Biology | PCCA

BIOLOGY

The Andean Condor (Vultur gryphus), is the largest flying bird in the world, belonging to the Falconiformes order and to the Cathartidae family.

It measures 1,20mts in height with a wingspan of 3mts and a weight of up to 12kgs (Kasielke,et al 1990, Jacome, 1995).
Regarding the colour of their feathers, the moulting is linked to adulthood and it starts when they are around three to four years old, when they begin to change the colour of ruff feathers around their necks from grey into white, which is the characteristics colour in adults.
The changes occur gradually and the ochre plumage of juvenile’s changes to grey and defines their final black and white colour when they are six to eight years old.
Males have a fleshy crest (caruncle) and coffee colour iris, while the females lack the crest and their iris is red in colour (when they reach sexual maturity).
Like all vultures their heads and necks are hairless, which among other functions, helps the animal keep hygiene while eating carrion. These birds do not have prehensile feet, their nails are more like blunt claws but have robust legs with
powerful toes. (Parera, A; 1997).
Their strong and flexible bill allows them to open the skin of large dead animals, so that they and other
smaller necrophagous species can reach the food (Cuesta, 2000).
The colour of the bill is also an indication of their age, changing gradually from black to white. Their most important function in nature, amongst others, is that they clean up the environment from dead animals, which could spread dangerous diseases (Wallace, et al 1985).
The condor can spend several days without eating, there are records of being able to store up to 4 kgs of meat pulp in their crop for up to one week. When finding food the condor does not descend immediately, as it is difficult for them to take off once on the ground, especially after eating. It is for this reason that they are particularly careful before landing and ensure there is no danger around. The condors are gregarious birds and they have a strict hierarchy where adult males are dominant, followed by females of the same age, young adults and then juveniles. There seems to exist a social learning from this hierarchy when it comes to feeding.

The Andean Condor is a K-strategists species. This means they have a long-life expectancy, living 70 years or more, they are slow to attain sexual maturity, share rearing of chicks and have a long parental care period.
Sexual maturity occurs between 8 to 9 years old (Temple, et al 1989; Jácome, 1994). The Condor is a monogamous animal. It uses cliff platforms or ledges to spend the night and caves or protected cavities to nest. The couple lay only one egg on the sand or gravel of the ground, without building any structure or nest. Both incubate, rear and have a long-term care (period) for their chick. This long reproductive cycle indicates that one couple rear only one chick every 2 to 3 years.
In view of the low reproduction rate, for the population of condors to remain stable, it needs the same low mortality rate. Therefore, the mortality caused by humans is of great importance and has a great impact on the natural populations.