Thursday, July 24, 2008

Andean Condors in Decline

As I have written before on this blog, California condors are not the only condors of the Western Hemisphere that are in trouble. The Andean condors of South America are also in decline. Though they are still common in Chile and Argentina, they are endangered in the northern part of their range – Peru, Bolivia, Ecuador, Colombia, and Venezuela. The population in the latter three countries is 150 condors combined.

One aspect of the decline seems to be the expansion of American-style industrial agriculture.

In nature, Andean condors survive off the remains of deer, guanaco — a llama-like mammal — and other animals that predators such as pumas leave behind.

Such food supplies fell sharply throughout the 20th century in countries such as Chile when people settled farther out into wild lands and replaced the native fauna with cattle, sheep and other livestock.

The Andean condors adapted by eating wounded or dead livestock left out in the open, usually by accident. Some condors flew hundreds of miles from their mountain homes to feed on dead seals on the Pacific coast, often making the round trip in a single day.

But that domesticated food source began dwindling as more ranchers raised livestock in feed lots, which cut back on the number of wounded or dead animals left in the open. On top of that, many ranchers have hunted down condors, mistaking them for predators capable of carrying off livestock.
So far the techniques used to regrow the California condor population have not worked for rebuilding the northern population of Andean condors. Captive-bred Andean condors failed to reproduce after being released in Colombia. Further south, where the decline has been less severe, conservationists in Chile and Argentina have been rehabilitating sick and injured condors and releasing them back into the wild.