Mexico's First California Condor Chick Gone

May 25, 2007

Biologists with the California Condor Recovery Program, checking on a 1-month-old California condor chick, the first produced in Mexico in at least 100 years, found the nest in the Sierra de San Pedro Mártir National Park empty on May 23.

Mike Wallace, Ph.D., scientist with the Zoological Society of San Diego’s center for Conservation and Research for Endangered Species (CRES), said the parents, condors 217 and 261, were seen feeding together three days before he found the chick missing. Not until the chick is 50 days old will condor parents leave a live chick alone. Until then, the parents take turns caring for it while one adult feeds.

“The parents were behaving accordingly, protecting the chick,” said Dr. Wallace, who is also the California Condor Recovery Program team leader. “There was no indication that there was a problem until five days ago when both birds were observed away from the nest together. The loss of this chick is not unexpected in a new pair as first-time parents rarely succeed in raising their first chick. It is a learning experience for them and us.”

Wallace has two theories to the disappearance. Predation from a golden eagle is likely as the condors took over a former golden eagle nest and this species was still seen in the area by biologists. Dr. Wallace found a parasitic insect infestation in the nest that could have resulted in the death of the chick, causing the parents or other scavengers to dispose of the carcass.

“There may be a good adaptive reason for condors to normally use sandy bottom substrate instead of stick nests that may better harbor insect parasites and insect eggs,” Dr. Wallace said.

Unfortunately, the biologist found no traces of the chick in the nest or in the area. The last documented wild California condor in Mexico was spotted in the late 1930s. The California Condor Recovery Program joined forces with the Mexican government to reintroduce this species to its native habitat in the pristine mountain range where 11 condors, including this breeding pair, now fly free.

“This unfortunate event demonstrates to us that there is still much to learn about the biology and interactions of this species in this new and well-preserved habitat in Baja California,” said Eduardo Peters, biologist for the Mexican Instituto Nacional de Ecología (INE). “We hope next year the project will be more successful as there is a possibility of having two more pairs at the reproductive stage.”