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ON THE SOUTH RIM of Grand Canyon National Park, Arizona, high in a band of Redwall Limestone, a six-month-old California condor chick dances on the edge of a precipice overlooking the Colorado River. In March 2003, biologists first suspected that condors #123 and #127 were incubating an egg. (California condor studbook identification numbers signify the bird’s parentage, genetic integrity, and diversity.) Although biologists and Nestwatch volunteers had continually monitored the parents’ activity and behavior since suspecting there was an egg, the chick could not be confirmed until it moved to the entrance of the cave at five months of age. The only way to see the nest site, which rests 800 feet (244 m) above the ground, is to take an arduous 12-mile hike into the canyon. Park biologists observed the chick stretching out its long wings and flapping without lifting off, in preparation for the day in late October or early November when it would step beyond its rocky nursery.
Over the past 10 years, condors have been restored to several locations in California and Arizona, and the California population of condors hatched one wild chick in 2003. But during a nest site cleanup, the bird appeared emaciated and stunted and had to be emergency airlifted from its nest cave and later euthanized. The condor’s parents had brought trash—glass, metal conductors, and bottle caps—into the site, apparently simulating the feeding of calcium supplements, which are a requirement of the condor diet. However, a chick cannot pass the foreign objects through its system; respiratory damage occurred, resulting in pneumonia.
The dietary necessity of calcium supplements, which has persisted for thousands of years, was revealed during analyses of nest contents from an earlier failed nest site at Grand Canyon. Investigators discovered calcium bone fragments brought in by adult condors from a much earlier period: Pleistocene remains of horse, bison, and musk ox. These particles were found in the nest in a layer beneath this year’s collection, which also included the bottle caps and glass.
Biologists participating in the multiagency cooperative effort closely monitored feather development, crop size, and activity levels of Grand Canyon chick #305. As it neared fledging from its lofty perch, biologists remained cautiously optimistic.
The monumental flight finally occurred at 1:30 p.m. on November 5, 2003. The chick jumped from the cave, looked for a nearby landing perch, and realizing there was none, ungracefully circled and landed about 600 feet (183 m) below the cave.
Having a condor hatch and fledge in the wild—something that has not happened anywhere since 1984 and not in the Grand Canyon for at least 100 years—is indeed a measure of success. However, wild rearing of the chick and protection from human-caused and environmental contaminants ultimately will determine long-term preservation of this species, which has been brought back from the brink of extinction.
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