panda conservation


Our Panda Conservation Program

Bai Yun has been a wonderful ambassador for pandas.

Bai Yun has been a wonderful ambassador for pandas.

When Bai Yun arrived at the San Diego Zoo back in November 1996, we all had great expectations for the San Diego Zoo’s panda conservation program. And we knew that these expectations rested squarely on Bai Yun’s beautiful black-and-white shoulders. In the years since, our panda conservation program has grown and has achieved a number of notable successes.

At the center of it all is Bai Yun. Of course, Gao Gao, too, has been extremely important to the success of our breeding program at the San Diego Zoo. Not all male pandas show appropriate breeding behavior, so Gao Gao’s arrival in San Diego in 2003 enabled us to fulfill our goal of studying giant panda reproduction, from breeding to maternal care. However, Bai Yun’s importance to our conservation program goes beyond her successes as a mother, as she has truly exemplified the role of conservation ambassador. Engaging and fascinating the public for the last 18 years, she is the quintessential giant panda, emblematic of the inherent beauty and value of wildlife.

Bai Yun will be 23 years old in September. For those of us who have watched her over the years, we are amazed at her consistent good health, youthful behavior, and appearance. However, this year, her estrous behavior has not been what it has been in the past. Can Bai Yun be heading toward reproductive senescence? Heading into her 23rd year, the answer, most likely, is yes; however, we won’t know for sure until next spring. As of this writing, Bai Yun has not shown more than a minimal level of the behavioral changes that are typically associated with estrus. Back in March, we saw a bit of scent marking and some water walking, behaviors that normally indicate that estrus is coming. However, the expression of these behaviors did not escalate, and soon after they began, they ceased. Since then, Bai Yun has been “quiet.” While estrus can occur into June, the vast majority of breeding, including for our bears here, occurs in March and April,

When Bai Yun gave birth to Xiao Liwu in 2012, it was widely noted that she was the second-oldest giant panda to give birth. While an impressive statistic, that notable milestone provided us with valuable information regarding the finite nature of a female’s biological capacity to produce offspring. Male giant pandas, like other male mammals, can theoretically sire offspring later in life, though for wild pandas, other factors may get in the way of this, including competition with other males for breeding access to females and choosy females that may not be interested.

Bai Yun has given birth to 6 cubs over the past 15 years. While some other females have given birth to 10 or more cubs, the number of litters a female has is typically no more than 6 or 7. For example, between 2004 and 2013, Bai Yun’s first daughter, Hua Mei, has had 10 cubs from 7 litters. While Hua Mei is 8 years younger than Bai Yun, it will be interesting to see whether or not she has more cubs in the coming years. These contrasting mother-daughter patterns are at the heart of one of our research questions: What are the limits of reproductive output in the species?

In some panda breeding facilities, cubs are weaned earlier in order to promote successive annual breeding opportunities. In other facilities, cubs are weaned at about 18 months, mimicking what we believe is the more natural timing of weaning. In these cases, females will only be able to breed every two years. Given this, we might expect to see females that breed every year producing 15 litters over their reproductive lives. However, this does not appear to be the case.

Understanding what governs female reproductive output in giant pandas has implications for both captive breeding and conservation of wild giant pandas, and we are currently analyzing a fairly large volume of data to address this question. Is reproductive output governed exclusively by chronological age? Or is it governed in part by health and vigor? And how does variation in inter-birth-interval (the time between successive pregnancies) influence a female’s lifetime reproductive output? We hope to have some answers to these questions in the coming months.

I have to admit that I never get tired of watching our giant pandas here at the San Diego Zoo. While the excitement of a new cub is undeniable, I know that I will enjoy watching Bai Yun and Gao Gao relax this summer, while young Xiao Liwu explores and plays, enjoying his first summer as a solo panda. Our panda family exemplifying their roles as ambassadors for conservation!

Panda Yun Zi in China.

Update on panda Gao Gao, May 11, 2014: Thank you for all the Gao Gao well wishes! He is doing well post surgery and is enjoying spending time in his back bedrooms. There he is catered to by his keepers 3 to 4 times a day, and he lets them know when he wants back scratches. Gao does have access daily to an off-view exhibit that has a panda camera in it, although he seems to prefer to enjoy the air-conditioned bedrooms, his black sleeping tub, and his keepers’ attention.


Pandas: How Far We’ve Come

Su Lin is at home in China.

Su Lin is at home in China.

Traveling to China is always an adventure, and the prospect of seeing old friends and long-time colleagues at the International Panda Symposium in Chengdu was exciting! The symposium was truly a great opportunity to listen to scientists from around the world share their updates on current research projects, overviews of the incredible successes for panda conservation achieved over the last 20 years, and important directions for our conservation research efforts for the years to come. We also had an opportunity to visit the Chengdu Research Base for Giant Panda Breeding, where we saw the many panda cubs and young adult bears that have been born there in recent years. There is still so much to learn regarding pandas and their conservation, but it is amazing how far we’ve come in the past 20 years!

On this trip I was also able to check in with staff from Wolong and Bi Feng Xia regarding the status of the San Diego Zoo-born pandas. Having watched their births, first days of life, and years of development into healthy sub-adults, I think we all love to hear how Hua Mei, Su Lin, Zhen Zhen, and Mei Sheng are doing.

Hua Mei, our first-born cub, continues to show that she has her mother’s “good-mom” genes. Now 14 years old, she produced another cub (a male) on July 18, 2013, at Wolong, making her the mother of 10! Both mother and her newest cub are doing well.

Eight-year-old Su Lin had a normal estrus this past spring at Bi Feng Xia and mated naturally several times but did not produce any cubs this year. Regardless, she is doing well and living at Bi Feng Xia. Ten-year-old Mei Sheng mated naturally this year at Bi Feng Xia, too, but we don’t know yet whether he has sired any cubs, as DNA tests are not performed right away to determine fatherhood.

Little Zhen Zhen, now six years old, is currently weighing in at a robust 220 pounds (100 kilograms)! She mated in 2013 and produced a cub that, sadly, did not survive. Zhen Zhen is also living at Bi Feng Xia and doing well.

Megan Owen is an associate director for the San Diego Zoo Institute for Conservation Research. Read her previous post, News about Zhen Zhen.


Live-Tweeting Exam 17

This morning was by far one of the coolest moments of my career here at San Diego Zoo Global. No wait, one of the coolest moments OF MY LIFE. After months of fawning over adorable photo after adorable video, I was finally able to meet our little celebrity panda cub in person! And let me tell you, Xiao Liwu lives up to all the hype. I didn’t think it was possible, but he’s even cuter in real life.

So why was I there? To tweet, of course! As the social media guy, that’s what I do best, and boy did I tweet. This morning was our first ever up-close live tweeting of a panda cub exam, and I’m proud to have been part of it. In case you missed my tweets, I’ll give you a play by play.

When I first arrived at the exam room, our brilliant photographer Ken Bohn and equally brilliant videographer Maria Bernal-Silva were all suited up and ready for the cub to arrive. I was hanging in one corner of the room along with panda staff, and there was a bit of an anxious vibe as we waited for the exam to begin.

When keepers brought Xiao Liwu in, a hush fell over the room, which was soon replaced by giggles and squeals as Liwu squirmed all around. He was a little wet and muddy from the rain, as was expected, but he was bigger and more vigorous than ever.

Some bamboo leaves and a little tree log were placed on the exam room floor for Liwu to play with, but he showed little interest. He kept trying to crawl to other areas of the exam room, but he did stop for a second to mouth some bamboo that was offered to him.

Believe it or not, in between all the swooning some real science actually occurs. The Panda Team performs all kinds of physical diagnostics to ensure our little man is thriving. During some measurements, Xiao decided to entertain us with a panda “headstand.”

The exam was over before I knew it. It ended so fast, and it was such an unreal experience, that it’s almost like it didn’t even happen—like I dreamed it. But it happened, and I’m incredibly honored to have experienced it.

It was not only a pleasure to be around Mr. Adorable himself but to experience the inner workings of our panda conservation program firsthand and to be a brief part of the incredible conservation work that our team does. I am forever in awe of our Panda Team’s passion and dedication to saving this endangered species.

Matt Steele is the social media planner for San Diego Zoo Global.

Note: Xiao Liwu weighed 14 pounds (6.4 kilograms) this morning and measured 27.5 inches (70 centimeters) long.

Click on image to enlarge.


Su Lin: No Worries!

Don't worry about Su Lin, be happy for her!

Recent news from China regarding Su Lin has sparked a number of questions, and some concern, from our blog readers. Reports in the news have stated that Su Lin is “pregnant” and that she has been moved to a “semi-natural” enclosure, implying that her offspring may be a candidate for reintroduction. I’d like to address these concerns.

Su Lin is now living in the large, semi-natural enclosure. Rest assured, the important word in that description is “semi”! Su Lin will be monitored in order to ensure she is thriving in her new environment, albeit in a less hands-on way, and she will have an abundance of food resources from which to choose. While her new enclosure is large and naturalistic, there will be no other bears in there with her, or any other “threats” to her survival. Bamboo will be plentiful, and we are very, very confident that she will thrive, both physically and psychologically, in her expansive new digs.

Regarding reports of Su Lin being pregnant: We know that Su Lin bred naturally this year, but we still don’t know for sure if she is pregnant. That said, the track record for successful pregnancy after natural mating is very good, and so there is a high likelihood that Su Lin is pregnant. To date, the only surefire way to determine if a panda is pregnant is through ultrasound. And in cases where ultrasound has been used to confirm the presence of a fetus, it is typically about 20 days before the birth at the earliest. Most pandas give birth between July and September, and we have no reason to suspect that Su Lin would be any different. So, until we hear that Su Lin has “given birth,” anytime you read that Su Lin is “pregnant,” interpret this news as “probably pregnant.” ☺

The potentially pregnant Su Lin has been chosen to participate in this important conservation program because of her health, both physical and behavioral, and her heredity. We will continue to update everyone regarding her life and milestones, and we here at the Giant Panda Research Station will continue to be proud that a San Diego Zoo-born panda was chosen to be a part of this program. To live in such a large enclosure, with a consistent food source and the sensory diversity and excitement of a natural bamboo forest, sounds like “panda heaven.”

Megan Owen is a conservation program specialist at the San Diego Zoo Institute for Conservation Research. Read her previous post, Panda Conservation: Our Priority.