Vultur gryphus
Andean condor

Andean condors (Vultur gryphus) inhabit most of western South America in the mountains and deserts ranging from western Venezuela south to Tierra del Fuego. Andean condors can be found in Columbia, Bolivia, Ecuador, Peru, Chile, and Argentina. The wild population was thought to be extirpated from Venezuela but is very rarely still seen there.

In an isolated network of mountain peaks in the Andes of Columbia and Ecuador, the population is thought to be in decline. Populations reach much higher densities in the regions south of the Northern Peruvian Low, were they inhabit vast areas of highland prairie, desert, and coastal regions. (Hendrickson, et al., 2003; Rios-Uzeda and Wallace, 2007)

Andean condors inhabit mountain and coastal mountain habitat types in the Andean mountains of South America. They have been located at elevations of up to 5,500 m. They prefer areas with wide open spaces which aid in their detection of food. Andean condors roost and nest on cliff faces in small rock ledges or caves. They use the thermals that rise and spiral off of these cliff faces to soar for hours with very little effort, scanning for carrion. (Lambertucci, et al., 2009; Rios-Uzeda and Wallace, 2007)

Andean condors have dark feathers in maturity (while juveniles are olive-grey and brown), with a white collar or downy plumage around the base of their necks. They also have white flight feathers on their wings as adults, with those of the male being more pronounced. When extended, the wing tips have gaps between the primaries which is an adaptation for soaring. The head and neck of adult condors are bare of feathers and are generally black to dark reddish brown, while juveniles have much darker skin and young hatchlings have fluffy grey down on their bodies. This baldness is presumably a hygienic adaptation, as the bare skin is easier to keep clean and dry after feeding on carrion. The beak is hooked at the end and functions in tearing rotting meat off a corpse. The bases of their upper and lower mandibles are dark with the rest of the beak being ivory colored. Andean condors weigh between 7.7 and 15 kg and range from 97.5 to 128 cm in length. Their wingspan of 3.2 m is the longest wingspan of any land bird.

Andean condors are the only species in the family Cathartidae that exhibit drastic sexual dimorphism. Unlike many other birds of prey, male Andean condors are considerably larger than the females. Also, males have a large caruncle (comb) and wattle which females lack. Sexes differ in eye color as well, with males having brown irises and females having red. Both sexes have the ability to change the color of the bare skin on their neck and face in association with mood. This is used for communication between individuals and males also use this for displays during mating season.

The feet of Andean condors are much less powerful with shorter blunted talons compared to those of other birds of prey. This adaption is well suited for a lifestyle of walking and scavenging. The hind toe is less developed, but the middle toe is much longer that the other toes. Their feet and legs are covered in circular scales that are dark grey in color. (Lambertucci and Mastrantuoni, 2008)

A pair of Andean condors may select a nest site and then roost in (or near) it for as much as two and a half months before mating actually begins. As the pair mate and the time draws near to the female laying their egg, they will gradually begin to roost closer and closer to the nest ledge until they are finally roosting overnight inside it.

The mating behavior of Andean condors differs between accounts in zoo settings and the limited observations of wild birds. Accounts of wild birds have been made at great distances without clear views or description of the display or copulatory behavior. The male display can begin with pre-display behavior that includes the male rubbing his head and neck against a tree or post. Also the male has been described to present the female with small twigs and straws that they both lodge in their wing feathers, immediately followed by the object falling to the ground. These behaviors were not observed in all cases, and no definite explanation was offered. It is loosely hypothesized that the stick behavior may be remnant of when the species ancestors were nest builders but no formal studies have been conducted.

In general the male begins to display by spreading his wings and inflating his neck. His neck and wattle, which are normally a dull pinkish-grey color, flush a bright sulfur yellow. He approaches the female with his wings spread and his neck outstretched and arched with his bill pointing down. The male makes small turns to the left and right as he waddles toward the female who also may spread her wings and mimic his movements. The male hisses as he approaches the female, who may reply with low moaning sounds during copulation. The pair may nibble at each other for several minutes and click their bills together. Nibbling can continue during and after copulation.

Courtship and mating seem to be intricately tied to the males role as a dominant partner and the females submissiveness to him, which may account for the variation in observed behaviors from pair to pair, if each pair has a different balance of dominance in the relationship. (Gailey and Bolwig, 1973; Lambertucci and Mastrantuoni, 2008; Whitston and Whitston, 1969)

The mating season of Andean condors varies geographically, but is generally from February through June. They are non-migratory so seasonal extremes are very different in the northern and southern extents of their range. Breeding interval is also likely variable depending on the quality of their habitat and the availability of food.

Observations of breeding in Andean condors have been documented in great detail in only a few instances. This makes generalizing their behavior difficult due to variation between observations.

Most Andean condors do not construct a nest and will lay a single egg on the bare, cliff ledge. Some condors will collect a few sticks to scatter around the ledge. Eggs are bluish-white in color, weigh about 280 g, and are 7.6 to 10.1 cm in length. The single egg is incubated for 54 to 58 days, after which an altricial, downy chick hatches. Chicks are tended by both parents until they fledge at 6 to 7 months old. Fledglings remain with their parents until 2 years old, or when pairs breed again. Juveniles do not reach sexual maturity until 6 to 11 years of age. (Lambertucci and Mastrantuoni, 2008)

Both sexes participate in incubation of the eggs and feeding the young. The sexes alternate incubation, with one of the pair always at the nest for the first 1 to 2 months. The parents continue alternating time at the nest for an additional month but gradually spent more time off the nest, but near the nest site. Males may forcibly displace females from the egg to take over incubation. Males have also been observed frequently chasing the females out of the nest before and after hatching. Males also feed the young more often than the females do. Parents tend the young well after they fledge at 6 to 7 months of age. Juveniles remain with the parents for an average of 2 years, or until parents breed again. (Lambertucci and Mastrantuoni, 2008)

Andean condors are long lived birds that mature slowly. Their true maximum lifespan in the wild is unknown but is estimated at around 50 years.

In January of 2010 a wild-born, captive condor died at nearly 80 years old at the Beardsley Zoo in Bridgeport Connecticut.

Andean condors are monogamous and are thought to mate for life. They are active during the day and spend most of their time soaring. Both adults and juveniles are known to roost communally on ledges and shelves to rest, but not to breed as other vultures do. Large numbers (196) of condors have been observed at communal roosts in Patagonia, Argentina. Use of roost sites increases during the summer and autumn. The social interactions at roost sites show a dominance hierarchy with males dominating over females and adults dominating over juveniles. This dominance behavior led to segregation of roost sites with dominant individuals preferentially occupying certain roosts with optimal sun exposure and wind protection.

Like many vultures, Andean condors also exhibit the cooling mechanism of urohydrosis. Lower body temperatures are achieved through evaporation after excreting on their own legs. Their legs are thus often stained white with uric acid. (Donázar and Feijoo, 2002; Lambertucci, et al., 2008; Wallace and Temple, 1987a)

Andean condors travel as much as 200 miles per day at extremely high altitude in search for food. The nesting territory was described as being 1 kilometer surrounding the nest and this area was defended vigorously from other condors as well as potential nest predators. Andean condors are not described as especially territorial except when it comes to defending their nest. (Fisher, 1942; Lambertucci and Mastrantuoni, 2008)

Andean condors rely on their sense of sight to detect and locate carrion from thousands of feet in the air. They also may use visual cues from smaller vultures, which use smell to locate food.

Both sexes have the ability to change the color of the bare skin on their neck and face in association with mood. This is used for communication between individuals and males also use this for displays during mating season. Males use face and neck flushing (yellow) as part of their visual courtship displays. Andean condors also use clicking and hissing for communication but they lack a syrinx which is needed to produce more complicated bird calls.

Like all birds, Andean condors perceive their environments through visual, auditory, tactile and chemical stimuli. (Wallace and Temple, 1987a; Whitston and Whitston, 1969)

Andean condors may form mutualistic relationships with smaller turkey vultures (Cathartes aura) and black vultures (Coragyps atratus), which forage by smell whereas Andean condors forages by sight. Larger Andean condors are much better adapted at tearing into the tough hide of a fresh kill. The smaller vultures benefit from the labors of the condor and feed on what is left of the newly opened carcass. Within the last century or so there has been an ecological shift in food availability across much of the Andean condors' range as native megafauna species (Llamas, alpacas, rheas, guanacos, and armadillos) are widely being displaced by domesticated animals (cows, horses, sheep, and goats) as well as those introduced for sport hunting (rabbits, foxes, wild boars, and red deer). Andean condors also eat carcasses of whales and other large marine mammals in coastal regions.

Andean condors are primarily scavengers but have been observed to do some hunting of marmots, birds and rabbits. Andean condors lack well developed hunting techniques but may chase and grab at live prey, in which case they begin feeding before the animal is dead. Andean condors hold prey by standing on it, as they lack the strong grasping feet found in most hunting raptors.

When approaching a fresh carcass, Andean condors often start opening the animal near the anus and progress toward the head. One of the first things eaten is usually the liver, followed by the muscle. No significant attempt to open the skulls and eat the brain has been observed.

In the northern reaches of their range, where Andean condors are in sharp population decline, food availability is a problem. One study suggested that this lack of food may increase the condors tendency to forage on road kill which presents a threat of being hit by a passing car. (Gailey and Bolwig, 1973; Lambertucci, et al., 2009; Speziale, et al., 2008; Wallace and Temple, 1987a)

Healthy adult condors have no known natural predators. Young chicks may fall victim to large birds of prey or to foxes if the nest is accessible to flightless predators. Eggs may also be lost to predation.

Andean condors nest on high, inaccessible cliff ledges where available but sometimes nest in areas that are more accessible by land. They are known to aggressively display and actively defend the nest site from potential predators, including zoo keepers. (Lambertucci and Mastrantuoni, 2008; Whitston and Whitston, 1969)

Andean condors are some of the largest and most successful avian scavengers on the planet and they serve an important role in the consumption of carrion to help prevent the spread of disease in an ecosystem.

Smaller vultures may have a mutualistic relationship with large Andean condors where the smaller birds locate carrion and provide passive visual cues to the high soaring Andean condors that food is nearby. The larger, more powerful condors usually arrive last to the group and opens up the carcass. This provides the smaller vultures with access to areas that were too tough to exploit on their own. The arrival of Andean condors was observed to cause visible "excitement" among the smaller vultures. Condors' activity of opening up a carcass has been observed to start a "feeding frenzy" among smaller scavengers, in which all normal dominance hierarchies are temporarily ignored. (Wallace and Temple, 1987a)

Andean condors have been extremely important as a cultural symbol in the Andes mountains of south America for thousands of years. In the ancient Inca culture of Peru the condor represents one of the three realms of existence, the heavens; while the Jaguar represents the earth and the snake the underworld. These three cultural references appear all over Inca society, including in their architecture. The site of Machu Picchu, which was a royal vacation home, is built in the shape of a condor if viewed from the top of a nearby mountain. There is also a massive stone altar in the site that is shaped like a huge condor with wings spread high.

Andean condors also serve essential roles for humans as important carrion feeders that help limit the spread of disease.

Andean condors are one of the world’s largest flying birds and thus their survival in the native habitat is important for ecotourism in South America. Andean condors are also often found in zoos, being a popular animal to exhibit due to their status. They were also an important learning resource for zookeepers to gain experience with the challenges of captive breeding large condors that was essential to the conservation of critically endangered California condors. (Brown and Mitchell, 2000; Wallace and Temple, 1987b; Whitston and Whitston, 1969)

Andean condors tend to feed on large dead animals and occasionally will hunt sick and injured megafauna. Much of the local megafauna in the Andean highlands has been ecologically replaced by domesticated range species such as lamas, cows, horses, sheep, and goats which now constitute a large part of condors' diets. This has led some farmers and ranchers to see them as pest species that harass their livestock. Poisoning was not uncommon over the last hundred years but is now becoming less common due to an increase in public awareness and appreciation of Andean condors as symbols of the region. (Lambertucci and Mastrantuoni, 2008)

Andean condors are listed as 'Near Threatened' on the IUCN Red List as they have faced significant population declines in recent years. Threats to Andean condors include habitat loss, lead ammunition ingestion, and persecution by farmers. Even after captive breeding and reintroduction programs, the slow reproduction rate (once every 2 to 3 years) of these birds is slowing population recovery.

Past conservation concerns had to do with the use of lead ammunition for hunting, because condors' digestive systems are harsh enough to absorb large quantities of the lead if ingested from scavenged gunshot kills. There has been much effort to end the use of lead ammunition within the range of Andean condors, but concern still exists.

The ecological replacement of many of Andean condors' native food sources by domestic animals may have unforeseen long term effects on their survival. (Lambertucci, et al., 2009)