Update on the Andean Bear Cubs at the Zoo

Just a few weeks after Andean bear cubs were born at the National Zoo, they are still spending time with mom Billie Jean in the den (much to our dismay, since we won't be able to tell their genders until they come out some time in the next month). But the keepers at the National Zoo have been keeping tabs on the twins via television and audio monitors. We checked in with Tracey Barnes, one of the bears' keepers, to see how Billie Jean and her babies were doing.

What was it like seeing the birth of those bear cubs, but not being able to touch them?

It’s a thrill, but it’s a little frustrating. Because I was here the morning they were born, I spent the night and I’d been watching around the clock and all of the sudden around 8 in the morning we started hearing squealing and realized we had a cub.  And of course the first thing you want to do is run back there and look. But having worked with bears for a number of years I know that things can be very touch and go with bear cubs for the first few weeks, and stress plays a major part in their survival. You don’t want the mother to be stressed: you want her to be in a nice, dark, quiet place. You have to pretty much fight every instinct you’ve got, knowing it’s the best thing for the bears and just let them be. We’ve happily been able to watch them from the monitor and we have audio set up there. So when I'm in the keeper office, I can hear the cubs nursing and squealing. As it turns out that, in itself, is good enough for me.

When the cubs actually do leave the den, will they instinctively explore on their own, or will the mother take them out?

It can work one of two ways. Sometimes the mother will choose to bring them out before they can walk, merely by bringing them up by the scruff of the neck—similar to what you’d see with cats. That doesn’t look like it’s going to happen with B.J. I can never say never, because animals continue to surprise you, but she hasn’t been inclined to bring them out just yet. What I experienced with our last cub birth is that once the cub was up and moving, Mom spends a lot of time trying to come up with ways to keep them in the den. Eventually went out and so she allowed him to come out very close to her, between her front legs, or right beside her, or on her back. So I’m anticipating that’s what will happen to BJ and her cubs, they will all three come out very slowly together.

When the bear cubs are first born, they’re hairless and toothless. What do they look like now?

We noticed they were really looking dark, so that indicates their fur has pretty much filled in now and you can see light spots on their face where their snouts are. So on the monitor,  you can make out the front end from the back end. Now they’ve gone from originally looking like little sock rolls to looking like bear cubs: You can see their faces, their legs. We watched one of them stand up. They’re starting to get their legs under them.

Are they still in the nursing stage?

They’ll nurse for the better part of the year at least. There’s a good reason for that: Bear milk is very nutritious, it’s very rich. When you compare it to human milk, which has a fat content of four percent, bear milk has a fat content of 46 percent, which is one of the highest in the animal kingdom. They’ve got a very nice supply of nutrition coming from Mom and we can hear them humming, which is the sound they make when they’re nursing. So we know they’re nursing well and that they’re happy. They are fairly advanced, however, when they come out of the den for the first time. They’ll sample food right away. They’ll still be nursing but they’ll already be capable of starting to nibble on solid food. Bear cubs are the same in the wild. Once they leave the den, they can start foraging in the wild right next to Mom, but they’ll continue to nurse.

What has made it so hard for these bear cubs to survive in captivity?

really needs dark and quiet and we’re very lucky we’ve been able to do that at the National Zoo. But all zoos have to kind of work with the constraints they have in their facility. So that could be part of the problem, but it’s hard to say. Even in the wild bear cubs are very helpless at birth. They can easily die from infection; if the mother is stressed that can cause her to reject them; sometimes the mother isn’t producing milk. There are a myriad of reasons and it’s never the same from birth to birth. It’s unique to each birth and unique to each zoo, and we feel really lucky that right off the bat we had successful twins.

The mother and cubs are in seclusion in their den at the Zoo and not on view to visitors. No photographs are yet available either, so as to not disturb them. However, visitors can catch a glimpse of what's going on inside the bear den via the Zoo's animal cam.

Erica R. Hendry | | READ MORE

Erica R. Hendry is the innovations reporter/producer for Smithsonian.com