Bateleur
Terathopius ecaudatus
Accipitriforme Order – Accipitridae Family
BIOMETRICS :
Length : 60cm – Wingspan : 187 cm – Weight : 1800 to 2900 g
LONGEVITY : 25 years
DESCRIPTION:
Bateleur is an African Eagle with long wings and very short tail. It is a colourful raptor, and one of the most beautiful.
Some African Tribes revere Bateleur, believing that they will win a battle if the eagle flies over the enemy.
Adult male has black head, neck, breast, greater wing coverts, belly and thighs. Shoulders are pale grey. Mantle, rump and tail are chestnut. Underwings are black and white with broad black trailing edges. Undertail coverts are chestnut.
Bateleur has black eyes bordered with red eye ring. Bare face is bright red. Hooked bill is yellowish with black tip. Stocky legs and short stubby toes are bright red.
Female is slightly larger than male. She has greyer shoulders and grey secondary flight feathers above. Underwings are black and white, with narrow black trailing edge.
Juvenile is reddish-brown on head and underparts. Upperparts are darker brown. Underwings show broad or narrow dark brown trailing edged, as in adults, according to the sex. Juvenile and immature have bluish facial skin and bill, with black tip. Eyes are brown. Legs and feet are pale bluish grey. Subadult is sooty black on both sides, with mixed dark and white flight feathers, all dark in male. Face and legs become orange before to turn red as in adult.
They reach their full maturity at about 7 years.
VOICE: SOUNDS BY XENO-CANTO
Bateleur utters short “kau-kau-kau” repeated and followed by two mostly long “koaagh”. It often calls when perched. It is usually silent, but it sometimes utters loud screams if excited.
While calling, it raises its half spread wings, giving the bird a threat posture, used in territorial displays.
HABITAT:
Bateleur lives in bushy savannahs, open woodlands, coastal plains and semi-deserts. It is found from sea level up to about 14.000 feet (4200m). It breeds at about 7.000 feet (2100m) of elevation, in rocky uplands.
RANGE:
Bateleur lives throughout Africa south of the Sahara, and eastwards into SW Arabia.
BEHAVIOUR:
The Bateleur feeds on several kinds of food, but also venomous snakes. When it attacks a snake, Bateleur raises its crest feathers and spreads its wings. It has scaly legs to protect it against the venom. If a snake strikes it, any venom will pass into bird’s blood stream.
The Bateleur spends most of time of the day on the wing, soaring effortless. It may takes off when the warmth starts, and it flies almost the entire day, until the cooler hours of the evening. It may fly over 320 km every day, during 8 to 9 hours. During the day, it sometimes perches in a tree, close to carrion, where it may try to pirate smaller raptors. When not in flight, the Bateleur perches or stands on the ground near water.
During the breeding season, the Bateleur is well known for its wonderful flight displays. It can execute 360 degrees rolls, displaying amazing turns and somersaults in the air. Male also performs steep dives to female. Then, she rolls on her back and presents her claws to the male, and they hurtle each other.
When birds perform their “barrel-rolls”, this display is often accompanied by very loud slapping of the wings. This noise can be heard for great distance. Courtship flight displays are accompanied by loud crowing calls.
This eagle performs a kind of mating-dance on the ground, in order to expose its beautiful coloured plumage.
Bateleur enjoy the sun, standing upright and holding wings straight out to the sides. The bird turns to follow the sun.
Bateleur pairs for life and reuses the same nest year after year. It is a sociable species, but the pair is territorial and lives alone in most areas.
Bateleur adult is territorial and often resident in most parts of the range. The juveniles may perform nomadic movements.
FLIGHT:
The Bateleur’s short tail allows it to rock side to side in flight, while it is rapidly soaring. Its name “Bateleur” means “balancer”.
During the day, it may fly at speeds of up to 50 mph (80km-h). It is an excellent flyer. It performs distinctive aerial acrobatics during courtship displays.
REPRODUCTION:
Bateleur builds its nest in high tree, and this place is reused for several years. Both adults build the nest in an open fork. This one is located in riparian zone or in a large isolated tree in woodland, but often near a watercourse. Preferred trees are thorny Acacia and Baobab. The nest is situated in a sheltered area of the tree, and it is not open to the sky. Construction is made with heavy sticks. The deep cup is lined with green leaves.
The female lays one chalky white egg at dry season. Incubation lasts about 52 to 59 days, mainly by female, but male sometimes assists her. The male feeds the female close to the nest, or sometimes it gives her by aerial food pass. Chicks are fed by both parents.
Young leaves the nest about 110 days after hatching, but parents continue to feed it for another 100 days. Young is independent at 4 months of age. It has a longer tail than adults for stability, which helps it during the first flights.
We can see sometimes unpaired adult near the nest site. This bird may be a previous clutch’s young. It can help to guard and defend the nest, but it doesn’t feed the youngest.
FOOD HABITS:
The Bateleur feeds on carrion (road kills) and live animals such as young hares, hedgehogs, mice, rats, squirrels and reptiles. They also may eat fish and some ground birds.
It hunts while flying low from the ground, at about 50 metres high, searching for preys. When the prey is detected, the eagle drops in spiral on it.
PROTECTION / THREATS:
Bateleur is threatened by hunting and poisoning, and some declines occur in most parts of its original range. Persecution, nest disturbances and habitat loss are the most important threats in southern Africa.
Predators of Bateleur are larger birds of prey.
This species is still relatively common in most parts of the range.
Photographer:
Callie de Wet
GALLERY
Text by Nicole Bouglouan
Fr: Bateleur des savanes
Esp: Aguila Volatinera
Ital: Falco giocoliere
Nd: Bateleur - Goochelarend
Sources:
HANDBOOK OF THE BIRDS OF THE WORLD Vol 2 by Josep del Hoyo-Andrew Elliot-Jordi Sargatal - Lynx Edicions - ISBN: 8487334156
The Hawk Conservancy Trust (Hilary Smith)
Wikipedia (Wikipedia, The Free Encyclopedia)