Francisco Marquez / Griffon vultures (Gyps fulvus) and European black vultures (Aegypius monachus) feeding on a dead deer, Cabaneros National Park, Montes de Toledo, Spain, May.

Fabrice Cahez / Eurasian griffon vulture (Gyps fulvus) in flight above clouds, Gorges du Tarn, France, January.

Fabrice Cahez / Eurasian griffon vulture (Gyps fulvus) in flight above clouds, Gorges du Tarn, France, January.

Bernard Castelein / Cinereous / European Black Vulture (Aegypius monachus) in dispute with an Eurasian Griffon Vulture (Gyps fulvus), alongside a Himalayan Griffon (Gyps himalayensis) and Long-billed Vulture (Gyps indicu...

Staffan Widstrand / RF - Cinereous vulture (Aegypius monachus) juvenile, portrait. Calera y Chozas, Castile-La Mancha, Spain. December. (This image may be licensed either as rights managed or royalty free.)

Staffan Widstrand / RF - Cinereous vulture (Aegypius monachus) juvenile, portrait. Calera y Chozas, Castile-La Mancha, Spain. December. (This image may be licensed either as rights managed or royalty free.)

Staffan Widstrand / RF - Cinereous vulture (Aegypius monachus) with wings spread, running towards feeding vultures to dominate and chase them away from food. Calera y Chozas, Castile-La Mancha, Spain. December. (This ima...

Staffan Widstrand / Cinereous vulture (Aegypius monachus) portrait. Calera y Chozas, Castile-La Mancha, Spain. December.

Staffan Widstrand / Cinereous vulture (Aegypius monachus) portrait. Calera y Chozas, Castile-La Mancha, Spain. December.

Staffan Widstrand / Cinereous vulture (Aegypius monachus) juvenile with wing spread, portrait. Calera y Chozas, Castile-La Mancha, Spain. December.

Dave Watts / White rumped vultures (Gypes bengalensis) and Cinerous vulture (Aegypius moachus)coming in to feed on a dead buffalo, Chitwan National Park, Nepal.

Dave Watts / Mixed flock of Himalayan griffon vultures (Gyps himalayensis) and European black vulture (Aegypius monachus) feeding on dead goat, near Mardi Himal, Annapurna Range, Nepal.

Dave Watts / Mixed flock of Himalayan griffon vultures (Gyps himalayensis) and European black vulture (Aegypius monachus) feeding on dead goat, near Mardi Himal, Annapurna Range, Nepal.

Dave Watts / Mixed flock of Himalayan griffon vultures (Gyps himalayensis) and European black vulture (Aegypius monachus) resting on a clifftop after feeding, near Mardi Himal, Annapurna Range, Nepal.

Dave Watts / Mixed flock of Himalayan griffon vultures (Gyps himalayensis) and European black vulture (Aegypius monachus) feeding on dead goat, near Mardi Himal, Annapurna Range, Nepal.

Staffan Widstrand / Young Black or Cinereous vulture (Aegypius monachus) Gredos Mountains, Castilla La Mancha, Spain

Fabrice Cahez / Cinereous vulture (Aegypius monachus) in flight, Cevennes National Park, France, March.

Fabrice Cahez / Cinereous vulture (Aegypius monachus) in flight, Cevennes National Park, France, March.

Fabrice Cahez / Cinereous vulture (Aegypius monachus) in flight, Cevennes National Park, France, March.

David Tipling / Eurasian black vulture (Aegypius monachus) in aggressive posture approaching food and other vultures Sierra San Pedro, Extremadura, Spain. December

David Tipling / Eurasian black vulture (Aegypius monachus) Sierra San Pedro, Extremadura, Spain. December

David Tipling / Eurasian black vulture (Aegypius monachus) in aggressive posture approaching food and other vultures Sierra San Pedro, Extremadura, Spain. December

David Tipling / Griffon (Gyps fulvus) and Black vultures (Coragyps atratus) fighting over food Sierra San Pedro, Extremadura, Spain. December

David Tipling / Eurasian black vulture (Aegypius monachus) in aggressive posture approaching food and other vultures Sierra San Pedro, Extremadura, Spain. December

David Tipling / Eurasian black vultures (Aegypius monachus) fighting, Sierra San Pedro, Extremadura, Spain. December

David Tipling / Eurasian black vulture (Aegypius monachus) Sierra San Pedro, Extremadura, Spain. December

David Tipling / Eurasian black vulture (Aegypius monachus) Sierra San Pedro, Extremadura, Spain. December

David Tipling / Eurasian black vulture (Aegypius monachus) Sierra San Pedro, Extremadura, Spain. December

David Tipling / Eurasian black vulture (Aegypius monachus) Sierra San Pedro, Extremadura, Spain. December

Klein & Hubert / European black vulture (Aegypius monachus), Spain.

Francisco Marquez / Juvenile European black vulture (Aegypius monachus) preening in nest, Cabaneros National Park, Montes de Toledo, Spain, July.

Francisco Marquez / Juvenile European black vulture (Aegypius monachus) chick in nest, Cabaneros National Park, Montes de Toledo, Spain, July.

Francisco Marquez / Juvenile European black vulture (Aegypius monachus) feeding in nest, Cabaneros National Park, Montes de Toledo, Spain, July.

Francisco Marquez / European black vultures (Aegypius monachus) grooming each other, with a Griffon vulture (Gyps fulvus) resting on the ground nearby, Cabaneros National Park, Montes de Toledo, Spain, May 2012.

Francisco Marquez / Griffon vultures (Gyps fulvus) and European black vultures (Aegypius monachus) feeding on a dead deer, Cabaneros National Park, Montes de Toledo, Spain, May.

Francisco Marquez / Griffon vultures (Gyps fulvus) and European black vultures (Aegypius monachus) feeding on a dead deer, Cabaneros National Park, Montes de Toledo, Spain, May.

Francisco Marquez / Griffon vultures (Gyps fulvus) and European black vultures (Aegypius monachus) feeding on a dead deer, Cabaneros National Park, Montes de Toledo, Spain, May.

Francisco Marquez / Griffon vultures (Gyps fulvus) and European black vultures (Aegypius monachus) feeding on a dead deer, Cabaneros National Park, Montes de Toledo, Spain, May.

Fabrice Cahez / Cinereous vulture (Aegypius monachus) in flight, Cevennes, France, March.

Luke Massey / Cinerous vulture (Aegypius monachus) portrait, Extremadura, Spain October.

Luke Massey / Cinerous vultures (Aegypius monachus) squabbling, Extremadura, Spain October.

Luke Massey / Cinerous vulture (Aegypius monachus), Extremadura, Spain October.

Francisco Marquez / Griffon vultures (Gyps fulvus) and European black vultures (Aegypius monachus) feeding on a dead deer, Cabaneros National Park, Castile-La Mancha, Spain, May.

Andres M. Dominguez / Black vulture (Aegypius monachus) preening, El Barraco, Avila, Spain, June.

Dong Lei / Cinereous vulture (Aegypius monachus) and Himalayan griffon (Gyps himalayensis) with stupas in the background, Napahai Lake, Zhongdian County, Yunnan Province, China. January.

Dong Lei / Cinereous vulture (Aegypius monachus) on ground, Napahai Lake, Zhongdian County, Yunnan Province, China. January.

Fabrice Cahez / Monk vulture, (Aegypius monachus) in flight, Gorges de la Jonte, France, December

Fabrice Cahez / Eurasian griffon vulture (Gyps fulvus) group in flight above clouds, Gorges du Tarn, France, January.