DC zoo celebrates birth of panda twins

WASHINGTON - What could be better than one panda cub? TWO.

The National Zoo's female giant panda, Mei Xiang, gave birth to a baby panda cub on Saturday afternoon-- and then, a few hours later, she had another one! The zoo says the first cub was born at 5:35 p.m. and the second came at 10:07 p.m. After the second one was born, the zoo's panda team retrieved one of the pandas, and placed it in a incubator. The zoo keepers say it appears that the first one retrieved was the first one born. On Sunday morning, the panda team swapped cubs.

According to the zoo, giant pandas give birth to twins 50 percent of the time, and this only marks the third time that a giant panda living in the U.S. has had twins.

So far, Mei Xiang appears to be doing well, panda keepers at the zoo say. She has one cub in her possession while the other is in an incubator, and the panda team will continue to alternatively swap out the cubs so she can spend time with one while the other is being bottle fed and staying warm in the incubator.

When the first panda cub was born, Mei Xiang reacted by picking the cub up. The new cubs' sex won't be determined until a later date, and the zoo also isn't sure whether there will be a contest held to name them.

The zoo says when they saw Mei Xiang's water break at 4:32 p.m., they started to prepare for her to give birth. At that point, she was already having contractions.

The zoo expects Mei Xiang to spend almost all of her time in her den for the next two weeks with her newborn cubs. The David M. Rubenstein Family Giant Panda Habitat has been closed to the public since Aug. 20, and will remain closed until further notice to provide quiet for Mei and her cubs. Both will continue to be visible on the panda cams. Visitors can also see Tian Tian and two-year-old Bao Bao (whose birthday is actually tomorrow) in their outdoor habitat and on the panda cam.

The zoo's panda cams were overloaded by heavy traffic from those around the world wanting to watch the birth live. Users were advised to refresh their browser, or download the National Zoo's mobile app to watch live without interruption.

Mei Xiang gave birth to Tai Shan, her first cub, in 2005, and her second cub, Bao Bao, turns 2 on Sunday. Mei Xiang also had a stillborn cub in 2013, and in 2012, she gave birth to a cub that died six days after it was born because its lungs weren't fully developed.

The National Zoo tweeted Saturday that they were hoping for a healthy cub.

The news that Mei Xiang might be pregnant came earlier this week, after an ultrasound was performed on Wednesday. At that time, the zoo estimated the fetus was about 4 centimeters, and that Mei Xiang could give birth next week, or in early September.

Scientists artificially inseminated Mei Xiang on April 26 and 27. In July, the zoo said her hormone levels were rising and she began exhibiting behaviors consistent with pregnancy or a pseudopregnancy. Mei Xiang has had five pseudo-pregnancies between 2007 and 2012.