WASHINGTON — For the first time, four giant pandas are living at the National Zoo in Washington after the zoo's adult female gave birth to a cub on Saturday.
Zoo director Dennis Kelly said at a news conference that he was "so happy, so pleased, so excited" to confirm that Mei Xiang gave birth to the cub at 5:35 p.m. If the cub survives, it would be the 17-year-old panda's third surviving offspring.
Mei Xiang's first cub, Tai Shan, was born in 2005 and returned to China in 2010. Her second cub, Bao Bao, turns 2-years-old on Sunday and still lives at the zoo. In addition to Bao Bao, Mei Xiang and the new cub, the zoo is also home to an adult male panda named Tian Tian.
Keepers will be watching the newest cub closely. Pink, hairless and blind, newborn cubs weigh 3 to 5 ounces and are about the size of a stick of butter.
Kelly said this is "still a very fragile time for the cub."
"We're very excited, but we're very cautious," he said, noting that in 2012, Mei Xiang gave birth to a cub that died after just six days. Its lungs hadn't fully developed.
Still, the zoo's chief veterinarian, Don Neiffer, says the newest cub has shown "all signs of being healthy and happy." Keepers have heard it squeal and grunt. Neiffer said that he doesn't know when zoo staff will examine the cub and that at this point they won't interfere unless they get concerned, for example, if the cub looks weak or stops making noise.
Even if the new cub is healthy, panda fans shouldn't expect to see it in person for a while. After Bao Bao was born in 2013, it was about five months before she made her public debut. Fans who want to see the newest panda will have to try to catch a glimpse of it on the zoo's online panda cameras. Though the zoo's camera-viewing site can host about 850 viewers at a time, spokeswoman Pamela Baker-Masson says the site has been overloaded with people trying to watch. Fans can also download a zoo app to view the cameras.
The public also won't learn immediately whether the cub is male or female or whether the zoo's male panda, Tian Tian, is the cub's father. Mei Xiang was artificially inseminated with sperm from Tian Tian and a panda named Hui Hui from Wolong, China, who was determined to be one of the best genetic matches.
Laurie Thompson, a giant panda biologist at the zoo, said once keepers do have a chance to examine the cub they will take a swab of saliva from its mouth which will be used to determine its gender and paternity.
For now, the zoo will be watching the cub round-the-clock. They'll also be on the lookout for a possible second cub. In 2013, when Mei Xiang gave birth to Bao Bao, she also gave birth to a stillborn cub. Neiffer, the zoo's chief veterinarian, said Saturday that during an ultrasound earlier in the week he did see "two areas that made me excited." But he said "if there was something else it did not appear to be formed."
The National Zoo is one of only four zoos nationwide to have pandas, which are on loan from China. But the Washington pandas have a history that makes them closely watched.
The zoo's first pair of pandas, Ling-Ling and Hsing-Hsing, were a gift from China following President Richard M. Nixon's historic 1972 visit to the country. The pair had five cubs while living at the zoo but none survived.
The zoo's current pandas, Mei Xiang and Tian Tian, the parents of both Bao Bao and Tai Shan, arrived in 2000. The pandas belong to China as do any cubs they have.
The cub's birth isn't the only event being celebrated at the zoo this weekend. For Bao Bao's second birthday Sunday she will get a cake made out of ice with the number "2" on top. She will stay at the zoo until she is 4 years old when she will return to China.