13-9-2017 BIOPARC, VALENCIA - RUPPELL'S VULTURE (Gyps rueppelli)

Rüppell's vulture (Gyps rueppelli) is a large bird and its name comes from the 19th-century German zoologist and explorer Eduard Rüppell. It is native to the Sahel region and East Africa and its current population is decreasing due to loss of habitat, incidental poisoning, and other factors. Rüppell's vulture is considered to be the highest-flying bird, with confirmed evidence of a flight at an altitude of 11,300 m (37,000 ft) above sea level.

Both sexes of this species look alike: mottled brown or black overall with a whitish-brown underbelly and thin, dirty-white fluff covering the head and neck. The base of the neck has a white collar, the eye is yellow or amber, and the crop patch is deep brown. The head does not have feathers. This is an adaptation that occurred because of the Rüppell vulture's tendency to stick its head inside of its prey when eating. Without the adaptation, feeding would become extremely messy.

Rüppell's vultures are diurnal and very social birds, roosting, nesting, and feeding in large flocks. Like most vultures, they are silent, except when at their nesting ground or foraging around a carcass. They spend much of their time flying, gliding with wings held level, or using slow, powerful wing beats. They often fly at great altitudes, using strong winds or thermals for more efficient soaring. These vultures locate food by sight only, and once they see a carcass they swoop down, land a little way off, and then bound forward with wings spread and their long neck outstretched. Fights with other vultures are common as the birds struggle to get their meal, their necks often turning deep red from aggression as they hiss, grunt, and chatter at their opponent.

The Rüppell’s vulture inhabits the Sahel region in central Africa (Mali, Niger, Nigeria, Sudan, Chad, and others), living in sub-Saharan grassland and woodland. It often roots and breeds around cliffs and gorges.

Rüppell’s vultures are monogamous and form strong lifelong pair bonds. In vulture courtship, a pair will circle close together near cliffs. Pairs perch next to each other for a long time and together form colonies of as many as 1,000 breeding pairs. They build their large nests out of sticks and line them with grass and leaves. Females often steal sticks from other nests for the males to arrange. Depending upon the nesting site’s location, it may be used year on year or just once. Both parents take part in incubation, brooding, and feeding the chicks. A single egg is laid each year. Incubation is for 55 days. When the chick hatches, both its parents will feed it and look after it until it is about 150 days old when it fledges. After fledging a chick remains dependent on its parents, reaching independence when the next breeding season comes. Until then, they learn how to seek and compete for food.

This formerly abundant species has suffered a rapid decline over much of its range, especially in West Africa, and is now mostly confined to protected areas. Despite being less studied than other vultures, it is known that these declines are due to the impact of agriculture on their habitat, persecution, and large-scale incidental poisoning. In West Africa, these birds have been greatly used in black magic practices.

The IUCN Red List reports the Rüppell’s vulture total population size as 22,000 mature individuals, with perhaps about 30,000 individuals at the beginning of the 1990s. Specific populations have been estimated in these areas: 3,000 pairs in Tanzania; 2,000 pairs in Kenya; 2,000 pairs in Ethiopia; 2,000 pairs in Sudan and 2,000 pairs in West Africa. Overall, currently, Rüppell’s vultures are classified as Critically Endangered (CR) and their numbers today are decreasing.

The Ruppell's vulture is the highest-flying bird. Reportedly, a jet flying over the Ivory Coast at an altitude of 35,433 feet (10,800 meters) hit one! The Ruppell's vulture gets on the wing about two hours after sunrise and spends its entire day aloft.

Very social birds. Usually nest in loose colonies of up to 100 pairs, but have been seen in colonies up to 1,000 pairs. Colonies are found in open, arid areas. Prefers open areas, since they hunt for carcasses using sight, not smell.

Huge vulture, slightly smaller than Eurasian Griffon. Adults have dark-bodied with pale feather tips on body and shoulders, giving them a scaled appearance; also note pale bill and eye. Juveniles are dark with a characteristic pale bar on the leading edge of the underwings and have a black bill and dark eyes. Nests on cliffs and is generally silent except when squabbling at carcasses. Often encountered foraging over grasslands and soaring along cliffs and ridgelines.