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.