A rare white-naped crane has hatched at the Smithsonian’s National Zoo Conservation and Research Center in Front Royal, Va. on May 23. The two-week-old female chick is the most genetically important hatchling in the North American White-Naped Crane Species Survival Program. The population has suffered from a lack of female hatchlings over the past few years, putting the population at risk of stagnation without adequate females to produce more offspring. This hatching gives a much needed boost to the captive population of the endangered species.
The chick’s mother was sent to the CRC earlier this year to breed. Neither the 20-year-old female crane nor her new mate had ever produced offspring and the CRC’s bird staff have had great success in the past in breeding previously unsuccessful pairs of cranes. The Species Survival Plan—a cooperative breeding program among zoos that pairs animals in order to maintain genetically healthy populations—had determined from the birds’ genetics that they were the perfect match.
At first the birds seemed compatible, but when breeding season arrived, instead of displaying the elaborate courtship behavior that cranes exhibit before mating, they fought. Keepers suspect that the female crane imprinted on humans at an early age, causing her to exhibit inappropriate behavior and inciting aggression from the male.
Since natural mating was not possible, staff decided to perform artificial insemination. Bird keeper Chris Crowe slowly earned the female crane’s trust—playing with her, sitting with her, adapting her to his presence and touch—and was eventually able to successfully artificially inseminate her without using restraint or anesthesia.
A few weeks later the female laid a fertile egg. But staff still had an additional obstacle to surmount. The breeding program currently contains more than enough male cranes and greatly needs female offspring to prevent the population from stagnating. Hence, they needed to determine the sex of a chick before it hatched. Staff developed a technique that allows them to penetrate the eggshell and extract blood without killing the embryo or introducing microorganisms that would later kill the embryo. Genetic testing from the blood sample revealed the chick inside the shell was a female. She hatched successfully and is now being raised by the parents of her biological father.
White-naped cranes are large birds that typically stand 4 feet high and weigh about 12 pounds. They are mostly dark-grey with a white hind neck. Destruction of its native wetland habitat in northeast China has dramatically decreased white-naped crane populations in the wild to an estimated 5,000. The CRC currently has 10 cranes; there are an additional 60 animals in the White-Naped Crane Species Survival Program.