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Frequently Asked Questions About Our Panda Cub

When will the cub be on exhibit?

The David M. Rubenstein Family Giant Panda Habitat will reopen to the public when the cub is about four months old, though the exact timing will depend on Mei Xiang and the cub.

Is the panda cub a male or female?

Our giant panda cub is a male! Scientists from the Smithsonian Conservation Biology Institute’s Center for Conservation Genomics used DNA analysis to determine the sex of the cub. They obtained the DNA from a gentle cheek swab at a veterinary exam.

Will this cub go to China?

Yes, the cub will go to China after four years.

When will the cub be named?

We’re just taking things one day at a time right now. We’ll announce plans for a name in the future.

Why do you need a DNA test to determine the cub’s sex?

External genitalia in bears doesn’t develop until the bear is several months old. The best, and most reliable, way to determine a bear cub’s sex is through DNA analysis. We were able to determine that the newborn cub is a male.

Why is Mei Xiang in such a small space?

In the wild, bears—including giant pandas—give birth in small dens. In China's Wolong Reserve, pandas make their dens in large hollow conifer trees, with a diameter of about three feet. Where there aren’t any trees, pandas den in caves with a little bedding of twigs. They stay in these dens for about the cub’s first 100 days.

We strive to recreate these surroundings for Mei Xiang. She always has access to her larger enclosures, though for the first few months of the cub's life she will spend the vast majority of her time in the den with him. She will occasionally venture out to eat, drink, urinate and defecate. Those trips will become increasingly longer as the cub grows. In January of 2013, in anticipation of the breeding season, we rearranged Mei Xiang’s den. We shifted the angle of the bars, so that keepers have more direct access to Mei Xiang and her cub while they are resting in the nest area. The old bars were recycled, making the renovations not only a little greener, but also a little less overwhelming for Mei Xiang. It was as if the “furniture” was simply rearranged one day.

Why are the lights always on in the den? Why is the cam sometimes in color and sometimes in black and white?

It is usually dark in Mei's den, as it would be in a wild bear's den, but the cams have infared and low-light capabilities, which allows her and the cub to be visible to cam viewers. This is also why the cam usually looks black and white. When the keepers turn on the lights, the cam shows up in color—except for the bears, of course, who are always black and white.

Why isn't Mei Xiang eating?

When bears give birth in the wild, the mothers spend several months denned up with their cubs. Their focus during this time is nurturing and protecting their cubs, rather than eating. Scientists have observed giant panda mothers in the wild go as long as a month without eating or drinking. Like other bears, pandas seem to go through a metabolic shift during the summer months, when their food intake drops up to 75 percent. This coincides with when pandas den and produce cubs, like other bear species. One difference to note is that other bears fast for several months during hibernation.

Why do the panda cams go off periodically?

The cams are turned off periodically when keepers enter the den to assess the cub and Mei Xiang.

Why is Mei Xiang licking the cub?

New born giant panda cubs are born very tiny and delicate. When Mei Xiang licks the cub she is stimulating him to urinate and defecate. Cubs are unable to urinate and defecate on their own in the first weeks of life.

Where is the cub?

Mei Xiang keeps her cub tucked under her arm, or under her chin much of the time. He is unable to regulate his own body temperature, so Mei Xiang cradles him closely to her body to keep him warm. She moves him by picking him up in her mouth.

Why is the cub squealing?

The cub squeals when it wants to nurse or be repositioned. Regular loud squeals are signs of a healthy cub.

Why is Mei Xiang breathing heavily on the cub?

Sometimes it appears as though Mei Xiang is breathing heavily. She is breathing on her cub to keep him in a warm and humid environment.

Who is the cub's father?

Scientists from the Smithsonian Conservation Biology Institute's Center for Conservation Genomics used DNA analysis to determine the sire of the cub. It showed that Tian Tian is the sire.

SCBI scientists artificially inseminated Mei Xiang April 26 and 27 with fresh semen from Tian Tian, and frozen then thawed semen from Hui Hui (h-WEI h-WEI). Hui Hui lives in China, but was one of the best genetic matches for Mei Xiang.

Why did you use sperm from both Tian Tian and Hui Hui?

In China, it is standard practice to use sperm from more than one male when artificially inseminating a female. This increases the chances of fertilization and viable embryos. Hui Hui a 10 year-old living in China was one of the best genetic matches for Mei Xiang. An SCBI scientist and Rubenstein Fellow, Caitlin Burrell, brought a frozen sample of Hui Hui’s semen back from China with her in April. It was placed in SCBI's cryopreservation bank at the National Zoo.

Will Tian Tian meet the cub?

Male pandas are not involved in the care of their cubs. Fathers and cubs may never encounter each other in the wild.

Will Bao Bao ever meet the cub?

No. In the wild giant pandas are solitary and separate from their mothers around 18 months old. We strive to mimic those conditions at the Zoo.

How did you determine the window for a possible birth?

The panda team prepared for a panda cub birth based on behaviors they saw, hormones they monitored, and ultrasounds. Smithsonian Conservation Biology Institute scientists confirmed a secondary rise in Mei Xiang's urinary progesterone began July 20. That rise indicated that she would give birth to a cub or experience the end of a pseudopregnancy in 30 to 50 days. The panda team began monitoring Mei Xiang 24 hours-a-day Aug. 20, after veterinarians detected what they believed was a developing fetus on an ultrasound Aug. 19.

What do you do during the health checks?

When the panda team conducts a health check they have a list of things to accomplish. They will measure the cub’s body weight, assess hydration, take a body measurement, check the oral cavity, check the umbilicus, check genitalia and rectal area, palpate the abdominal cavity, take a fecal culture, take the rectal temperature, listen for a heartbeat and lung sounds, and collect any urine produced.

How do you swap the cub from the den?

Mei Xiang’s den was rearranged earlier this year to allow the panda team to get closer to her and a cub to do health checks, or retrieve the cub. There is a barrier in the den, which keeps members of the panda team safe when they enter the den with Mei Xiang and the cub. Mei Xiang and the keepers are never on the same side of the barrier.

When the panda team removes the cub from the den for a health check a minimum of two keepers are always present. (No more than three keepers enter the den at the same time.) One keeper focuses on retrieving the cub, and another keeper monitors Mei Xiang. Keepers offered Mei Xiang bamboo, juice, sugarcane or honey water while they retrieved the cub during the first weeks of his life. Now that Mei Xiang is leaving the cub more frequently for longer periods of time, keepers can retrieve her from the den while Mei is eating in the adjacent enclosure.

They will pick the cub up with a gloved hand.

Why did a keeper come from China to help?

Li Guo the giant panda keeper visiting from China supported the National Zoo's panda team after Bao Bao was born in 2013, and returned this year. He is a giant panda cub nursery expert. Li has extensive experience caring for cubs.

Didn't Mei Xiang give birth to twins?

Yes, Mei Xiang gave birth to two cubs Aug. 22. The first was born at 5:35 p.m. and the second was born at 10:07 p.m. The panda team immediately implemented the Zoo's Giant Panda Twin Hand-Rearing Protocol after they observed Mei Xiang having difficulty caring for both cubs. Developed from the experience and success of Chinese partners and other zoos, the hand-rearing protocol provided the panda team with several strategies to manage twin cubs. Swapping the cubs between mother and hand-rearing is a proven method that enables zoo staff to best care for twins in the event that the mother cannot manage two cubs, which was the case with Mei Xiang. When swapping the cubs became difficult, the panda team had in their possession the smaller cub, which was losing weight, needed calories and energy, and was at risk if he remained away from Mei Xiang for a prolonged period of time. The cub’s best option for survival was to receive supplemental feedings via bottle and tube, but both techniques present risks. The team witnessed some regurgitation of food during one feeding, so the cub was started on antibiotics as a preventative measure.

The smaller cub was with Mei Xiang from about 2 p.m., Aug. 25, until the morning of Aug. 26. When the panda team swapped the cubs, they assessed the cub and had concerns because he had not increased in weight, appeared weaker and exhibited possible respiratory issues. He died shortly after 2 p.m. Based on the necropsy's gross findings, Zoo pathologists and veterinarians determined the most likely cause of death to be complications associated with aspiration of food material into the cub's respiratory system resulting in the development of pneumonia.

The cub was male, fraternal twin to the larger cub, and sired by Tian Tian.

Did Mei Xiang reject her smaller cub?

No. Mei Xiang cared for whichever cub was in the den with her. But female giant pandas struggle to care for more than one cub at once. That is why the panda team was swapping cubs, so Mei Xiang could take care of one at a time.

Is that a mouse in the den?

Several of you have mentioned seeing a mouse that occasionally runs through Mei Xiang's den. The Giant Panda building is a secure, dry area protected from the elements, so it is inherently attractive to all sorts of opportunistic rodents. The food that our giant pandas eat also attracts mice. We have a team of pest management specialists who work with keepers to reduce and control our visiting rodent population throughout the Zoo. And although we diligently work to exclude them, rodents are amazingly smart animals (something you can learn more about at the National Zoo's Think Tank exhibit). Our pest management team has even observed rodents outsmarting traps by flinging them against walls, and then making off with the bait. In addition, we refuse to use pesticides in our panda exhibit and so that makes the challenge of controlling our rodent population a little more difficult.
Of course, much as we admire rodents' cognitive abilities, we would still prefer them not to be in with our animals. Fortunately, Mei Xiang is a 200-pound bear with strong instincts to protect her cub. No mouse-however clever or cunning-poses a serious threat to her or her cub.

How can I get the latest updates on the panda cub?

Follow the Zoo and Conservation Biology Institute's #PandaStory on Instagram (@SmithsonianZoo) for all of the latest on the giant pandas. Major updates will also be shared on the Zoo’s Facebook page, and through Twitter (@NationalZoo), and through the Giant Panda Bulletin e-newsletter.

How can I help pandas?

Support the Zoo's giant panda conservation efforts at the Zoo and in China by giving to the Giant Panda Conservation Fund. Donate now.