. Standing upright and holding their wings straight out to the sides and tipped vertically, a classic 'phoenix' pose as they turn to follow the sun. Bateleurs will also lie on the ground with their wings spread, exposing the feathers to direct sunlight, warming the oils in the feathers. The bird will then spread the oils with its beak to improve its aerodynamics.
Bateleurs are carnivores and scavengers; they will attack other species for food and will scavenge carrion. Bateleurs hunt birds and their eggs (mainly doves and pigeons), small reptiles, small mammals (like rodents, genets, and mongooses) and insects.
Bateleurs are monogamous; they mate for life and stay in the same nest for several years. The breeding season occurs from September-May in West Africa, throughout the year in East Africa and December-August in southern Africa, with a peak from January to April. Bateleurs are slow-maturing and slow-breeding species, laying only one egg at a time. Nests are stick platforms placed below the canopy of large trees such as thorny Acacia or knobthorn. Both parents put equal amounts of care into the young. Eggs are incubated around 55 days mainly by the female. Fledglings are ready to leave their nest about 110 days after hatching. Parents continue to feed their young for another 100 days and they become independent at 4 months of age. It takes young Bateleurs seven or eight years to reach full maturity.
Bateleurs threatened by loss of habitat, pesticides, capture for international trade and nest disturbance. In South Africa and Namibia these birds are being trapped, for their feathers to be used in medicine by traditional healers for predicting future events. The population has also decreased due to it feasting on poisoned animal carcasses being left out for other species. The Bateleur's wide foraging areas and their ability to locate very small pieces of carrion makes them highly susceptible to poison-laced carcasses even from a small proportion of farmers who use poisons.
According to the Wikipedia resource, the total population size of the Bateleur is around 10,000 to 100,000 individuals. Currently, this species is classified as Near Threatened (NT) on the IUCN Red List and its numbers today are decreasing.
