Immature California Condor
There are two species, each in its own monotypic genus:
- The Andean Condor (Vultur gryphus) which inhabits the Andes mountains.
- The California Condor (Gymnogyps californianus) nowadays restricted to western coastal mountains of the United States.
Although they are primarily scavengers, feeding on carrion, these species belong to the New World vulture family Cathartidae, most likely closer related to the storks instead of Old World vultures. The latter are in the diurnal raptor family Accipitridae along with hawks, eagles and kites.
Both condors are very large broad-winged soaring birds, the Andean Condor being 5 cm shorter (beak to tail) on average than the northern species, but larger in wingspan.
Measurements are usually taken from specimens reared in captivity.
The adult plumage is of a uniform black, with the exception of a frill of white feathers nearly surrounding the base of the neck and, especially in the male, large patches or bands of white on the wings which do not appear until the completion of the first moulting. As an adaptation for hygiene, the head and neck have few feathers (see below photo), exposing the skin to the sterilizing effects of dehydration and ultraviolet light at high altitudes, and are meticulously kept clean by the bird. The head is much flattened above. In the male it is crowned with a caruncle or comb, while the skin of the neck in the male lies in folds, forming a wattle. The skin of the head and neck is capable of flushing noticeably in response to emotional state, which serves to communicate between individuals.
The middle toe is greatly elongated, and the hinder one but slightly developed, while the talons of all the toes are comparatively straight and blunt. The feet are thus more adapted to walking as in their relatives the storks, and of little use as weapons or organs of prehension as in birds of prey and Old World vultures. The female, contrary to the usual rule among birds of prey, is smaller than the male.
Sexual maturity and breeding behavior do not appear in the condor until 5 or 6 years of age. They may live for 50 years or more, and mate for life.
The young are covered with a grayish down until almost as large as their parents. They are able to fly after six months, but continue to roost and hunt with their parents until age two, when they are displaced by a new clutch. There is a well developed social structure within large groups of condors, with competition to determine a 'pecking order' by body language, competitive play behavior, and a wide variety of vocalizations, even though the condor has no voice box.
On the wing the movements of the condor, as it wheels in majestic circles, are remarkably graceful. The lack of a large sternum to anchor correspondingly large flight muscles identifies it physiologically as a primarily soarer. The birds flap their wings on rising from the ground, but after attaining a moderate elevation they seem to sail on the air.
Wild condors inhabit large territories, often traveling 250 km (150 miles ) a day in search of carrion. They prefer large carcasses such as deer or cattle which they spot by looking for other scavengers, which cannot rip through the tougher hides of these larger animals with the efficiency of the larger condor. In the wild they are intermittent eaters, often going for a few days without eating, then gorging themselves on several kilograms at once, sometimes to the point of being unable to lift off the ground.