California Condor Life History
California condors (Gymnogyps californianus) were listed as endangered under the Federal Endangered Species Act on March 11, 1967. As of Oct 31, 2012, the total condor population was 409 birds and 232 of those were in the wild.
The California condor (Gymnogyps californianus) is a member of the family Cathartidae or New World vultures, a family of seven species, including the closely related Andean condor (Vultur gryphus) and the sympatric turkey vulture (Cathartes aura).
California Condors are the largest North American land birds and among the largest flying birds in the world. An adult condor will weigh about 22 pounds and can have a wingspan of up to 9.5 feet. Adults are mostly black with white underwing patches. Similar to their relatives, the vultures, they have no feathers on their heads or feet. Juvenile condors are grayish-black, with short feathers on their heads that they lose as they grow older. The bright orange-red colored head and the white patches under the wings are easy ways to distinguish adult California Condors from juveniles. Males and females cannot be distinguished by size or plumage characteristics.
Fossil records reveal that the California Condor once ranged over much of the southern United States, south to Nuevo Leon, Mexico, and east to Florida, as well as upstate New York. The disappearance of the condor from much of this range occurred about 10,000-11,000 years ago. By the time of the arrival of European settlers in western North America, condors occurred only in a narrow Pacific coastal strip from British Columbia to Baja California Norte. After the 1930s the condors were found primarily in central California, north of Los Angeles.
Once a condor reaches six or seven years of age, he or she is ready to find a mate for life. Condors will breed once every other year, with an elaborate courtship flight and dance leading up to mating. Before that, an appropriate nest site must be found. Condors build simple nests, often using caves in cliff faces to shelter their young from predators. Raising a condor chick requires tremendous energy and time, so a pair will usually lay only one egg per season. However, they may lay a replacement clutch if their first or even second egg is lost. The egg is incubated by both parents and hatches after approximately 56 days. Both parents share responsibilities for providing the nestling with food and warmth. At two to three months of age, condor chicks leave the nest but remain in the vicinity of the nest where they are fed by their parents. The chick takes its first flight at about six to seven months of age but may not become fully independent until the following year. Chicks learn from their parents how to fly and find food. Parents will look after their young up to two years after hatching.
Condors are obligate scavengers, meaning they feed only on carcasses of animals. A condor's sharp beak and strong neck muscles allow them to tear into animal hide and feed. They forage widely as far as 150 miles a day looking for deer, elk, livestock and marine mammals. Having located a potential food item, condors frequently remain in the air circling high above the carcass before landing. Circling behavior is thought to serve as a signal to other condors in the area, guiding them to potential food sources. Condors apparently depend on visual rather than olfactory cues to locate food. Having to face changes in food availability, condors have been documented not feeding for a periods up to 14 days.
Flight Patterns and Roosting Behavior
A condor can fly over a hundred miles in a single flight! They have a remarkable ability to soar on thermals, or currents of warm air that provide lift. This allows them to fly for a considerable distance without even flapping. Condors roost in tall snags or on cliff faces to elude terrestrial predators. Roosts may also serve a social function, as it is common for 2 or more condors to roost together and leave a roost together. Depending upon weather conditions and the hunger of a bird, a California condor may spend most of its time perched on a roost.
Reasons for Decline
Two anthropogenic factors, lead poisoning and shooting, have contributed disproportionately to the decline of the species in last 100 years. Although publicity associated with the condor recovery program has reduced the likelihood of condors being shot, one person was arrested as recently as 2004 for shooting a California condor. High lead levels, primarily obtained from the ingestion of fragments of lead bullets and shot remains a pervasive problem throughout the historical foraging range of the California condor. For more information, please see Lead Exposure.