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About Author: Suzanne Hall

Posts by Suzanne Hall

29

World Orangutan Day

Today is World Orangutan Day! On this day, organizations around the globe are highlighting the plight of one of our closest living relatives, the tree-dwelling “person of the forest.” These special creatures are not important just because they are large mammals, or because they remind us of ourselves, but also because they are so integrally connected to the forests they inhabit. With more than 500 known plant species encompassed by their diet, this red ape is a significant factor in seed dispersal in the ancient forests of Indonesia and Borneo.

But the forests, and the orangutans that depend on them, are dwindling. Habitat loss is occurring in Southeast Asia at an alarmingly rapid rate, with Indonesia and Malaysia losing more than 6.5 million hectares (more than 25,000 square miles) in the last few decades. As a result of this habitat loss, the two orangutan subspecies are experiencing a steep decline. The Sumatran Orangutan is critically endangered; the IUCN estimates that no more than 7,300 remain in fragmented patches of forest, primarily in Aceh, Indonesia.

Forest loss in orangutan habitat has a number of causal factors: mining operations and tree harvesting for the pulp and paper industry are two of the usual suspects. But one of the most significant reasons for deforestation over the last twenty years was the rampant growth of the palm oil industry. Production of oil palm, an agricultural commodity that grows only in tropical regions, has skyrocketed: between 1990-2010, Indonesia experienced a 600% increase in land dedicated to the crop. To protect and preserve orangutans, and other species dependent on these forests, conservation biologists have been searching for a way to stem the tide of deforestation due to palm oil expansion.

San Diego Zoo Global has joined the Roundtable on Sustainable Palm Oil (RSPO), and has been working with other North American zoos and RSPO stakeholders to strengthen and improve its efforts to move the palm oil industry toward sustainability. Along with other members of the Association of Zoos and Aquariums (AZA), the accrediting body for North American zoological institutions, we are exploring ways to ensure the preservation of biodiversity in areas impacted by oil palm.

Today, on World Orangutan Day, the AZA has announced its support for the development of a sustainable palm oil marketplace.  AZA member zoos, including San Diego Zoo Global, collectively educate and entertain 180 million guests each year. That is a significant audience that can help push for change that will “break the link between palm oil and deforestation,” a move necessary to preserve orangutans and other wildlife into the future. As RSPO members, SDZG stands alongside the AZA in recommending that North American consumers help to increase the uptake of Certified Sustainable Palm Oil (CSPO) in our supermarkets. Currently, there is more CSPO produced each year than is purchased for consumer goods. Since CSPO is produced in accordance with sustainable principals and criteria as set forth by the RSPO, orangutans would benefit if demand for CSPO were to rise. You can learn more about CSPO, and the product lines containing it, here.

We have a long way to go to ensure that the beautiful, long-haired “person of the forest” remains in wild places in the future. On World Orangutan Day, we ask you to consider how you might actively participate in efforts to preserve our red-haired cousins by beginning your own journey to sustainability. A good first step? Find ways to modify your habits to include more CSPO in your purchases. Together, we can help secure the forest home for the orangutan, and all its jungle brethren.

Suzanne Hall is a senior research technician for the San Diego Zoo Institute for Conservation Research.

 

18

On the Palm Oil Path: A Journey to Sustainability

Making informed palm-oil decisions can help Indah and Aisha's wild brethren.

Making informed palm-oil decisions can help Indah and Aisha’s wild brethren.

When you watch the San Diego Zoo’s orangutans brachiating from branch to branch, it’s easy to picture the movement of wild apes through the canopy of those big trees in Borneo and Sumatra. Watching our sun bear Marcella sleep high in her climbing structure, you can envision a wild sun bear resting up in the canopy close to the fruit of a monstrous tree. There are a number of species that depend on the lush forests of tropical Southeast Asia, and these species are now at risk due to rampant deforestation and loss of habitat. As mentioned in a previous post, The Palm Oil Conservation Crisis, one of the major drivers of that deforestation is unsustainable palm oil cultivation.

The palm oil conservation crisis is a highly complex problem that cannot be solved overnight. However, San Diego Zoo Global has waded into the issue and hopes to contribute to a solution that can preserve forests and the wildlife that depends on them. Our first step was to join the Roundtable on Sustainable Palm Oil (RSPO), a multi-stakeholder organization that has produced a series of criteria aimed at altering the palm oil supply chain to produce a sustainable crop. (See press release Three US Zoos Take Leadership Role in Supporting Sustainable Palm Oil Practices.) The goal of the RSPO is to make certified sustainable palm oil the norm, thus ending the unsustainable practices that endanger forests. The RSPO is a young organization, and though it has made great strides in its 10 years, there is still a long way to go toward ensuring that palm oil is deforestation-free.

This is the reason North American zoos and aquariums are stepping up to address this issue, too. As conservation entities, we want to ensure a wild future for the species many of our guests see at our facilities. I just returned from the first Sustainable Palm Oil Symposium, hosted by the Cheyenne Mountain Zoo in Colorado. Cheyenne Mountain was the first North American zoo to join the RSPO, and in hosting this symposium they helped to facilitate a dialogue among concerned zoos about what we can do, collectively and as individual institutions. We got an on-the-ground perspective from attending NGOs (non-governmental organizations) that work in Malaysia and Indonesia, and this allowed us to have a better understanding of what parts of the industry are likely to be most responsive to our efforts. It was really inspiring to be surrounded by like-minded folks who are as passionate about the palm oil conservation crisis as we are. Zoos around the world are raising awareness of the problem and are trying to encourage the transformation of the palm oil industry to sustainability. At the symposium, we realized that we might wield a powerful voice if we unite in our efforts.

That is very much our goal now. I hope to share with you some of our efforts and accomplishments over the next several months. In the meantime, you can help by supporting the RSPO’s vision to transform the palm oil industry. Think of this transformation as a journey toward sustainability. Zoos, corporations, and even the RSPO are on a journey, each of us in a different place, but the goal is clear. San Diego Zoo Global supports those companies that are making progress toward a sustainable palm oil industry. We encourage you to support the RSPO and those RSPO-member companies that are taking steps along their journey to sustainability, too.

Suzanne Hall is a senior research technician for the San Diego Zoo Institute for Conservation Research.

3

The Palm Oil Conservation Crisis

Sun bears are the smallest of the bears, but they face a big crisis.

Sun bears are the smallest of the bears, but they face a big crisis.

The San Diego Zoo is home to a pair of Bornean sun bears, Marcella and Francis. Sun bears are the smallest of the eight living species of bear and are well adapted to life in their native jungle home. Being small and light makes it easier for them to climb, an important behavior when the trees in your forest can stretch as tall as 80 meters (more than 260 feet), and the fruit they bear is held aloft. If you need to eat, you need to climb! Sun bears have other adaptations for climbing, too: claws to dig into the bark and bare paws to reduce slipping as they ascend or descend. But these physical and behavioral features aren’t put to good use if their jungle home is denuded of trees. Unfortunately, sun bears have been losing trees, and habitat, to palm oil cultivation.

Have you heard about the palm oil conservation crisis? A major driver of deforestation on a grand scale, unsustainable palm oil cultivation poses a threat to plants and animals that live in the tropical regions where it grows best. In Malaysia and Indonesia, where about 90 percent of the world’s palm oil is grown, ancient forests are cleared to make way for new plantings. This eliminates habitat for the vast array of species that call those forests home. Orangutans, tigers, sun bears, hornbills, tapirs, pangolins, orchids…all are increasingly at risk due to the continuous expansion of the palm oil industry. In some cases, this expansion threatens species with extinction; orangutans, for example, are found only on the islands of Sumatra and Borneo, where palm oil cultivation is firmly entrenched. If we can’t put a stop to the unchecked deforestation resulting from farming this commodity, the estimated 50,000 remaining wild orangutans there may someday soon cease to exist.

Why is the palm oil industry growing so rapidly? It’s primarily because the human population is growing, and with it is an increasing need to supply us with food and materials for our daily lives. To that end, oil palm is an extremely versatile crop and can be used in a wide array of products, from food items to bath and hygiene products to biofuels. As a result, palm oil or its derivatives are an ingredient in about 50 percent of the products on the shelves in a typical US supermarket. Everything from sodas to soaps, from peanut butter to packaged cookies, from toothpaste to dinner rolls…all might contain palm oil.

But palm oil is not all bad. For one thing, it’s a very efficient crop to produce. An acre of palm oil plantings produces 4 to 10 times as much oil for sale as other options like soybean or sunflower oil. Palm uses less land to create a volume of edible oil for human consumption than any other choice. This is an important reason why boycotting palm oil is not a good conservation solution; to boycott is to simply push the land-clearance problem off to some other commodity. It only takes a little effort to uncover how the growth of the soybean industry in South America has created a conservation crisis of its own. Thus, avoiding palm oil in favor of other options does not avoid putting biodiversity at risk. Another factor to consider: palm oil has elevated the lives of millions of Malaysian and Indonesian families, and as many as 30 million families worldwide are economically dependent upon palm oil for their livelihoods.

So how do we North Americans, and conservation organizations like San Diego Zoo Global, begin to address this complex issue? In my next post, I will explore this topic in depth and share with you the actions we are taking. As you learn more about the palm oil conservation crisis, we hope you’ll be inspired to take action, too. In doing so, we can preserve some of those big trees for future generations of wild sun bears like Marcella and Francis.

Suzanne Hall is a senior research technician for the San Diego Zoo Institute for Conservation Research. Read her previous post, Xiao Liwu: Weaning Wrap-up.

262

Xiao Liwu: Weaning Wrap-up

Xiao LiwuLate last week, we separated Xiao Liwu from his mother for the last time. He remained in the main viewing exhibits for a few days while Bai Yun was shifted out of the area so that they were not across a door from one another. We have found in the past that in the first few days post-weaning, the cub can be quite vocal, calling for mother as it wanders about. This can arouse a response from Bai Yun; therefore, we find it best to put some distance between them to allow our adult female to remain relaxed.

As anticipated, our littlest bear has shown some tendency toward wandering and vocalizing in the last few days. This is normal. As mentioned in a previous post, the cub is always the one most unhappy about the separation and would prefer to prolong his or her relationship with momma bear. The lure of a constant companion, playmate, and milk source is strong! Her absence from the cub’s life is something the youngster clearly responds to. However, past cubs seem to move on from their discontent within about a week or so, and we expect Xiao Liwu will follow suit.

For her part, Bai Yun does not seem to reciprocate the sentiment that “absence makes the heart grow fonder.” Keepers have reported that she is doing very well post-separation. The only restlessness observed with her are those typical of food anticipation, the same bouts observed when the cub was with her daily. Otherwise, Bai Yun is very focused on priority number one: her bamboo and other food. For our matriarch, it’s business as usual. Her job of cub rearing now done, she appears thoroughly content.

Xiao Liwu has been shifted off exhibit to the upper bedroom area where he is closer to his keepers. This is beneficial to the little bear, as the keepers are poised to fill some of the social void left by his mother’s absence. Already, they have had nice sessions with him during which they have been able to hand-feed him apple slices and offer him back scratches. The apple slices are a small victory because, as you may recall, he has been unwilling to eat anything but bamboo to this point. Having a food source over which the keepers can bond with the youngster will enable them to build a stronger relationship. These bonding sessions become an important foundation for future training and husbandry that requires cooperation and mutual trust between keepers and animal.

While Xiao Liwu will be off exhibit for some time to facilitate his keeper-bonding experience, there is a silver lining for some of our panda fans. Patriarch Gao Gao has been shifted back to the main viewing area, where he will remain for the next few months. When you observe the bears, you may notice that both Gao Gao and Bai Yun have small shaved patches now, as both underwent routine veterinary check-ups at the end of last week. With that out of the way, and weaning complete, our panda facility will now settle into a new routine that will be the status quo for the near term.

Suzanne Hall is a senior research technician for the San Diego Zoo Institute for Conservation Research. Read her previous post, Weaning Xiao Liwu: Leafy Greens.

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Weaning Xiao Liwu: Leafy Greens

Xiao Liwu is surrounded by leafy greens.

Xiao Liwu is surrounded by leafy greens.

After many days of short separations, giant pandas Bai Yun and Xiao Liwu were doing well. Both bears had a few hours each morning to be on their own, and both spent that time eating heartily. Reunions between them at the midday feed were non-events. Although occasional nursing bouts were observed, it did not appear that the frequency of nursing had been accelerated. Further, the duration of observed nursing bouts was very short, lasting only about two minutes. This suggested that either mother Bai Yun’s milk supply had begun to dwindle or that the nursing was more about comfort-seeking than calorie-seeking on the part of our youngster, Xiao Liwu.

Since no other comfort-seeking behaviors had been observed, we opted to move forward with our weaning protocol. Last week, we lengthened the time the two bears are separated. The two are no longer reunited at midday and instead are separate still as they are served lunch. Access to each other is now delayed until the end of the workday, when the last keeper is ready to head home.

Did you notice? Probably not, since the bears showed no overt response to this change. We have only one report of “Wu” knocking on the door that separated mother from son, and it was a brief event. They are both taking this change very much in stride. In fact, by all accounts, Wu seems to be handling this separation better than any of his siblings. He is a very relaxed bear.

I can’t say why it is that he seems so much better able to adapt to the weaning process than his siblings. Perhaps it is because of his penchant for bamboo. He still refuses to eat anything but his leafy greens, despite our keepers’ gallant attempts to offer him something—anything—that he might like as an alternate treat. We know that adult pandas have to spend a lot of time feeding on bamboo to meet their caloric needs. Perhaps Wu is not so concerned about weaning because he, too, is very focused on bamboo feeding. To get his calories, he isn’t relying on carrots and apples and Gao Gao bread and honey-soaked softened biscuits (keepers have been really trying to entice him!), so he has to take in as much bamboo as he can get his paws on, and there is little time to worry about his mother.

In fact, these weaning separations may be helping him to some degree. Our little panda actually gained some weight in the first nine days of our separation protocol. Perhaps having the bamboo all to himself is beneficial to him. It will take some time, and several more weigh-ins, to see if his weigh gain trajectory alters as a result of weaning separations.

In a short time, if both do well, we will be looking to complete the weaning process for Xiao Liwu. Though some of the details have yet to be worked out, be sure that our keeper staff stands ready to provide Wu with the added social support all of our past cubs have needed once he is independent of his mother. All of our previous cubs have incurred a short period of pining for their mother after weaning was complete (generally not reciprocated by Bai Yun, they’d be sad to learn), but perhaps our bamboo boy will pine the least of all. He’s very busy, after all, getting in those leafy greens.

Watch our pandas daily on Panda Cam.

Suzanne Hall is a senior research technician for the San Diego Zoo Institute for Conservation Research. Read her previous post, Weaning Xiao Liwu: Conflict over Calories.

97

Weaning Xiao Liwu: Conflict over Calories

Xiao Liwu nibbles on a bamboo stalk.

Xiao Liwu nibbles on a bamboo stalk.

Over the last week or so, we have allowed our giant panda mother-cub pair access to more space to see what kind of behavioral pattern develops. We’ve watched Bai Yun and Xiao Liwu closely during this time, both with formalized behavioral observations and informal sessions by keepers and staff. What we have seen is rather typical for this stage in their lives together. Bai Yun is food-focused, moving around both exhibits in search of the choicest bamboo and other snacks. Xiao Liwu is also becoming increasingly food-focused, though interested only in bamboo. When he is finished eating, he follows his mother around, like a little shadow.

Interestingly, this cub is not ingesting much kibble or produce. This makes him rather unique among his siblings in that they were motivated to feed on these calorie-dense items. Xiao Liwu, on the other hand, is limiting all of his non-milk calories to bamboo, which makes it that much more important that he gets plenty of his leafy greens. Since he is nursing very infrequently, probably less than once each day, his bamboo intake is meeting most of his energetic needs.

This is where a conflict arises. Bai Yun is quite determined to meet her caloric needs as well, and though she ingests a lot of produce and kibble, she’s also keen to exploit the bamboo resources we provide. Right now, she has a little competition for the choicest bits, and we have witnessed several bouts of wrestling over bamboo between mother and cub as a result. She’ll even steal the cub’s bamboo and hold him at bay, squealing, while she munches on the remnants of what Wu was working on. Though we provide the two bears with plenty of food, sometimes Wu loses out to his mother with respect to the bamboo he wants. Although he can usually walk away and find something else to snack on, we wonder to what degree his ability to meet his caloric needs is inhibited by his mother.

When not feeding, Xiao Liwu moves about the exhibits in fairly close proximity to his mother. Bai Yun, on the other hand, has not been observed following her son. This is a pattern we have observed with past panda cubs. If the little ones had their way, weaning separations would be delayed by months, or even years! Who wants to give up on the milk bar and the built-in playmate? But Bai Yun is less interested in fulfilling these roles as time goes by. Rejection of nursing bouts is something we have seen off and on for some time. And play bouts are not always welcome. For example, we recently witnessed a bout in which Wu bounded onto his mother with a sudden leap, resulting in Bai Yun biting down hard enough on him to elicit a loud yelp. This brought the play bout to a skidding halt, which may have been the result Bai Yun was going for. As this kind of interaction becomes more common, it reinforces for us the importance of considering momma bear in the weaning equation.

The indicators suggest to us that we should move ahead with our weaning protocol. For this reason, you will notice that Bai Yun and Xiao Liwu will now have periods of separation, each one housed in one of the main exhibits for a few hours each day. The bears will be separated in the morning and given their own foods to chow down on. The cub will not have to worry about his mother stealing his breakfast, and Bai Yun won’t have to worry about play bouts interrupting her meal. We’ll bring them back together about lunchtime and repeat the process the following day. We will, as usual, be watching closely to see how the bears adapt. Stay tuned to this channel for further updates as the process unfolds.

Suzanne Hall is a senior research technician for the San Diego Zoo Institute for Conservation Research. Read her previous post, Weaning Xiao Liwu.

54

Weaning Xiao Liwu

Xiao Liwu enjoys a bamboo lunch in his expanded habitat.

Xiao Liwu enjoys a bamboo lunch in his expanded habitat.

When a giant panda cub is totally weaned from his mother in the wild places of China, one of two things likely happens: either his mother runs him off with aggressive behavior, as has been noted with some brown bears, or the mother and cub simply wander away from each other and begin separate lives. Many panda fans worry that that final weaning event is a sudden change for the bears, but in reality it is the culmination of a longer process that begins some months before, when the cub develops his bamboo-feeding dentition.

At about a year of age, the cub’s diet changes from one of 100 percent maternal milk to one incorporating his staple adult food, bamboo. He starts by feeding on small quantities of leaf, mastering the process of chewing and swallowing a solid food. Gradually, the cub ingests more and more bamboo and needs less caloric support from mother’s milk. By the time a final weaning separation occurs, he may only have been nursing once a day, or even skipping days between suckling bouts. The development of this nutritional independence takes time, and thus, weaning is not accomplished overnight.

Xiao Liwu turned 18 months old on January 29, 2014, and we have begun preparations for weaning him from his mother, Bai Yun. Many of you have noticed changes in the access given to our mother-cub unit, as they are now regularly seen exploring both the left- and right-hand exhibits. We have opened the door between these two usually separate spaces, allowing the pair to freely explore either side, moving independently or together as they see fit. This is an opportunity for both animals to become comfortable with the right-hand exhibit, which Bai Yun hasn’t seen in nearly two years; the cub has never experienced it before.

During this period we will be watching the pandas to see how they are utilizing this newly enlarged space. Do they spend more time in close proximity or separate? Does the cub follow his mother everywhere or explore alone? Does Bai Yun seem to move away from her cub when he approaches? The answers to these questions will tell us more about Bai Yun and Xiao Liwu’s readiness for weaning and will inform our decision-making as we move through this process. We aren’t in any rush here.

The weaning period is sometimes a difficult one for our blog readers and panda fans. There is often concern about the well-being of our bears during this time. Bear in mind, however, that a zoo setting is unlike a wild one in that there are barriers to animal dispersal. Simply put: our animals reside in enclosures, and they are not free to wander away from each other as they might in the wild. We have to help them adhere to their natural tendencies by opening up new spaces.

By making changes to the access our bears have to the spaces around them, and to each other, we are facilitating a natural process that is taking place in wild habitat even as we speak. In doing so, we are respecting the health and well-being of both mother and cub, guided by the best practices that biology, science, and husbandry allow.

I will update you periodically as to the status of our weaning process. In the meantime, I encourage all of our newest panda fans to read up on past weaning events with other panda cubs, in blogs such as:

Weaning Panda Cubs

Weaning Zhen Zhen: And So It Begins

A Big Step Forward

In these, you can find more details about what we know about this period in a panda’s life and the importance of remembering that this is not just about the cub but also the mother. You can get a flavor for how the process unfolds and how past cubs have responded to our weaning protocols. After eight years of blog-writing, our panda archives contain a wealth of information that you can access to learn about this and any other panda-specific topic you might be curious about.

One final note: To make room for our mother-cub pair and changing needs, we have moved Gao Gao to our off-exhibit area. You may see less of him on Panda Cam, but he is still here, happily munching away on bamboo and getting lots of attention from our staff. He won’t be back on exhibit again for about a month, as the weaning process will be focused in the main exhibit spaces.

Suzanne Hall is a senior research technician for the San Diego Zoo Institute for Conservation Research. Read her previous post, Yi Lu Ping (Have a Good Trip), Yun Zi.

200

Yi Lu Ping An (Have a Good Trip), Yun Zi

The time has come to say goodbye to our good-natured young panda, Yun Zi. Yesterday, January 9, 2014. He embarked on his most momentous adventure yet—a move to his homeland. After crating up easily, our boy was loaded into a vehicle for the trip to Los Angeles, where he caught his flight to China. Thanks to the diligence and careful planning of our staff, he is well prepared for his journey.

The keepers worked to ready Yun Zi for all of the transitions he is about to make. He began crate training some weeks ago, getting used to the transport crate he will live in for a few days as he hops across the pond and heads up to the mountains of his ancestral homeland. As anticipated for such a smart and easy-going boy, he adapted to his new crate easily, spending time feeding inside it and accepting treats from his keepers through the openings of the crate.

Yun Zi Throughout the Years

Yun Zi Throughout the Years

Keepers have also been preparing him for the dietary transition he will undergo. In China, the pandas are not fed the low-starch, high-fiber biscuits and kibble they are used to getting in San Diego but instead receive a specially made formulation of bread that is foreign to our bears. Our keepers have access to that bread recipe and for some time have been whipping it up in our on-site kitchen so that Yun Zi could adapt to this new culinary staple. Thankfully, he had taken to the new bread, perhaps better than any of our returnees ever had.  This means dietary changes in China won’t be a big deal for our boy.

Since he is traveling in winter, staff wanted to prepare Yun Zi for the big change in temperatures he will experience. Keepers had been fattening him up a bit, and he has little rolls of flesh that will serve as extra insulation against the cooler mountain air. He looked nice and robust.

Staff has also prepared videos to leave with Yun Zi’s new Chinese handlers that detail aspects of the training he has received. This will help his new keepers to better understand the commands he has been taught, and, hopefully, will enable them to continue to use his training to facilitate future husbandry and veterinary procedures. Our video contains shots of Yun Zi sitting quietly while having his blood drawn, for example; his training allows this procedure without the use of anesthetic. This is a highly desirable, low-stress way to get biomedical data from him, and we wanted to be sure his new handlers are aware of his capabilities.

Yun Zi isn’t traveling alone on this voyage. He is attended by his primary keeper, Jen, who has been with him from birth. She had been actively engaged in his training, both during and prior to his preparation for departure to China. Yun Zi knows and trusts her, and this will be a comfort to him on his journey. In addition, a veterinarian is accompanying our boy on his flight, should there be any medical concerns to address. We anticipate that will be unlikely.

On Wednesday, the keepers began preparing his food bundles for the trip, and I know they were selecting choice bamboo culm to keep him content on the flight. Jen will ensure he receives regular munchies throughout the trip and will regularly refresh his water and clean up his crate to keep him comfortable. All of the plans and preparations are in place.

All that’s left now is to wave goodbye. 

Farewell, Yun Zi. You were a fun and exciting part of our panda research program. Even from far away, you will always be a member of our San Diego Zoo giant panda family. Yi lu ping an.

Suzanne Hall is a senior research technician for the San Diego Zoo Institute for Conservation Research.

 

868

Prodigious Panda Proceedings

Being a panda mother is hard work! Bai Yun takes a well-deserved nap.

Being a panda mother is hard work! Bai Yun takes a well-deserved nap.

Monday was an exciting day for North American zoos holding giant pandas! We are thrilled for our colleagues at Zoo Atlanta, who welcomed not one but two panda cubs as their hero mother Lun Lun gave birth. As a twin birth had not been witnessed in the US in a while, this occasion is especially momentous. We have our fingers crossed that things continue to go well for the Atlanta bears and staff in the next few critical days.

Twinning in giant pandas is an issue of interest to us, because although females give birth to twins nearly as often as they have singletons, the giant panda mother appears unable to successfully care for two cubs simultaneously (see Pandas: Are Two Better Than One?). While there are a few anecdotal accounts of finding panda twins of significant age in the wild, in most cases these reports are not well substantiated. A female in a Japanese zoo several years ago successfully reared twins, but she was the fortunate beneficiary of a lot of support from the zoo staff. Keepers hand-fed her at times or took her cubs to an incubator from time to time to allow her to rest. While her case offers a glimpse into the possibilities for twin rearing in panda mothers, it is not comparable to the solitary effort required by a free-ranging wild panda mother.

Panda mothers in Chinese breeding centers have allowed us to watch a variety of their responses to a twin birth. Many mothers initially do try to care for both cubs, cradling and grooming their twins for a few hours or days before ultimately giving up and rearing only one. Some females don’t put any effort into caring for both cubs and instead focus on one from the very start. It would be interesting to follow those mothers through multiple years to see if their strategy changes with each twin birth or if you can predict that a female who has attempted to rear twins once will do so again in the future. As of this writing, I do not know the answer to that question. What we can say is that at some point, a mother of twins has to make a choice about which cub she will care for and which will be abandoned to its fate.

The San Diego Zoo’s Giant Panda Conservation Unit has invested considerable time in trying to understand what factors play a role in determining which twin cub a panda mother selects for nurturing. Is it the birth order that matters most? Or do mothers choose larger, more robust cubs? Perhaps they prefer a specific gender of cub? Is the mother’s decision influenced by whether or not she is a first-time mom? Our work is using data compiled from Chinese breeding centers and twin births around the globe throughout the known history of giant pandas in captivity. Soon we will be able to answer several of these questions.

Our Chinese counterparts have demonstrated repeatedly that with twin swapping and good nutrition, a rejected panda twin is not necessarily fated to die but instead can embark on a healthy, productive life. We know that Lun Lun’s offspring will be offered great care, whether from mother bear’s embrace or from their well-trained staff while in an incubator. With a little luck, we may all get to watch a charming pair of panda cubs grow up right here in North America—and that would indeed be a milestone for our panda population.

Suzanne Hall is a senior research technician for the San Diego Zoo Institute for Conservation Research. Read her previous post, Xiao Liwu: Meeting those Milestones. Watch our pandas daily on Panda Cam.

145

Xiao Liwu: Meeting those Milestones

Mother and cub engage in a wrestling session.

Mother and cub engage in a wrestling session.

I have had the opportunity to observe panda mother and son, Bai Yun and Xiao Liwu, quite a bit lately, and I have noted that the cub’s behavioral development appears right on track with respect to his siblings. He is at an exciting age for a panda, a time when the learning curve is a little less steep than it was a few months back, and Xiao Liwu is busy exploring every nook and cranny of his environment…when he isn’t napping, of course. Babies do need their rest!

One of the major milestones our little boy is working on is bamboo feeding. Now, he isn’t yet ingesting it as a food staple. Xiao Liwu still relies on mother bear to provide him with milk to satisfy his caloric needs. But he is learning to handle the leafy material, working it in his paws and practicing with his pseudothumb. The cub spends time mouthing bamboo, stuffing a leaf or two in his mouth and chewing, chewing, chewing…until he ultimately spits it out. No doubt there has been some incidental ingestion of the plant, but as the necessary teeth are not all in place yet (that occurs at about 12 months of age), he doesn’t have the tools with which to begin efficiently processing bamboo. That time is coming soon, however, and in the next few months, we will begin to see him regularly ingesting the plant that will become his staple dietary ingredient.

Play is an important part of his behavioral repertoire at this time. Play is often scientifically defined as an apparently purposeless behavior, because it doesn’t provide an obvious payoff. It doesn’t help a panda obtain food, or secure a mate, or ensure safety and survival. Yet for a cub, play is an important part of healthy development. Locomotory play, including frisking about on the ground and twirling around in the trees, helps to develop strength and coordination as the cub learns to control his growing body. Object play allows the cub to effect control over elements in his environment, influencing the development of his confidence and coordination. Social play teaches him the nuances of interacting with others of his species, including how to read and deliver appropriate social cues. Yet this “purposeless behavior” may only seem purposeless in the immediate sense. There are payoffs down the road, associated with neurological development and perhaps even learned behavior.

Play is a behavior that peaks in the late juvenile period before bottoming out as the bear becomes an adult. Interestingly, the juvenile period is also the time of greatest growth of that portion of the brain known as the cerebellum, an area that plays a role in coordinating smooth motor function. Adulthood, as we all know, is the time when we take on the mantle of caring for ourselves, and for the panda that means spending most of its waking hours foraging and feeding. There must also be time for procuring a mate or rearing young. There is little time for frivolity, and efficiency matters. By the time a mammal has reached adulthood, its neurological development is complete, and it can now reap the benefits of what its brain has been trained to do.

But while scientists are still unraveling the mysteries of the function of play, you can simply witness the fun as Xiao LiWu continues on his developmental journey. Enjoy it while he is little, either in person or on Panda Cam, because one thing this scientist can tell you definitively: watching that panda cub play is absolutely charming!

Suzanne Hall is a senior research technician for the San Diego Zoo Institute for Conservation Research. Read her previous post, Through the Bear Lens.