Springtime for Polar Bears


Logs of all sizes are one of the enrichment items keepers provide for our polar bears.

Another breeding season has come and gone for our polar bears. Chinook and Kalluk bred this year in February, so the waiting game begins once again.

Sometime in late September or early October Chinook will be brought inside and given access to her private air-conditioned den where she will hopefully rear her first cubs. She has already started to show signs that she wants some “alone time,” so on most days you will see her on exhibit in the morning and in the “polar bear penthouse” in the afternoon where she has her own private pool! If you take a look behind the exhibit on the far left you may be able to get a glimpse of her through the pine trees.

Kalluk is just now starting to come out of his annual post-breeding season malaise and is once again playing with his sister Tatqiq. They have been wrestling both on land and in the pool!

The keepers are hard at work providing as much novel enrichment as possible for the bears. If you have been watching our Polar Bear Cam recently, you may have seen interesting things like a log-and-palm-frond shelter, foraging piles, and burlap sack “seals”. The bears love it when they tear into a “seal” and find things like favorite toys, bones, and melons. In the near future we hope to bring in a crane to move around the large logs and root balls in the exhibit as well as bring in new furniture. It is the goal of the Polar Team to provide a dynamic and ever-changing space for our bears. Also, keep your eyes peeled for a snow day sometime in the next couple of months!

We invite you to come down to see what the bears are up to!

Matthew Price is a senior keeper at the San Diego Zoo.


Polar Bears: Keeping Cool

Tatqiq knows how to stay cool!

The summer of 2012 will go down in history as one of the hottest on record. This brings lots of questions as to how polar bears at the San Diego Zoo can live in even the milder heat here. The first answer: our 130,000-gallon (490,000 liters) pool is chilled to under 55 degrees Fahrenheit (12 degrees Celsius). The shallow area allows the bears to lie down and even sleep if they choose. The mid-range allows for great soaking opportunities, and the 12-foot (3.6 meters) deep end allows for complete submersion and swimming. On most summer days, the breeze through the exhibit comes right off of San Diego Bay, so it is a cooling sea breeze. Throughout the exhibit there are numerous shaded areas with various bedding materials for the bears to sleep on. There is also a portable air conditioner we can direct up by the back area where they especially like to sleep. Inside the bedroom area, we also have air conditioning to take the heat out if absolutely necessary.

The real reason we can keep our polar bears comfortable, even on the hottest days, is by limiting the amount of fat they have on their body. For polar bears to survive the cold of the Arctic, they must build up at least 4.5 inches (11 centimeters) of fat over their body. They do this by eating seal blubber. A polar bear’s diet is 90 to 95 percent fat in the wild. They are so specialized for eating fat that they metabolize close to 90 percent of what they eat into body fat.

Here in San Diego, our nutrition staff has developed a diet that is 5- to 10-percent fat, so our polar bears get what they need for good health but not for bulking up for a cold winter. All of our bears would weigh much more than they do now if they had those fat layers. Kalluk, who is now over 1,100 pounds (500 kilograms), would probably be closer to 1,600 pounds (725 kilograms)! When polar bears put fat on, it goes first on their belly to protect their core. Do you know that the body temperature of a polar bear is the same as ours? 98.6 degrees Fahrenheit (37 degrees Celsius)! The fat then layers over their bum and spreads out over their body.

Here’s one way to tell our three apart: When you look at them in profile, Kalluk and Tatqiq have a rounding of their bellies, but from the top of the hip to the tail it’s flat. Since we keep a bit more weight on Chinook (just in case she might be pregnant), her belly is nice and round, and her bum matches! And let’s not forget the CARROTS! Polar bears get little to no nutrition or calorie from vegetation. Our three can eat as much as they like and not put on a pound. Currently, they get 100 pounds (45 kilograms) a day between them that gets chewed, swallowed, slightly steamed in their bellies, and then eliminated. As keepers, we call that job security!

One problem with warm weather we seem to be challenged with this summer is the algae growth. Our water quality team constantly monitors the pool’s water for safety and cleanliness, but algae is airborne until it finds moisture. With the warm temperatures and direct sun, we’re experiencing quite a bloom. We add rock salt to help, but, unfortunately, some of it has imbedded into Tatqiq and Kalluk’s hollow hair shafts. It sneaks in through the small breaks in the shaft formed by grooming. This won’t harm them in any way, but it’s pretty embarrassing to have polar bears with a greenish hue! Our polar bears were once famous for being green when they lived in the smaller grotto exhibit decades ago. Since moving to this exhibit in 1996, we’ve not had any “greening,” until this year. So in the next few days we’ll be hosting “spa days” for a purpose—mineral salt-water soaks for all! Chinook and Tatqiq have always been pros at the soak; Kalluk will be challenging, since he thinks it’s only about dive bombing his sister and then slurping the saltwater off his giant paws. He’s got 13 inches (33 centimeters) on each foot to slurp from!

Summer brings great fun but also great danger with the dry heat. It is sad to hear of fires burning across our nation, so many losing their homes. It’s heartbreaking to lose so much; thank goodness for insurance. In the past few decades, polar bears have lost their ice homes in an area the size of Texas and Alaska combined. We now see forest fires burning in the Canadian tundra, the place with one of the highest densities of polar bear denning, the place where our beloved Chinook was born. What insurance do they have? They have us. We must be the guardians of our planet. We must continue to reduce our greenhouse gas emissions, especially when it seems there is no hope. We still know it can be done. We must be the insurance to protect and insure that our children and grandchildren will still have the opportunity see the magnificent polar bear roaming our planet.

JoAnne Simerson is a senior keeper at the San Diego Zoo. Read her previous post, Polar Bears: Breeding Season.

Watch the polar bears daily on Polar Cam.


Polar Bears: Back to 3

Chinook enjoys some ice time in July.

Over the past week, Chinook has been more active and has been spending lots of time outside in our polar bear management yard instead of her bedrooms and den. On this past Sunday, we removed the den, and she seemed not to care. So this morning we reintroduced our fabulous threesome! After a brief greeting, all three settled on exhibit: Chinook in the mulch by the road, Kalluk on the point, and Tatqiq at the edge of the pool. All seem to be pleased with each other’s company. Chinook did go up to the doors after 30 minutes to see if we were around, but after sniffing and listening she went back out to her mulch bed.

The immediate future will be about continuing the ultrasound exams for a few weeks just to see any changes. Then as we approach the end of winter, we expect to see Kalluk’s behavior change, letting us know breeding season will be upon us shortly, and then. . .we all know the routine. So uncross you fingers and rest your hopes, at least until next fall!

JoAnne Simerson is a senior keeper at the San Diego Zoo. Read her previous post, Polar Bears: No Easy Answers.


Polar Bears White and Brown


It has been a really busy beginning to 2011. Chinook let us know in December that cubs were not on the way (see post Polar Bears: What December Brings), and she was ready to join her buddies Kalluk and Tatqiq in life at Polar Bear Plunge. As keepers this is sometimes a worrisome time: not sure if the relationships from the past will still be there. Of course, after some initial greeting time, the famous three were up to their old antics. It is also the time of the year that the girls seem to be best friends, and Kalluk spends more time practicing his basketball skills!

Is that really you?

We used some of this time to do annual maintenance on the front pool: steam cleaning, replacement of lights, fresh mulch, etc. This meant that all three bears would be inside the bedrooms and yard—all together! With great affection, you must know that these three are beyond messy! Besides providing them with loads of boxes, burlap, and hay, they also felt it necessary to bring in fresh mulch from the yard into the bedrooms and the indoor pool—every day! Once back out to the main exhibit, Chinook definitely showed off that she truly is the queen of the mulch roll! Good thing Kalluk has a good sense of smell, as it appeared he was wondering where the brown bear came from!

Recently, Kalluk and Chinook have begun their great flirtation we see around breeding time. It seems a bit early this year, but they seem to be greatly enjoying each other’s company more than past years. Could this be a good sign? Tatqiq is now a bit of a loner and just stays away when the three are together. She has learned that this, too, will pass, and soon her silly, amorous buddies will be interested in playing again.

We are still collecting fecal samples from Chinook in hopes of being able to get a hormonal assay to determine pregnancy; we are now also collecting urine samples. Any information we can achieve will help us better understand polar bear reproduction.

We have also placed on the Wish List a request to give the polar bears snow. Take a look! If we reach our amount, we’ll be sure to give you notice to watch the fun on Polar Cam. Until then, keep doing your part to conserve and help the polar bears in the Arctic. Unfortunately, for all our cold weather down here it has been a very warm winter for our ice bears of the north!

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


Brother and Sister Bear

Well, it’s going on two months since I’ve returned to work from maternity leave. I can’t believe how fast time goes by. Thanks to everyone who sent their warm wishes and kind words. As much as I love being a mom, this was it for me. I now have one of each: a boy and a girl. I sometimes wonder what their relationship will be like, and I refer to another brother and sister pair I know, Kalluk and Tatqiq at the San Diego Zoo’s Polar Bear Plunge.

Speaking of time flying, they are coming up on their eighth birthday. It seems like only yesterday that these two cubs (12 and 16 pounds) came into our lives. I remember how dependent they were on each other. They were not comfortable being separated for any length of time, so we allowed them to stay together to help them cope with new experiences.

This made feeding time a challenging experience. They were weighed daily and fed a certain percentage of their body weight in formula. Even though they relied on each other for comfort, they still could get competitive over their food. We had quite the system down that allowed us to feed them together and had them finishing at the same time so there were no spats.

When it came time to investigate new experiences, Tatqiq always seemed to lead the way, with Kalluk following behind. Once Tatqiq gave her stamp of approval, then Kalluk was more apt to join in. If there was ever something they were unsure of, they stuck close together as if they were glued side by side. This carried over into bedtime, and they would sleep together, sometimes using each other for pillows.

Over the years they have grown up and asserted more independence. Even formed different relationships when Chinook was introduced. It’s not uncommon to see them off doing their own thing. But even after eight years, the sibling bond is still strong. They still enjoy playing together; many a morning I’ve come in to find them wrestling or taking a swim in the pool. Or sometimes I find them curled up in the same pile of mulch. They continue to rely on each other for support whenever either one is unsure of a situation. It’s nice to know you can always count on family when you need them.

Kelly Murphy is a senior keeper at the San Diego Zoo.