By Katherine Shaver
Tuesday, December 28, 2010; 7:58 PM
Two cheetah cubs who made their media debut Tuesday have already helped bolster the endangered animal's population in captivity, becoming the first born at the Smithsonian's research center in Northern Virginia and among the first to be raised by the same mother as non-siblings.
The cubs - born 10 days apart in December at the Smithsonian Conservation Biology Institute in Front Royal - are being followed closely by cheetah experts because they are the sixth case of "cross-fostering" in North America since 1995, said Adrienne Crosier, the institute's cheetah biologist.
Zazi, the 9-year-old mother to a 2-week-old unnamed female cub, has adopted a 3-week-old male cub born to a 5-year-old mother named Amani. Zazi has nursed and tended to the male cub, who has yet to be named, since Dec. 21, when the staff placed him with her because he had little chance of surviving as a single cub with his own mother, Crosier said.
Cheetahs usually have litters of three or four cubs. A single cub dies in the wild because it can't stimulate its mother's milk production enough to nurse exclusively for the two months before it begins to eat meat, Crosier said. Single cubs in captivity can be bottle-fed with animal formula, she said, but they are far more likely to breed as adults if they are raised by cheetahs rather than humans.
When the male cub was born alone Dec. 6, Crosier said, she and three other staff members bottle-fed him and kept him warm in an incubator at the veterinary clinic, knowing that Zazi was due to give birth the next week and might be willing to take him on. Three other cheetah facilities - two in Texas and one in Florida - had successfully carried out such cross-fosterings five times since 1995, Crosier said, but it had never been attempted in the Washington area.
When Zazi also gave birth to a single cub Dec. 16, the arrangement turned out to benefit both babies, as two cubs would better stimulate her milk production.
"She has the perfect temperament for this," Crosier said of Zazi, who had previously raised five cubs born at the National Zoo in 2005. "She's a very calm, resilient cat."
While Zazi was in her yard eating Dec. 21, the staff workers made their move. Crosier and lead cheetah keeper Lacey Braun had already rubbed the male cub, then 2 weeks old, with wood shavings from the 80-square-foot "nest box" where Zazi was tending to her own cub. They then rubbed the male cub against Zazi's female cub to make him smell even more familiar and left the two in the nest box together.
When Zazi went back inside, she picked up the male cub with her mouth, set him back down, and immediately began to lick and groom him, as Crosier and other staffers watched from afar via mounted video cameras. About an hour later, Zazi nursed both cubs and has since treated both as her own, Crosier said.
"She was even more wonderful than we expected," she said.
Researchers don't know if such cross-fostering occurs in the wild, Crosier said. She said that Zazi will raise both cubs for about 18 months and that Amani likely will never recognize the male cub as her own. Amani seemed to look for her cub for a couple days after the staff removed him for bottle feeding but has behaved normally since, Crosier said.
Both cubs likely will end up at one of the six other cheetah breeding centers in North America. The Front Royal facility now has nine cheetahs, including the two cubs, and the National Zoo has four.
The cubs are the 32nd and 33rd cheetahs in North America to survive birth in 2010, almost triple the 12 born in 2009, Crosier said. With an estimated 7,500 to 10,000 left in the wild, cheetahs are considered "vulnerable to extinction," Crosier said.