|Black Vulture (Coragyps atratus) 25" long, WS 57"
The Black Vulture, which is seen in northern Mexico and less commonly in southern Arizona, closely resembles the Turkey Vulture both in habits and appearance, although it is slightly smaller, with shorter and broader wings. It has a black beak, and its facial coloring is black rather than red.
Despite their smaller size, Black Vultures are often more aggressive than Turkey Vultures and may take over a cadaver that the Turkey Vultures have located and chase them away from it. Unlike Turkey Vultures, which have a keen sense of smell, Black Vultures can find carrion only by sight--or by following the Turkey Vultures. Black Vultures were first reported in Arizona in 1920 and are relative newcomers, coming north from Mexico. They are now occasionally seen throughout the southeastern U.S. as well as northern Mexico. They are found in south central Arizona where they seem to favor lower elevations such as the Santa Cruz river drainage and Organ Pipe Cactus National Monument south of Tucson. They are still much less common than the Turkey Vulture in Cochise County.
Alderfer, Jonathan (ed.). Field Guide to Birds: Arizona and New Mexico. Washington, D.C.: National Geographic, 2006. This handy, pocket-size (4x6) guide includes most of the birds you're likely to see in Arizona. In addition to a photo, it includes information about behavior, habitat and specific local sites where you are likely to find the bird.
Corman, Troy E. and Cathryn Wise-Gervais (eds.) Arizona Breeding Bird Atlas. Albuquerque: University of New Mexico Press, 2005.
Sibley, David Allen. The Sibley Guide to Birds. New York: Alfred A. Knopf, 2000.