A pair of California condors at the San Diego Wild Animal Park have commenced what curators say is an elaborate and prolonged courtship, raising hopes that they might produce next spring the first condor chick conceived and hatched in captivity.
The pair is one of only three pairs believed capable of breeding among the 27 California condors known to be living. All 27 have been captured and are being kept at the Wild Animal Park and the Los Angeles Zoo as part of a controversial captive breeding program.
"Hopefully, this is a prelude to breeding the condors in captivity in the spring," Bill Toone, the park's curator of birds, said Tuesday. ". . . To have birds again in the wild is going to depend very much on the reproductive capabilities of the birds in the zoo."
The two condors--a 7-year-old male designated Adult Condor 4, or AC-4, and an adult female of unknown age designated UN-1, or Unknown 1--began sporadic "courtship behaviors" about a month ago and now appear to be courting about five times a day, Toone said.
During courtship, the male lands near the female, arches its neck, drops its head and spreads its wings as though "every muscle is tense," Toone said. He then drops his tail, approaches the female with a rocking motion, and circles her in the same posture.
Toone said the female might then "neck" with the male, rubbing her neck and head against his. After several minutes, the process usually ends abruptly with the female snapping at the male--an outcome that should become less common over the next few months.
The birds have also begun "investigating the nest area together"--a behavior common in the wild as breeding season approaches. Toone said keepers have observed "more and more traffic in and out of the nest box and roost area" in the condors' enclosure at the park.
"He'll have to keep warming her up for several months," Toone said. If there is mating, UN-1 might be expected to lay a single egg within several weeks.
Breeding program officials have not decided whether to "manipulate" the birds' breeding--that is, remove a first egg in order to encourage more. That decision will be made in conjunction with state and federal officials involved in protecting endangered species.
Toone said past experience in the wild indicates that it might be possible to get as many as three eggs in a single season through manipulation.
'There Is Every Hope'
"This is real encouraging and I have every hope that it's going to pan out with eggs and chicks in the coming year," Toone said. "There is every hope and there is every chance. Yeah, this is what it takes."
Toone said there have been few such encouraging instances in the past.
Topa Topa, an adult male in captivity in Los Angeles, has exhibited courtship behaviors in the past, Toone said. "The only disappointing thing about Topa is he directs his behaviors to butterflies, rocks, keepers and poles, as well as other condors," he added.
He said younger condors have also tried courtship--but before reaching sexual maturity at age 7 or 8. He said most of the condors in the program are relatively young, the products of the hatching in captivity of eggs brought in from the wild.
Thirteen of the 27 birds known to be living were hatched in captivity after scientists removed eggs from nests in the wild. Another three were hatched in the wild and removed in infancy. The remaining 11 birds were captured by scientists.
"In 1983, the hatching of Sisquoc was a landmark event," Toone said, referring to the first wild egg successfully hatched in captivity. "It had been said for years that it couldn't be done. . . . That laid that myth to rest."
Toone said he believes the successful breeding of AC-4 and UN-1 would shatter what he called another myth--that condors cannot be bred in captivity. He said it has not been done so far because there have been so few mature condor pairs.
The final challenge, Toone said, will be to prove that condors born and raised in captivity can be reintroduced and survive in the wild. If breeding succeeds this spring, that reintroduction could begin as early as 1990 to 1993, Toone said.