Polar Bear Answers

Chinook fishes for lettuce.

Chinook fishes for lettuce.

You have all done great with your ideas for reducing your carbon footprints! (See comments posted in Polar Bear Anniversary and The Polar Bear World.) And you’ve posed so many questions, I’ll try to answer some of them here.

First, let’s talk about polar bear fur. Polar bears are very clean bears! Even in the wild they use snow, kelp, and brush to clean their fur. Here in San Diego they do jump in the pools and then use the mulch to dry off. They also lick their paws and legs to clean them. Often you will see them rubbing their faces and rubbing against the sides of the pool for cleaning. Their fur is a bit coarse and long on the outer, or guard hair, layer. The fur underneath is soft and wooly.

Now let’s talk about some former residents of Polar Bear Plunge. Before Kalluk and Tatqiq moved to San Diego, we had another polar bear pair: Buzz and Neil. They were two males that lived with Chinook and Shikari from 1997 to 2001. In December 2001, Buzz and Neil moved to the Como Zoo in St. Paul, Minnesota. The Como Zoo is now in the process of building a new exhibit for “the boys,” so the two bears were moved to Detroit last April. The boys have been introduced to a young female, Talini, and have had great playtimes together, according to their keepers in Detroit. I did get the chance to visit with them when they first arrived in April, and they looked great! I have good contact with both the keepers in Detroit and St. Paul and always keep tabs!

What’s the story on our current residents? Born in Alaska, Kalluk and Tatqiq’s mother was shot by a hunter. She was wearing a satellite collar at the time, and the cubs were rescued within hours. You might like to know that most of the folks from the agencies responsible for their rescue have come by to visit the siblings and are always amazed at how fabulous and large they have become! We have been really lucky as well because we have formed great bonds with wildlife biologists from Alaska. We now all collaborate on so many projects to help the polar bear!

We have no reason to think that Kalluk and Tatqiq will not be able to live together for a long time. Although we consider polar bears to be loners, they do have a large repetoire of social behaviors and communications, and we have found that siblings in zoos do very well together.

Speaking of Kalluk, he has gotten a bit thinner due to the fact that he has not exactly had his mind on eating much lately. We’re not too concerned, as this is normal for males, and we know our boy can eat when he wants! We don’t know if polar bear cubs are in the immediate future, but Kalluk and Chinook have had some excellent breeding bouts and we are definitely planning on cubs! We are currently building a very small and cozy den inside our polar bear building in the hopes that Chinook may be pregnant. Female polar bears den in very tight quarters with just enough room for mom to turn around. The den is located in an area of the building where Chinook will be secluded from Kalluk and Tatqiq but will allow them plenty of space to come inside as well. Once Chinook shows us she wants that seclusion, we won’t have the three bears together until after the cubs are a few years old!

But before we have any parties we have a ways to go. Polar bears have delayed implantation, and we’re not sure what triggers the fertilized egg to implant or for it to be carried to a successful birth. Another puzzling aspect is that we suspect polar bears can have pseudo, or false, pregnancies. So Chinook may den up but we won’t know for sure until we hear or see cubs. The gestation is estimated to be 195 to 265 days. During the San Diego Zoo’s history of polar bears births, they all occurred from October 24 to December 7. That time frame would be a reasonable expectation. . .but we’ll be ready for any time!

JoAnne Simerson is a senior keeper at the San Diego Zoo.