Rüppell's vulture or Rüppell's griffon vulture (Gyps rueppellii) is a large vulture that occurs throughout the Sahel region of central Africa. The current population of 30,000 is decreasing due to loss of habitat, deliberate poisoning by ivory poachers 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). Rüppell's vulture is named in honor of Eduard Rüppell, a 19th-century German explorer, collector, and zoologist. 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.