Officials at the San Diego Wild Animal Park confirmed Friday that the third egg laid recently by California condors there is infertile.
“We confirmed through candling this afternoon that the third egg is infertile,” said Tom Hanscom, spokesman at the park in Escondido. Candling involves holding the egg up to high-intensity light to see if an embryo is growing inside.
The birds are part of a captive breeding program begun in 1980 to try to replenish the near-extinct species for release into the wild. There are 28 known California condors remaining, all of them in captivity and evenly divided between the Los Angeles Zoo and the Wild Animal Park.
The infertile egg, laid by Almiyi, whose partner is called Paxa, was the third egg to be laid within a week during February. Altogether, four eggs have been laid by captive condors. Officials had feared that the egg would be infertile because of the sexual immaturity of the birds. Another egg produced by condors Cuyama and Cachuma at the Los Angeles Zoo is also infertile.
“The (Escondido) egg was produced by an immature pair. It happens pretty often. Our knowledge of California condors is weak at best, but, in all likelihood, all of them are capable of producing infertile eggs in the first attempt,” Hanscom said. Condors reach sexual maturity at about age 7.
“It’s a matter of technique as well as physiology,” Hanscom said. “They had not been seen in what would be regarded as complete copulation. It comes with practice. I know that sounds simplistic, but it’s an acrobatic feat if nothing else.”
The mating of condors requires balancing by both the female and the male, he said. “It’s fairly active coupling, and there is a degree of acrobatic skill involved. They haven’t tried it that many times.
“I’m sure they will continue trying and they will eventually get it right. If this pair continues to breed . . . we could see an egg at the end of this month,” Hanscom said.
Mating season for the condors begins in February and can last into April, he said. “We’ve seen eggs produced by condors as late as early April, and condors are capable of regenerating an egg 30 days after the first.”
An egg laid by UN1 and AC4, the condors who produced the chick Molloko from the first egg laid in captivity last March, is “developing well,” Hanscom said, and the couple are giving every indication they are taking steps to lay another.
“They fought the day the egg was laid, and continued to fight into the afternoon,,” he said. “But the day after, they were observed mating again.”