Bai Yun


Good Weather, Good Food

Gao Gao has been in fine form lately, climbing trees and scent marking.

Gao Gao has been in fine form lately, climbing trees and generally giving keepers quite a show!

Lately, as I have been narrating down at the panda enclosure, I’m seeing the bears relax, sit back, and enjoy the food. As many of you know, we feed several different types of bamboo to our bears, and in recent days they have really been enjoying themselves! Bai Yun will often eat for a few hours at a time, and even Mr Xiao Liwu has been doing very well ripping the bamboo apart. And it seems while they’ve been relaxing, panda fans have been thinking; we have been getting a lot of questions about breeding the bears this year.

As of last week we have not seen any change in Bai Yun hormone reading or physical state. However, on a fairly regular basis we have observed her scent marking repeatedly around the enclosure, and even engaging in “water play”, a behavior we typically see when there is a hormone shift. As it is still early for her regular breeding season, we expect to continue watching her closely over the next couple of months and will monitor any progression towards an estrus. She is extremely healthy; one of the benefits about being captive born is a fantastic health package!

Gao Gao has been eating extremely well in his off-exhibit digs, and has been climbing up and down the trees giving our keepers quite a show in the back area. Engaging in handstand scent markings is always fun to see, and having him this active is a nice change of pace.

Now, please remember: even though he is quite vigorous right now and showing a lot of enthusiasm, we cannot put him in with Bai Yun unless we have positive evidence showing her in estrus. Our vet staff will ultimately have the final word on breeding the bears, and rest assured they always keep the animals’ best interests in mind and at heart.

Little Mr. Wu has also been showing lots of energy and spunk. On a daily basis we see him run around the enclosure, playing with enrichment that keepers have put out for him. Our guests have enjoyed watching him and his moves, and it has been great to show our guests what these bears are capable of. Over the next few months we may see more activity and more growth spurts!

Come see us soon!


Pandas in Winter

Cold temperatures? Extra bamboo? Works for Bai Yun!

Cold temperatures? Extra bamboo? Works for Bai Yun!

For the first time in a long time, our pandas are actually getting some truly winter weather. We’ve had some rain recently, and temperatures in the first week of the new year were really low for our region. And the geography of the Zoo means some parts of the grounds feel the chill more than others; Panda Canyon is usually 10 to 15 degrees cooler than the main entrance (where temperatures were in the mid-50s). Although the staff is feeling a bit chilly, the bears are loving this weather!

Giant pandas have a very thick, dense fur coat and like most bears they will try to gain as much weight as possible for winter, but they do not go into torpor (commonly called hibernation). Unlike their counterparts in China and zoos in colder parts of the world, our pandas don’t usually have much of a winter to deal with, but rest assured they are all doing just fine with this cold snap!

We always offer more food than what the bears will actually eat. This allows them to have variety in their diet but also giving them access to extra calories should they so desire. Our pandas do not weigh as much as other pandas that go through more severe winters, because they don’t need the extra insulating fat layer here in San Diego.

As someone who has worked both directly and indirectly (as a Panda Narrator) with the bears, I can honestly say that I love watching them in cold weather. You get to see them eat more and the younger pandas get a little more hop to their step. Yun Zi was one of my favorites to watch in winter. He was always an active fellow, but when it was cold or raining he’d roll in the mud and really tear his exhibit apart. Not always fun to clean up after, but a blast to observe!

No matter what the weather, Bai Yun tends to do her normal thing—eat till she’s tired, then take a nap. I often joke that she’s been here in San Diego for so long nothing much can surprise her anymore. Gao Gao will remain off exhibit in the North Exhibit, with regular access to his bedroom. The perk about having the back area to himself is that he can pretty much run his day however he wants. Inside or out he’s got full reign of the area in the back. Mr. Wu will be on exhibit, and I’m looking forward to watching him and see how he reacts to this cold snap. I know it’s not cold compared to where a lot of you are from, but for these bears, and us, it’s definitely a change!

Happy New Year and hope you are all well! Come see us soon in 2015!

Anastasia Horning is a panda narrator and keeper at the San Diego Zoo. Read her previous post, Dealing with Noise in Panda Canyon.


Dealing with Noise in Panda Canyon

Bai Yun is a pro at dealing with activity around Panda Trek.

New noises catch Bai Yun’s attention, then it’s back to “business as usual.”

As many of you have seen on Panda Cam and in person, young Mr. Wu is off exhibit at times and only Bai Yun is present. Rest assured there is nothing wrong with him and he is perfectly fine. Our Zoo is coming up on its 100th birthday soon, so we are improving areas and updating where we can. With that comes a certain amount of noise that we really cannot get away from, so we closely monitor our animals for any signs of stress.

Xiao Liwu, being younger and not as experienced with new sounds, is more likely to react to the construction noise. Bai Yun is typically a pro at changes and has been managing extremely well. One of the benefits of having a panda narrator keeping an eye on the bears is that the narrator is familiar with each animal and can tell the Panda Team when there is a change in behavior. Our Web Team will always do its best to notify you when there may be a change in who is out for viewing, but the fact of the matter is that things can change quickly here, and we often need to make judgment calls quickly, too.

When the bears are off exhibit, they still have an outside yard they can go into if they so choose. Both of the north exhibits are close to bedrooms and, if needed, the keepers can give the pandas access to the bedrooms. The bedrooms offer a dry and cozy area for the pandas. Keepers often fill a giant tub full of hay or shavings for the bears to rest in, and there is a garden room for them to go into as well. Having a building between them and the extra noise often makes a huge difference in a panda’s comfort level and helps diminish any stress behavior.

Bai Yun is an expert at dealing with noise. When we were building the rest of Panda Trek, she was still able to be out in the main viewing area, right next to the noise. There were, of course, days where we noticed that she was a little annoyed with the activity level and so gave her access to her bedroom. There are several cameras in the area, and the panda narrator and guest ambassador all keep an eye—and ear—out for her to make sure that she is comfortable. In many situations, just giving her 10 to 15 minutes in her bedroom to get a little break will often set her right. In addition, we always do our best to make sure that she has extra bamboo that she is fond of and to try and keep her busy with enrichment.

Come see us soon, and please know that we are always thinking of how to make this an easy time for our animals!
Anastasia Horning is a panda narrator and keeper at the San Diego Zoo. Read her previous post, Talkin’ about Takins.



First Snow Day for Panda Cub!

Yun Zi was 2 when he saw his first snow.Tuesday, March 19, starting at 7 a.m., we are preparing for snow in the panda exhibits. We are very excited and thankful to all the panda fans who donated money to give this wonderful enrichment to our giant pandas. I am sure we will see you at 9 a.m. sharp in person or starting around 8 a.m. on the Panda Cam!

It’s a bit of a process to actually make snow and put it in the exhibits. We have a truck that comes in and is specially designed to turn large ice blocks into snow. There are large hoses that we can hold and deliver (spray) snow into the entire panda exhibit. Snow will be blown into Bai Yun and Xiao Liwu’s north exhibit and into Gao Gao’s exhibit in the main viewing area.

Sadly, Yun Zi’s new tree will not be done in time (due to a couple of days of rain), and he will stay housed next to Bai Yun and Mr. Wu for a few more days. But don’t fret! Yun Zi will be getting snow, too, and we will make sure he has a mound of it to play in.

We are all excited to see how brave Mr. Wu is and what his first reaction will be when he puts his paws in it. Hopefully, it will be a wonderful play day for both bears and guests!

Jennifer Becerra is a senior keeper at the San Diego Zoo.

Here’s Zhen Zhen when she saw her first snow:


My Moment With Our Black and White Celebrity!

It finally happened, I was able to help with a cub exam! I have been waiting for this moment since my first look at the cub during my night watch shift. As we began setting up for the exam, my excitement quickly turned to nervousness, and my mind raced. There were cameras, researchers, veterinarians, nutritionists, fellow keepers and supervisors, and it was up to me to keep our celebrity calm!  

Then it was time: Bai Yun shifted out to her breakfast, and she was calm. Now was my chance to pick up the cub, weigh him, and bring him out for his exam. I picked him up and placed him on his blanket, along with several bamboo leaves that I had to clean off of him so he would be camera ready. I gently placed him on the scale; he weighed 7.26 pounds (3.29 kilograms)! Now out to the cameras, the veterinarian, and the nutritionist for his exam. He did so well! He made a few vocalizations here and there, and he is getting much more mobile–he even crawled–but the veterinarian and nutritionist were able to conduct a thorough exam. Success!

Jennifer Chapman is a keeper at the San Diego Zoo. Read her previous post, Night Watch: Mission Accepted.


Sensitive Subjects are My Job

Hua Mei was the happy result of artificial insemination.

Have you ever been to a San Diego Zoo Safari Park and had the Africa Tram driver warn parents of little ones that it is that time of year when the animals are breeding and their kids might have some questions about what they saw after the ride? This usually gets adults chuckling, and maybe even leads to a few “birds-and-the-bees conversations.” Well, imagine your job is to help in the reproduction of endangered species and that every person you meet eventually asks, “So, what you do for a living?” As a laboratory researcher in the Reproductive Physiology Division of the San Diego Zoo Institute for Conservation Research, I’ve learned to say, “Think of us as a fertility clinic for animals.” Here are a few examples I use to explain this idea:

Artificial insemination
One of our lab’s greatest achievements was the birth of Hua Mei, the first panda cub to be born at the San Diego Zoo. While her birth was due to a large-scale collaboration of many people from all over the Zoo, including scientists, curators, veterinarians, and keepers, our greatest contribution was the insemination. It became clear that male panda Shi Shi was not going to naturally breed female Bai Yun and that human intervention would be necessary. Barbara Durrant, the director of our division, was able to collect semen from Shi Shi and use it to artificially inseminate Bai Yun, resulting in the birth of Hua Mei.

Sun bear Danum arrived with the help of estrous cycle monitoring.

Estrous cycle monitoring
Often when women are trying to conceive, doctors monitor their cycle using techniques to predict when ovulation will occur. Many of these techniques are not feasible to apply to our collection animals because they would require sedation. Instead, in addition to urine and fecal hormone monitoring, we collect vaginal cells and monitor changes using a modified Papanicolau stain and some good, old-fashioned microscopy work. The cells in many mammalian species have been found to change in color and shape as estrus progresses. Unlike the Pap smear women are familiar with, which checks for cervical cancer, we monitor the changes in vaginal cells, which requires a far less invasive method of collection. These cells can be obtained with operant conditioning or positive reinforcement training of the animal. It’s amazing what a sun bear will do for some honey water!

An example of a success achieved using this method is the birth of our first Bornean sun bear cub: Danum. A shift in vaginal cells from one dominant color to another, combined with behavioral observations by keepers and scientists, allowed us to pinpoint the right time to introduce the normally solitary male and female to each other with a decreased risk of aggression and increased chance of breeding.

In-vitro maturation (IVM), in-vitro fertilization (IVF), embryo development (ED)
Many of us remember the term “test tube babies.” Today, IVM, IVF, and ED techniques are being employed all around the world, enabling couples to have children despite a variety of fertility issues. Often a human female is given hormones to produce many oocytes (eggs) that are retrieved from her ovaries using ultrasound-guided aspiration. These oocytes are put into a medium specifically designed to help the oocyte mature (IVM) in preparation for fertilization. Sperm is then introduced to the egg in a petri dish (IVF) or by a procedure called intra-cytoplasmic sperm injection (ICSI).

The oocyte is then put back into the medium designed to promote embryonic growth in an incubator. That embryo is then implanted inside the female or frozen for future use. In our lab we are using these same techniques to try to produce embryos from endangered species. Our challenge is that we work with a variety of different species, all with their own special needs, and many of the oocytes we work with are from ovaries of animals that have passed away, leaving us one step behind in the maturation process. We have used these procedures on animals as common as cats and rabbits to animals as endangered as rhinos and polar bears.

It is no secret that the best part of this job for me is getting to see the fruits of my labor. I may be taking a petri dish that once contained oocytes and sperm out of the incubator and seeing a growing embryo, or standing in front of an exhibit watching an adorable sun bear cub climb up a tree stump, but the feeling of helping to create life is indescribable. My friends like to tell people I make babies. Well, if by babies they mean cubs, kittens, and pups, then I am happy to agree. It may not be the easiest job to explain to people, but I almost always get a response like, “That is so cool.” It is, and I finally found a way to tell people just how cool it is.

Nicole Ravida is a research coordinator for the Reproductive Physiology Division of the San Diego Zoo Institute for Conservation Research. Read her previous post, Creating a Sperm Atlas.


Happy 21st Birthday, Bai Yun

Our birthday girl relaxes on her special day.

Happy 21st birthday to our panda mom, Bai Yun! It is hard to believe that 16 years ago, this beautiful, grand lady arrived at the San Diego Zoo as a curious, playful youngster, only to grow up and become one of the most popular pandas in the U.S.!

Bai is truly an ambassador for giant pandas. Since her arrival in 1996, we have learned so much from her about giant panda biology. As a result of this, she has raised worldwide public awareness on the plight of giant pandas in her home country of China.

Miss Bai has always been on the “cutting edge” of things. She has presented us with six beautiful cubs, making the San Diego Zoo the first in the U.S. and outside of China to produce the largest number of giant panda births! In addition, Bai almost broke the world record as being one of the oldest females to give birth in a managed-care facility. So many wonderful memories over the years, and yes, you guessed it, Bai is my number one panda!

For a birthday gift, Bai will be offered access to her garden room, after spending many months in her bedroom and den area. Here she can have more quiet and “personal” time away, but not too far, from her son. She can enjoy resting on her favorite platform, if she desires. We thought this was a fitting present to give our busy mom!

Happy birthday, Bai Yun, from your keepers and admirers. You are still as beautiful as ever, and we look forward to the future as we watch your new son grow!

Kathy Hawk is a senior keeper at the San Diego Zoo. Read her previous post, Panda Wins Best Mom Title.


Panda Cub: 704 Grams

Breathtakingly adorable! Click on image for a larger view.

All is well!

This morning, at about 7:15, we had our first opportunity to examine Bai Yun’s newest cub. For the past week or so, Bai Yun has developed a regular habit of leaving the den to get breakfast in her sun room. Today, we took advantage of Bai Yun’s breakfast outing to get our first real look at the cub. The exam lasted only 3 minutes, but in that time our veterinarians were able to determine that the 25-day-old cub is healthy and weighs in at a robust 704 grams (24.8 ounces or 1.55 pounds). For comparison, Yun Zi weighed 1,259 grams (2.8 pounds) at 29 days (see Baby’s First Exam), Zhen Zhen weighed 1,020 grams or 2.2 pounds at 26 days, and Su Lin was 618 grams (22 ounces) at 22 days. The cub was quiet at the outset of the exam, but soon enough gave us a great display of its strong lungs!

Veterinarians were able to do a quick, yet thorough, exam of the cub’s limbs, mouth, ears, and more, and we’re happy to report that everything looks good! While it may be a few more weeks before we know what the cub’s sex is, or whether or not it has webbed toes or a spot on its tail, today was an important step in confirming that this cub has the most important quality that a panda cub can have: good health!

Bai Yun also showed us her best maternal behavior. She began eating her breakfast away from the cub, in the sun room, as usual, when the cub emitted a loud squawk during the exam. Bai Yun made it clear that she wanted to return to the den to be with the cub, so the exam was halted. Her maternal behavior continues to be exemplary and, clearly, she is doing a great job taking care of her latest cub. We are all so lucky to see this amazing mother in action!

Megan Owen is a conservation program manager for the San Diego Zoo Institute for Conservation Research. Read her previous post, Panda Cub: True Colors.

Note: See more exam photos on our Panda Photo Gallery.


Pandas: You Asked, We Answer

The panda cub on August 15.

As Bai Yun and her cub continue to do well, staff at the San Diego Zoo’s Giant Panda Research Station have slowly begun to emerge from the constant efforts of watching over the den activities to return to tasks put aside during the crucial early postpartum period. I’ve been reading through some of your comments and questions and thought I could offer some feedback.

Regarding the repeated questions regarding Bai Yun’s age, her health, and her behavior with this cub: Bai Yun is doing just fine! She has been resting a lot, which is entirely normal at this stage postpartum. If this is your first panda cub, I encourage you to read through our blog archives and see that sluggishness on the part of momma bear is de rigueur at this stage. Pandas are bears, after all, and many bears experience months of fasting and rest coupled with the birth and early postpartum rearing of their young (see Pandas, Bears, and Pregnancy).

There have been some really good scientific papers written on the magnificent ability of female bears to lactate and care for their young without eating for long periods, noting that very little muscle wastage is evident despite these energetically costly events. Please don’t worry about Bai Yun. She is built for this, and she is taking good care of herself as well as of her cub. We are very pleased with their progress so far.

As an aside: you can see the activities in the den well, but you can’t see what Bai Yun is doing when she leaves the den. She has been getting regular drinks since day 1 postpartum. She has even been observed feeding on occasion. Although she isn’t consuming much yet, she has spent a little time feeding on bamboo and even snacked on biscuits. Her appetite will come back much faster than those cold-weather hibernators, but it is a gradual process. She is making expected changes to her intake every few days.

A few of you noted that the camera has been showing fewer close ups lately. We’ve started to add our other responsibilities into our day, and so when we do leave the monitoring room, we zoom out so the whole den is visible. I’ve noted that some of you are quick to record snippets of video when there is a nice, tight zoom on the cub. Keep sharing your videos with each other so that everyone can benefit from those close ups!

As to the heat in the area: yes, it’s been blazingly hot and humid in San Diego in the last week. But, as our moderator indicated, there is air conditioning in the bedroom area that opens to the den. This air is set to a constant temperature and can filter into the den. Even so, it can get hot in those mountains of China in the summertime; I recall a very sweaty walk up to George Schaller’s former research base in Wolong one summer afternoon. It was baking. The upshot is that these bears can handle a little heat, and Bai Yun has been very comfortable.

We still haven’t had the opportunity to take the new cub out of the den for its first exam. Bai Yun has been leaving the den, though not yet for the long periods we need to see before cub exams begin. That could change at any moment, based upon her needs, so stay tuned! Until that first cub exam, we won’t have a way to determine the gender of this youngster.

Suzanne Hall is a senior research technician for the San Diego Zoo Institute for Conservation Research. Read her previous post, Panda Cub: Furry and Fine.


Panda Cub: Late-night Observations

Bai Yun gets some rest with her cub secure in her arms.

Zookeepers are always “on call.” If we leave town, we let our supervisors know when we’ll be back, just in case they need us for anything. If an animal is sick, we work overtime. If there’s late-night construction, we’re at the Zoo at all hours making sure our animals are safe and secure. This is also true if one of our animals is expected to give birth or if she has a newborn.

Right now, the San Diego Zoo’s Panda Team has a schedule to insure that Bai Yun and her newest cub are observed 24 hours a day, 7 days a week. We began this schedule about a week before her cub was born and will continue to observe her 24 hours a day until the cub is at least 2 weeks old. Everybody involved with pandas takes turns rotating through the shifts. As I write this, it’s my turn to do the overnight shift.

So, here I sit, 11 p.m., in the video room of the Giant panda Research Station, watching Bai Yun and trying not to fall asleep. I have to say that I can’t complain much. It’s amazing to watch Bai Yun demonstrate her natural maternal instincts. Right now, the cub weighs only about 4 ounces (113 grams), so it’s my job to make sure that Bai Yun doesn’t sit, roll, or step on her itty-bitty cub. Bai Yun currently weighs around 220 pounds (100 kilograms) and has never accidentally rolled onto a cub. She’s very gentle with each of her movements and is constantly aware of where the cub is.

Of course, the cub is very noisy at this stage of its life and tells Bai Yun exactly where it is. If the cub wasn’t noisy, it would be easy for Bai to lose track of it. While on cub watch, it’s also my job to keep track of the cub’s vocalizations. I have to make sure that the cub makes some noise at least once every two hours. Believe me, that cub does a great job of keeping both me and Bai Yun awake all night!

The San Diego Zoo takes a hands-off approach when it comes to panda cubs; unless the cub or Bai Yun is in some distress, we do not interfere with her rearing of the cub. Bai Yun will barely leave the den for the first few weeks of the cub’s life. She keeps the cub cradled in the crook of her arm (much like humans cradle a baby in their arm) while she’s lying down or sitting up. If she does leave the den, the cub will not accompany her until it is able to follow her on its own. So far, Bai has left the den only twice (for 30 seconds to 1 minute each time) to get a drink of water. During these very brief moments, we have been able to see the cub!

It may surprise you to hear that these are the only glimpses of the cub that we’ve had. If you’ve been keeping a constant eye on Panda Cam, you’ve seen the cub the same amount of time as we have. We’ve been able to isolate these brief time periods on our fancy new DVR and have been able to get a concrete idea of how the cub is doing. It has a beautifully chubby belly, is very mobile, and definitely has a good set of lungs. That cub squawks the entire time Bai Yun is out of the den, letting her know that it is not happy to be left alone. Of course, in response to its vocalizations, Bai Yun immediately returns to keep the cub warm and safe.

During the next couple of weeks, we’ll see the cub begin to look like a giant panda. Its coloring will begin to come in first, before the cub even opens its eyes. After its skin pigmentation develops, that fuzzy, adorable cub fur will appear. Then the cub will begin to open its eyes. This will all develop in the next two to three weeks. During that time, Bai Yun’s trips out of the den will become more frequent and will be a bit longer. When Bai is comfortable leaving the den for roughly 10 minutes or so at a time, the Panda Team will begin talking about examining the cub. Until then, we’ll continue to watch the monitors and wait, just like you…except, I hope, you’re getting some sleep in the middle of the night!

Juli Thatcher is a senior keeper at the San Diego Zoo. Read her previous post, Gao Gao Getting Big Big.