Smithsonian National Zoological Park l Friends of the National Zoo



Fall Updates

November 26

On these recent cold mornings, the pandas have been very active. They are eager to go outdoors to eat, and then it is time to wander and play. Tian Tian recently spent a morning scent marking after we shifted him into a new enclosure. Mei Xiang then had to scent mark all over ALL of his marks as she passed through the yard. These behaviors will gradually increase over the winter and into spring. On some mornings, the adults do not choose to play and we are left to wonder what is different about those days.

When Tai Shan is rotated, he also explores the other pandas’ scent marks but he does not mark over them yet. He is also very interested in watching the adults at first but then, like the adults, resumes his own solitary routine. His favorite sleeping place in yard one is under the perfectly shaped Douglas fir toward the back of the yard. What a beautiful present he makes! With Tai’s improved attitude and appetite, we are weaning him off all of his medications. Although his bamboo consumption is still low, he is consuming ornamental grasses and all of his biscuits and produce. Tai’s favorite treats are still his fruit, in any presentation, and honey... dripped on any and all enrichment items, if you please.

November 13

Tai Shan is a healthy three-year-old male panda cub that appears to be experiencing what panda researchers and veterinarians have loosely termed the “summer slump.” This is a period, generally during the summer, when pandas decrease their regular bamboo consumption. Weight loss and lethargy may accompany this period. This is not uncommon in giant pandas. To ensure that Tai Shan had no medical cause of his decreased appetite, we recently (on September 23) anesthetized Tai Shan for a full work up. We noticed a moderate inflammation of the gastrointestinal tract, and placed Tai Shan on medications. Since then, his attitude and appetite have improved. However, it is not clear whether this is due to the medications or coincides with the end of a seasonal decrease in appetite. A period of improved appetite typically follows the “summer slump.”

We are very fortunate at the National Zoo to have many areas of expertise, and decades of collective experience in giant panda management, spanning fields from behavior and reproduction to health and disease. We also have a close relationship with our Chinese colleagues. Our veterinary and curatorial staffs routinely consult with all members of “our” collaborative panda team—both nationally and internationally—and we are confident that Tai Shan will soon emerge completely from his summer slump and resume his usual appetite.
— Suzan Murray, Chief Veterinarian and Head of the Department of Animal Health at the National Zoo.

November 11

Tai ShanTai Shan has been consuming more bamboo and biscuits since the last update. Similar to last year at this time, he is consuming between 13 and 15 pounds of bamboo daily. During the winter and spring, this amount will increase to 33 to 44 pounds daily. Tai Shan currently weighs 160 pounds. Recently he has been spending a lot of time wandering in his enclosures.

Our large enclosures allow the pandas to wander and establish trails similar to what has been observed in the wild. When the pandas are rotated through all of the enclosures, they have an opportunity to investigate each other's scent marks. Rotation through the yards also allows them to interact at the mesh, mimicking chance encounters along the trails and stands of bamboo in the wild. These interactions are brief, as none of the pandas seems very interested in each other. Tai Shan and Tian Tian had a five-minute interaction at the mesh recently, and Tian sniffed him intently for a few minutes before wandering off. Mei Xiang showed no interest in Tai. After watching the adults for a few more minutes, Tai wandered off to patrol the yard just like Tian.

This is the time of year when testosterone levels begin to rise in male pandas in preparation for breeding season. Tian was observed pacing and scent marking recently, which is an early signal for what lies ahead! After the summer fast, Tian currently weighs in at a svelte 255 pounds. You can almost see his muscles ripple as he powers around the yard.

We collect daily fecal and urine samples from Tai for a study to learn about the onset of puberty and the associated hormonal rise in young male pandas. This has not been documented in pandas as young as Tai Shan. As Tai matures, he is losing interest in playing with toys and is beginning to act more like an adult. If we apply honey to his toys he will interact with them only for the treat. On one recent morning we found Tai’s cage completely wet. Water and snow never lose their power to elicit play! On these cool mornings we've been having lately, all the pandas are beginning to climb and play in the trees again.

Mei Xiang currently weighs in at a total of 241 pounds of beautiful. On these cool early mornings, Tian Tian always solicits play from her. These play sessions are fun to watch and make for fit pandas. Mei does decline Tian’s wishes on some days, foregoing the play session with a moan and a swat, for a much preferred longer nap time.

Six months ago, a magnitude-8.0 earthquake devastated central China’s Sichuan Province—home to 46 giant panda reserves and 75 percent of the estimated 1,600 wild pandas. The Zoo’s giant panda conservation programs in that region continue. Efforts are also underway to rebuild a destroyed breeding facility and assess the impact on panda habitat. Our research efforts recently received a boost through a $50,000 donation by Lee Kum Kee, a leading maker of authentic Chinese sauces.

October 28

The pandas are just beginning to strip the stalks of the bamboo during meal times. This is an indication that we are at the beginning of the seasonal increase in bamboo consumption. Also, during this time of the year the pandas graze on the grasses in their Tian Tian and Mei Xiangenclosures. Grasses, including bamboo, store carbohydrates in their stems or stalks when the weather turns cold. All three pandas are exhibiting these behaviors now.

Pandas are bears whose digestive systems have to process high-fiber bamboo. It is amazing that a bear would ever evolve to eat a diet that it is so ill equipped to consume. The panda's digestive system produces a lot of mucous, which may help to protect their intestinal lining. Interestingly, when our pandas consume less bamboo we frequently see more mucous stool production. On the days when they are going to produce mucous they become very lethargic and go off of their food. This period may sometimes last three or four days. Individual pandas respond differently and there is tremendous variation in the consistency and color of mucous stools. Some may be thick and look like vanilla or caramel pudding (sorry, pudding fans!) while others may be watery or foamy like your favorite soft drink.

We have been monitoring Tai Shan’s food consumption more closely because of his recent diagnosis of an inflammation in his esophagus. It is difficult to determine whether Tai has recently increased his food consumption due to his medications or the time of year, probably a bit of both. During this period of seasonal appetite loss, most adult pandas seem to maintain or lose a small amount of weight. However, there is always individual variation. Tai Shan has lost weight since July, giving him a longer and lankier appearance. Unfortunately, there is not a large data set on seasonal bamboo consumption and growth rate for young pandas. All Tai Shan’s medical evaluations indicate that he is healthy. In addition to his recent physical under anesthesia, positive reinforcement training allows us to examine him and collect blood for evaluation on a regular basis. As he gradually increases his food consumption we expect him to regain weight rapidly.

Here's a graph of the seasonal change in bamboo consumption for Mei Xiang and Tian Tian from 2001, when Mei was about Tai's age.

food intake chart

October 1

Last week was an eventful one for Tai Shan. Tai was given a complete physical under anesthesia. Recently, he had been reluctant to eat leaf-eater biscuits. This is the time of year when pandas can be picky about their bamboo, but they usually continue to consume their biscuits. They never lose interest in the sweet and juicy produce (apples, pear, carrot, and sweet potato)! We decided to give Tai a physical so we could get a thorough body assessment. This exam also gave us an opportunity to evaluate a panda during its seasonal period of low energy and appetite loss.

Tai is in excellent health. His body condition, from his nose to his tail, with special attention to his teeth, checked out just fine. Of course, we already knew that he is just perfect! One interesting finding was some inflammation of his esophagus, similar to the condition called acid-reflux in humans. This was discovered by using an endoscope to look at his digestive tract. Similar medications are used with zoo animals to soothe the irritated esophagus. Although a lot is known about this condition, especially in people and some domestic animals, we are providing new information to our medical database on pandas. And I'm happy to report that Tai Shan is chomping on his biscuits like a champ again!

Zoo animals get physical exams as part of a comprehensive preventative health-care program. Scheduling is dependent on many factors related to the need to monitor health, based on knowledge of the natural history and health of particular species, experiences in zoos, and individual medical history. Every time a procedure is done, we build upon a comprehensive and ever-growing body of information on exotic species.

September 19

Mei, below, and Tian, aboveMei Xiang and Tian Tian have been spending a few hours each morning together for the past three weeks. It is as though nothing has changed when they are reunited after their long separations. Silent play is followed by long naps in their respective enclosures. What a treat it is to watch them so active and engaged!

They usually start out eating bamboo side by side. Mei Xiang always reaches over to take Tian’s choice piece of bamboo, forcing him to find another piece. After eating, the play begins!

It is not unusual for them to use the trees, as well as the deadfall in these tumble and wrestling sessions. Both Mei and Tian solicit play by bouncing up into the air, their heads tossing and paws waving, until they make a solid landing on the other’s body. They usually tire after one or two sessions and then they go their separate ways. Lately, Mei Xiang is back to napping on the side of the grotto in yard two, while Tian Tian rests inside the grotto in yard one. Some of the rotten deadfall has met its demise under their recent antics and will need to be replaced. Meanwhile, the rotten wood is great for scent anointing, a sort of panda perfume.

Tai ShanWhile the adult pandas’ activity and appetites have improved, Tai Shan is still rather inactive, consuming only small amounts of bamboo. During the summer months, the pandas become lethargic and reduce their bamboo intake. Gradually, they pick up their appetite during October and November. This is also the time of the year when we see the pandas graze on the grasses in their enclosures. Tai was observed eating a paw-ful in very slow motion, before losing interest in it.

He was moved to yard one this week so that he could investigate the adults' scent and observe their activities. Tai quietly investigated their scent marks, occasionally vocalizing with just the softest chirp, before taking a long nap.

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