California condors are one of the most impressive American birds, but not because of their beautiful song; they have no syrinx and can only vocalize over short distances with grunts and hisses. Neither can they boast beautiful coloration as they transition from their juvenile gray-brown plumage to a black and white adult coloration by six years of age. What strikes most people who have encountered them in the wild is their impressive size and beauty in flight. Weighing in at 18 to 26 pounds and standing nearly a yard tall they dwarf other “large” avian species like golden eagles and turkey vultures that often compete for their large animal carrion such as deer, elk, cows and horses. Casting a nine and a half foot shadow, the sight, and sound (if close enough) of a soaring condor leaves an indelible memory on any high altitude hiker!

What continues my 30-year fascination with this highly endangered species is its intelligence and social behavior. Like primates or social carnivores, each bird has a specific ranking within the pecking order of the local population. This social status is based on age, experience, sex and physical attributes like weight and physical ability. Condors are all about conserving energy and an ordered social hierarchy reduces the amount of time individuals spend in altercations over resources. While continuous, mild, non-violent displacements occur throughout the day by dominant birds towards subordinates over resources such as food, perches and even air space, higher intensity aggression is usually seen only between two birds of nearly the same rank. Since every two to four days the birds return to the feeding sites, we can tally the winners and losers of their interactions and assess their hierarchal relationships from camouflaged blinds as they feed. By better understanding the social rules under which this gregarious species functions we gain predictability and can fine tune our captive rearing conditions and management for better behavioral results, and hopefully survivorship in released condors.

During our efforts to re-establish captive bred condors in Baja California, Mexico, that we have been conducting since 2002, I have had a chance to get a closer look at these social workings. What determines a bird’s status in the first place involves the parameters mentioned above, yet an individual’s social position is not cast in stone. So a big question is what are the social rules and environmental conditions that allow a bird to increase (or decrease) its social status?

To establish a condor population in an area they once inhabited we, in effect, train them to a site with behavioral management, food and topographic features that will enhance their ability to become competent flyers and learn how to function as condors in their new “wild” environment. Since they are completely dependent on us for food and water, as they would be with their parents for an extended period of months after fledging, we provide large animal carcasses in and immediately outside the release pen where they can watch the smaller scavengers and previously released condors feed.

Condors rely heavily on each other, particularly more experienced birds to consistently find food. Not having the olfactory ability of the smaller turkey vulture, condors use observation of the activities and behavior of the more numerous smaller scavengers as well as other condors to find a carcass. Historically they also had the benefit of learning the tried and true foraging traditions that developed over centuries in their local population that would indicate where food was likely to show up in any given period of the year within their potential foraging distance of several hundred miles. As expected, it is taking decades for our released condors to develop a functional food finding tradition in areas we are attempting to re-establish them. To manage the process we subsidize the inexperienced population with carrion proffered at various times and locations in their environment thus encouraging natural foraging.

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