SAN DIEGO. Endangered California condors could have a “virgin birth”, according to a study published Thursday.
Researchers at the San Diego Zoo Wildlife Alliance said genetic testing confirmed that the two male chicks, hatched in 2001 and 2009 from unfertilized eggs, were relatives of their mothers. None of them were associated with a man.
The study was published Thursday in the Journal of Heredity. This is the first report of asexual reproduction in California condors, although parthenogenesis can occur in other species as well, from sharks to honey bees to Komodo dragons.
But in birds, this usually only happens when the females do not have access to the males. In this case, each condor mother had previously mated with males, producing 34 chicks, and each was kept with a fertile male while they were producing eggs through parthenogenesis.
The researchers said that, in their opinion, this is the first case of asexual reproduction in any species of bird, when the female had access to a mate.
“These results now raise questions about whether this might be happening unnoticed in other species,” said Oliver Ryder, study co-author and director of conservation genetics at the San Diego Zoo’s Wildlife Alliance.
The nonprofit alliance operates the San Diego Zoo and Safari Park and is involved in the California condor breeding program that has helped giant vultures return from near extinction.
With a wingspan of 10 feet (3 meters), California condors are the largest flying birds in North America. They once spread throughout the West Coast. But only 22 of them survived in the 1980s, when the US government captured them and placed them in zoos for captive breeding. About 160 individuals were bred at the San Diego Zoo and Safari Park.
There are currently over 500 California condors, including over 300 released into the wild in California, Arizona, Utah, and Mexico.
Asexual reproduction was discovered several years ago through extensive testing of genetic material collected over decades from condors, both living and dead, in breeding programs and in the wild.
“Among 467 male Californian condors tested in the paternity analysis, not a single male was recognized as a potential father,” the two birds said.
California condors can live up to 60 years, but both males were sickly. One was less than two years old when he died, and the other was less than eight years old.
