Rüppell's Vulture

Rüppell's vulture (Gyps rueppelli), also called Rüppell's griffon vulture, named after Eduard Rüppell, is a large bird of prey, mainly native to the Sahel region and East Africa. The current population of 22,000 is decreasing due to loss of habitat, incidental poisoning, and other factors. Known also as Rüppell's griffon, Rueppell's griffon, Rüppell's griffin vulture, Rueppell's vulture and other variants, it is not to be confused with a different species, the griffon vulture (Gyps fulvus). The Rüppell's vulture is a large vulture, noticeably outsizing the closely related white-backed vulture, with which they often occur in the wild. Adults are 85 to 103 cm long, with a wingspan of 2.26 to 2.6 m, and a weight that ranges from 6.4 to 9 kg. Both sexes 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, the crop patch 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. Silent as a rule, they become vocal at their nest and when at a carcass, squealing a great deal. The birds have a specialized variant of the hemoglobin alphaD subunit; this protein has a great affinity for oxygen, which allows the species to absorb oxygen efficiently despite the low partial pressure in the upper troposphere.