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Condors

Return to the wild

Condors are New World vultures that are among the largest of flying birds. There are only two species, the Andean condor (Vultur gryphus) and the critically endangered California condor (Gymnogyps californianus). They are related to the smaller vultures of the Americas, including the king vulture (Sarcoramphus papa) and turkey vulture (Cathartes aura), which also belong to family Cathartidae. In the same family, but extinct for about 10,000 years was the largest flying bird that ever lived. This was Teratornis incredibilis, a vulture found in the southwestern United States that had a wingspan of at least 16 ft (4.9 m).

The combined head and body length of the living condors is about 50 in (127 cm), and they weigh 20–25 lb (9–11 kg). They have black or dark brown plumage with white patches on the underside of the wings. The California condor has a wing span of 9 ft (2.7 m), while that of the Andean condor is 10 ft (3.1 m). Both species have a ruff of feathers around the neck, colored black on the California condor and white on the Andean. Both condors have a bald head and a short, sharply hooked beak. The Andean condor's naked skin is red, while that of the California condor is pinkish orange. The Andean male has an extra fleshy growth on top of its head, rather like a rooster's comb. The California condor does not have this growth.

The range of the Andean condor extends throughout the high Andean Mountains, and much of this habitat remains wild. It can fly over the highest peaks, but may land on lower-lying fields to scavenge dead animals. Although rare, this species still exists in relatively large numbers.

The California condor, however, is one of the most critically endangered animals on Earth. Historically, its range extended over much of North America, when it once foraged for carcasses of large ice age mammals. However, the condors began to decline at about the same time that many of these large mammals became extinct, around 10–12 thousand years ago. By the time of the European settlement, the range of the California condor was restricted to the western coast and mountains. As human populations in the region grew, the condor population declined further. By the 1950s its range was restricted to a small area of central California surrounding the southern end of the San Joaquin valley. In recent decades, condor habitat has been further disrupted by petroleum drilling, planting of citrus groves, and residential developments. In addition, rangeland where dead cattle might have been scavenged was extensively converted to cultivated fields of alfalfa and other crops. California condors have also suffered lead poisoning after ingesting lead shot or bullets in carrion. They have also been affected by DDT and other insecticides.

California condors lay only a single egg. After hatching, it takes the young condor 18 months to develop its wings sufficiently for flight. During that time, the chick is vulnerable to cold or hunger, especially when its parents fly far to forage for food, leaving the chick exposed for an extended time. It takes six years for a California condor to attain sexual maturity. Because of its low fecundity, its population cannot sustain much mortality.

It was obvious by the 1950s that California condors were in danger of extinction. In 1978, there were only about 30 birds left in the wild, and seven years later only nine. At that time, all wild California condors were captured by the Fish and Wildlife Service and taken to the San Diego Wild Animal Park and the Los Angeles Zoo, where several other condors were already in residence. The zoos began a captive breeding program for the California condor, and by 1996, 103 individuals were alive. The population recovery has been sufficient to allow some birds to be introduced back into the wild.

To test ideas about how best to return condors to the wild, several Andean condors were brought to the United States and released in a national forest. It quickly became apparent that there were too many human activities and influences in the area for the condors to be reintroduced successfully. They had to be released farther from civilization. To this end, the Sespe Condor Sanctuary was acquired by the Fish and Wildlife Service as a wilderness habitat for these endangered birds. First two, then several additional California condors were released to this area. When several birds were poisoned by bullets in carrion they ate, it became clear that the reintroduced birds would have to be provided with safe food until their numbers increased. In late 1998, 22 condors were in the wild in southern California and 14 in Arizona. The ultimate goal is to establish at least two separate populations of more than 150 birds each.

The California condor has received a reprieve from extinction, but its survival depends on the continuation of intensive management efforts and the conservation of sufficient habitat to sustain a viable breeding population.


Resources

Books

Caras, Roger A. Source of the Thunder: The Biography of a California Condor. Lincoln, NE: University of Nebraska Press, 1991.

Peters, Westberg. Condor. New York: Crestwood House, 1990.

Silverstein, A., V. Silverstein, and L. Nunn. The California Condor. Millbrook Press, 1998.


Jean F. Blashfield

Additional topics

Science EncyclopediaScience & Philosophy: Condensation to Cosh