Monday morning, February 16, was the first morning we lengthened the separation time for giant pandas Bai Yun and Zhen Zhen to approximately 18 hours. We separated the bears about 4 p.m. Sunday, February 15, as has been the case for more than a week. However, on Monday we waited to reunite the two bears until about 10:15 a.m. Zhen has been used to seeing her mother again early in the morning, and the change dawned on her slowly yesterday.
Initially she was nonplussed and spent the early morning hours feeding on bamboo and playing with three Boomer balls the keeper had placed in her exhibit. At about 8:30 a.m., when the hearing study training began with Bai Yun, Zhen heard the clinking of gates and the voices of keepers talking with Bai during her session. It must have suddenly occurred to her, “Hey, I am usually with momma before this happens,” and she began to try to peek down the corridor and wait at her keeper door for access. But it wasn’t time yet.
The falling rain did not deter Zhen from slow motoring about her exhibit, checking her doors repeatedly and sitting patiently atop her den or near the corridor. More clinking gates signaled that Bai Yun had now been released into the exhibit next door, and still the gate had not opened. Slowly, Zhen started getting more wound up, moving faster about her exhibit, climbing and generally foregoing the chance to rest.
Bai Yun, however, showed no sign of concern. On exhibit, she happily munched bamboo, never once checked the separation gate, and barely paused at any point in the morning to look about her. In fact, staff reported she had one of her best-ever training sessions that morning: clearly she is not losing sleep about the separation from Zhen.
Once reunited, Zhen mugged her mother. Within a few minutes of the introduction, Bai Yun relented to the gales of Hurricane Zhen and led her into the den, out of the rain, for a nursing bout. Satiated and satisfied with her mommy time, Zhen then climbed a tree and slept on her own for a period.
We anticipated that this step in the weaning process would be one of the most difficult for our littlest panda. Her siblings also started to really feel growing pains at this stage, and so we knew Zhen would likely follow suit. But the real key to all of this is Bai Yun.
As I mentioned in previous blogs, we don’t know for certain how the weaning process is achieved in the wild. We believe it to be a largely mother-driven endeavor, with mom either wandering off, denning up, or driving her cub away at some point. One thing we can say for sure: it doesn’t matter if Zhen is 8 months or 18 months or 28 months, she wouldn’t leave her mother if it were up to her. This is why we expect some discomfort from her during the weaning process. But Bai Yun is a different story. When she shows us she is relaxed and taking this all in stride, then she is telling us SHE is ready. In the wild, she would be content with taking the steps necessary to separate from her youngster. And this is our barometer that the timing is right.
I have read several of your comments on the blogs in recent weeks and know that many of you have expressed sadness over the weaning. Like you, I feel a little for Zhen when I see her appearing anxious. As a staff, our concern over her well-being is one driving force behind our intensive effort at this time: we are monitoring her closely, watching both Bai and Zhen overnight with videotape, assessing their reactions on a daily basis. Keepers are ensuring Zhen has access to high-quality bamboo, enrichment items, and their attention. But we recognize that there is no way around Zhen feeling a little confused during this time.
However, Barometer Bai Yun informs us that we are moving forward in the right way and at a pace that is comfortable…for HER. As a mother myself, I understand the sense of relief when a youngster moves on, grows up, takes the next step. Bai Yun’s current demonstration that she is content is an important indicator that we should all factor into the equation.
Some of you have asked about comparisons to Wolong cubs and their sociality post-weaning. In Wolong, cubs are weaned very early, at about six months of age. They are then placed in groups with other youngsters to fulfill their social needs, a very smart way to handle motherless youngsters. Zhen, like our other cubs, has been with her mother a full year longer than those Wolong cubs and is better able to adapt to a life on her own as a result.
We recognize, however, that subadult pandas can be more social than adults. In the wild, young male bears can be found in proximity to older males, a type of social shadow that the older male does not feel threatened by. Even the young subadults seen in trees at mating sites may be drawn there by the ruckus of a female in estrus and her entourage of males. We try to offer social opportunities to our subadults in the form of increased keeper interactions, training sessions, and howdy gate opportunities when possible. To that end, Su Lin and Zhen may one day meet across a gate. It’s also the case that our littlest independent pandas often seem drawn to the public viewing areas, enjoying the daily litany of admiring guests who come to see them. We will accommodate this inclination as well, when the time is right.
Zhen will soon be pulled off exhibit, when we are ready to make the separation between mom and cub final. For a time she will live behind the scenes, soaking up keeper love and residing far enough away from mom that it will not be a tease to her that mom is in proximity. Enjoy these last few days of the two together, and celebrate that she will soon be on her way to adulthood. Like Su Lin and her other siblings before her, Zhen will be well cared for as she makes this important transition.
Suzanne Hall is a senior research technician for San Diego Zoo Conservation Research.