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Polar Bears

17

Polar Bear Tatqiq Wears It Well

Tatqiq wears a collar

Tatqiq wears a collar for conservation science.

If you visit the San Diego Zoo’s Polar Bear Plunge these days, you might see something new: Tatqiq is wearing a white collar! While Tatqiq seems to be enjoying both wearing this new accessory and the training involved in putting it on and taking it off every day, our motives for having her wear it are focused on conservation science. Tatqiq will be contributing to research led by the U.S. Geological Survey focused on developing a better understanding of the behavior of wild polar bears in Alaska. These data will help us refine our understanding of how sea ice losses driven by climate change will impact polar bears.

The current configuration of the collar is simple: a thick and flexible plastic strap held together with a pair of zip ties, so Tatqiq can remove the collar easily if she wants to. If the collar is pulled, it will immediately loosen and fall off. However, this collar will soon be instrumented with a small accelerometer (the same technology that allows your smart phone to automatically adjust its screen orientation) that will provide scientists with information regarding the behavior of the bear wearing the collar. Because the polar bear’s Arctic sea ice has historically made it near impossible to make direct observations of polar bear behavior in the wild, the data we gain from the accelerometer will provide new insights into their daily behavior, movements, and energetic needs.

Held together with zip ties, the collar can easily come off if needed.

Held together with zip ties, the collar can easily be removed by Tatqiq if it bothers her.

“Radio-collars” have been used to track wildlife for decades and were initially developed to study the movements and infer the behavior of grizzly bears in Yellowstone National Park. These early studies provided wildlife scientists with data that revolutionized our understanding of how individual bears moved about the landscape, and in so doing, helped us develop a much better understanding of what their habitat needs might be.

Since that time, the technology used to track wildlife has changed quite a bit, but the collar itself is still most commonly used to mount tracking devices and other instrumentation. With the advent of GPS collars (instead of VHF transmitters), the precision and quantity of the data we can collect on a wide array of animals has greatly expanded. The data collected by the instrumentation on these collars can also be downloaded remotely and frequently, allowing scientists and non-scientists alike the opportunity to track animals in the most remote corners of the Earth in real time and from the comfort of their own home or office.

While movement and location data are valuable, they only tell us part of the story. By studying behavior, we gain more insight into how animals interact with their environment and why different degrees of environmental change may differentially influence their chances of successful reproduction or survival. While baseline data can tell us about the range of behaviors an animal may engage in under a range of “normal conditions,” data collected under challenging environmental conditions can tell us much about the limits of a species’ ability to cope with their new environment and help us better predict what their limits might be. This work is part of the U.S. Geological Survey’s Changing Arctic Ecosystems Initiative.

We hope the collar...

We hope Tatqiq will help us test this new technology for studying wild polar bears.

The polar bear exemplifies the challenges associated with studying and protecting wildlife in our rapidly changing world. The Arctic sea ice, the habitat that the polar bear completely depends on for survival, is disappearing at an alarming rate. These habitat losses are driving population declines across the polar bear’s range, but some subpopulations are being hit harder than others. For example, recent results published from a long-term study of wild polar bears showed that the Alaskan population of bears from the Southern Beaufort Sea had declined by about 40 percent since the year 2000. Forty percent! That is a tremendous decrease and double the level of the most dire estimates that have come out of the last three decades of monitoring.

Tatqiq has always been a great conservation ambassador for polar bears everywhere. Visitors to the San Diego Zoo who have spent time watching Tatqiq (and Chinook and Kalluk) know that she is playful and engaged and demonstrates a range of behaviors that provide insights into the intelligence of these majestic bears. Now, Tatqiq will be helping us better understand how we can apply technology to better understand the behavior of wild bears. She wears it well!

Megan Owen is an associate director in the Applied Animal Ecology Division, San Diego Zoo Institute for Conservation Research. Read her previous post, Pandas Zhen Zhen and Yun Zi.

56

Well, Chinook?

I snapped a photo of this bear from the Polar Cam. Any guesses as to who looks so relaxed?

I snapped a photo of this bear from the Polar Cam today. Any guesses as to who looks so relaxed?

Polar bears have, what seems to us, a long gestation period. A fertilized polar bear egg doesn’t implant or develop right away. Instead, it implants when triggered by the female’s body condition and environmental factors, most often between September and November. This is known as delayed implantation, an adaptation that ensures cubs are born to healthy mothers at a time of year when their chances for survival are greatest. We are in the middle of that time zone right now with our female bear, Chinook. If a fertilized egg were to implant, the actual fetal gestation would be about 60 days.

Keeper Samantha Marino explained that Chinook is starting to be come interested in using bedding materials and desires more “alone time” from Tatqiq and Kalluk on a more regular basis. Keepers are offering Chinook denning/nesting materials, such as Bermuda grass, burlap, and palm fronds, and allowing her to spend the afternoon away from the other bears. They will continue to monitor this behavior and give Chinook what she needs for a possible pregnancy.

Chinook’s urine and feces are collected and sent to our Endocrinology Lab several times a week to determine if there are any changes in her hormone levels that might indicate that hoped-for cubs are on the way. And currently, Chinook is just on exhibit in the morning; in the afternoon and evening, she gets to enjoy the privacy of the off-exhibit polar bear yard, which includes access to the bedroom area.

We will certainly let polar bear fans know if anything changes, but for now it’s just a waiting game. Paws crossed!

Watch the bears daily on Polar Cam…

Debbie Andreen is an associate editor for San Diego Zoo Global. Read her previous post, Pandas Keep Cool.

51

Scents for Polar Bears

Kalluk thinks snow is the PERFECT enrichment for polar bears!

Kalluk thinks snow is the PERFECT enrichment for polar bears!

Lions and tigers love perfume and giant pandas enjoy the smell of cinnamon, but do the San Diego Zoo’s polar bears get a kick out of scent enrichment, too? Keeper Matt Price explained to me that although our Arctic bruins have impressive sniffers, they don’t go all crazy rubbing around in smelly things like some critters do!

Keepers do have an impressive arsenal of scents on hand for the animals in their care. Various perfumes, essential oils, spices, and even synthetic urine from other species are used from time to time to give our Zoo animals something different to experience, investigate, or delight in. The big cats and pandas roll around in the scent, seemingly trying to spread it all over their body. But the polar bears’ reaction is different: they give the new smell a good sniff and then go on with whatever activity they were doing—no big deal! So instead, Matt or his fellow keepers make a scent trail that leads the bear to a big payoff—an extra-special food treat or new toy. The bear follows the smell to the prize!

There is one type of scent enrichment that DOES get more of a reaction from our polar bears: camel and llama hair. Keepers collect the shed hair and place it in small piles for the bears, who roll around in it with great gusto!

Debbie Andreen is an editor for San Diego Zoo Global. Read her previous post, Gao Gao: Class Clown.

91

Spring Cleaning for Polar Bears

Tatqiq really enjoyed her snow day last year!

Tatqiq really enjoyed her snow day last year!

The San Diego Zoo’s polar bears will be off exhibit through today while we spruce up their exhibit a bit. Our goal is to provide a dynamic environment for the bears. It is quite the undertaking to move around all of those giant root balls and logs in the exhibit, as well as bring in new ones.

We brought in a crane to lift a 5,000-pound root ball from the elephant yard and place it in the polar exhibit. We hope to be able to do this at least two to three times a year to change up the exhibit for our bears. A wild polar bear’s environment is constantly changing due to the movement of the sea ice, and we feel it is important for our bears as well. We want them to have an exhibit and a home that isn’t always the same every time they leave the bedrooms. At this time you will also see a completely empty exhibit pool. All 150,000 gallons were drained so that we could go in to steam clean and pressure wash the entire surface of the pool. This is something we do once or twice a year.

In addition to moving around existing exhibit features and bringing in new ones, we will also be completely changing their exhibit on Saturday, May 17, by bringing in 18 tons of ice that will be run through a chipper to create snow for our bears. They will have a blast sliding down the hills, tunneling through the snow, and searching for things that we have buried. Generally the snow lasts for four to six days, but with the warm weather we are currently experiencing in San Diego, it could be gone in a day or two.

We hope you will be able to join us on Saturday, May 17, either in person or on Polar Cam so that you can witness all the fun before the snow is gone.

The Polar Bear Team

4

Climate Change: Polar bears, Sea Ice, and Beyond

Kalluk enjoys last year's snow day at the San Diego Zoo.

Kalluk enjoys last year’s snow day at the San Diego Zoo.

Climate change is back in the news and, unfortunately, the news has not been good. A number of recent reports indicate that carbon dioxide in our atmosphere has reached unprecedented levels. At over 400 parts per million, we have reached a number that would have seemed unimaginable just decades ago. But while the scale of this problem is immense, the real power for changing the current trend is within each of us. The choices we make—what we buy, how we spend our time—can lead to dramatic differences in our carbon footprint. It is possible to reverse the current trend if we all commit to changing our daily habits.

There is a vast array of information now available that outlines the many-faceted ways that the changing climate will impact people and ecosystems all over the world. From extreme weather to climate warming, the reach of climate change is broad. And the reason our climate is changing is known: human activities have driven the release of unprecedented levels of carbon dioxide into the Earth’s atmosphere. Carbon dioxide (CO2) is a greenhouse gas that effectively blankets the Earth, increasing the amount of heat that stays in our atmosphere. And while we typically associate carbon dioxide emissions with the burning of fossil fuels, such as gas and coal, there are other sources as well that are not as well known. One of the largest contributors to atmospheric carbon is deforestation. Each year, the burning and clearing of tropical forests contributes over 2 billion tons of carbon pollution to the atmosphere.

At the San Diego Zoo, our mission is to connect people to wildlife because that connection can be a powerful force for conservation. I can speak from personal experience as to the power of that connection. Destined for medical school, my career path shifted dramatically because of a chance connection with wildlife. For me, that connection started with the polar bear, a species whose plight has provided some of the defining images associated with climate change, a species whose future we hold in our hands.

As a graduate student, my first field season was spent working out of a remote field camp on the western Hudson Bay, about 15 miles east of Churchill, Manitoba (a.k.a. the Polar Bear Capital of the World). This area, so nicknamed because of the large number of polar bears that congregate there in the fall, was also home to an incredible array of wildlife, including Arctic nesting birds, large herds of caribou, and beluga whales. While polar bears are most numerous and visible during the fall, the bears actually start coming ashore during the summer as the ice on the Bay begins to melt out, and the bears are forced ashore to begin a long fast.

Our field research was primarily done on foot, with miles and miles of walking over the course of the long Arctic summer days, and the possibility of bumping into a polar bear meant that safety measures were taken seriously and practiced regularly. The most basic and important safety measure we had while walking in the field was to scan the horizon with binoculars every few minute, in hopes of spotting any polar bears in the vicinity while they were still a good distance away. On the day I saw my first bear, it was relatively early in the season for polar bears, but the ice had begun to break up on the Bay, a harbinger of polar bears to come. Scan after scan, I saw nothing and continued with my work. And then suddenly, I looked up, and saw a young male bear easily without binoculars, less than 50 feet away. How long had he been following me? Luckily, I was able to make my way safely back to camp. And while it was truly scary to see a bear so close, it was also an event that left an enormous impression on me. It initiated my love of the species and cemented my passion for conserving wildlife and wild places.

Around that same time (the mid-1990s), biologists studying polar bears in the Canadian Arctic documented changes that were occurring within that population of polar bears. These scientists found that reductions in reproductive parameters were correlated with the warming air temperatures that had been documented between 1950 and 1990 and, most importantly, with an increasingly long period where the Hudson Bay was ice free. Because polar bears are completely dependent upon the sea ice for their survival, the directional trend toward less and less ice was of great concern. Twenty years later, I am happy to say that the polar bear is one of the species that I get to study, but saddened to say that the Earth’s CO2 emissions have continued to increase and that the impacts of climate change on polar bears have intensified. No other species better illustrates the impact of climate change on wildlife. Like a real-life version of the game “Break the Ice,” the polar bear’s habitat is disappearing, the ice literally melting at their feet. Their fate is in our hands.

Chinook and Kalluk have been breeding for the past couple of weeks, and we are hopeful, as in years past, that this breeding season will result in the birth of a polar cub in the fall. We will monitor Chinook closely for behavioral and physiological signs of pregnancy and learn as much as we can about the reproductive biology of these amazing animals. Keepers, researchers, and visitors alike have an amazing opportunity to observe our bears in the water and on land at the San Diego Zoo, and in so doing, learn about climate change and the impact that this human-driven change is having on wild polar bears and the Arctic sea ice environment. Polar bears exemplify the role of “conservation ambassadors,” and it is hard to deny the impressive nature of their strength, intelligence, and adaptations to life on the frozen Arctic Ocean.

Climate change may sound like old news to some. Images of polar bears stranded on ice floes were once a common sight in the popular press, but like most news stories, many people have moved on. Unfortunately, climate change has not gone away, and the negative impacts of sea-ice losses on polar bears continue to eke away at their once-pristine Arctic home. I am hopeful that the reemergence of climate change into the news cycle will invigorate people’s interest in doing their part to reverse the trends in CO2 emissions. I am hopeful also that we all seek those connections to nature and wildlife that are so important for engaging us in conservation issues. We can all make a difference.

For those who love our polar bears, and for those who are interested in learning more about how climate change is impacting the species’ Arctic sea ice habitat, I recommend visiting the National Snow and Ice Data Center (NSIDC) website. This page provides daily updates on sea ice conditions in the polar regions, as well as year by year interactive graphics of the dynamic changes in sea ice extent.

Megan Owen is an associate director with the San Diego Zoo Institute for Conservation Research. Read her previous post, Our Panda Conservation Program.

14

Tatqiq: Odd Bear Out

Tatqiq is sure to enjoy Snow Day on Saturday, May 17, 2014!

Tatqiq is sure to enjoy Snow Day on Saturday, May 17, 2014!

Breeding season for polar bears is typically January through June. For Kalluk and Chinook in particular, it can happen anytime in that window. This year, the breeding window began on April 23, 2014, and usually lasts anywhere from 4 to 14 days. In 2013, it occurred in January and only lasted four days. This year, we are seven days into the process and breeding is still happening. However, the frequency has diminished quite a bit from the first few days.

Science still knows very little about polar bear reproduction. What we do know is that polar bears are both induced “ovulators” and delayed “implanters.”

Induced ovulation means that the females don’t have a normal estrus cycle like many mammals do. Male bears follow around females for days or weeks at a time, “wining and dining” them until they are receptive to breeding. Once ovulation is induced, then breeding will commence.

Delayed implantation is tricky because it makes gestation periods and birth dates difficult to predict. Unlike most mammals, after polar bears successfully copulate, they are not immediately pregnant. The fertilized egg remains in a suspended state until conditions are right, at which point the egg implants in the uterus and gestation can begin.

Until late May/early June, Tatqiq is, unfortunately, the odd bear out. Chinook’s hormones are raging, and she is less tolerant of Tatqiq during this time period. Kalluk generally does a good job of breaking up squabbles and moving his sister to a safer spot away from Chinook. If you have been watching the Polar Cam in recent weeks, you have probably noticed Tatqiq seeking refuge in the back corner near the waterfall. This is her safety zone and the spot where she feels she can best defend herself. It is our job as keepers to recognize these changes in behavior and adapt our management strategy. Because of the increased tension between the two females, you will usually only see Kalluk and Chinook on exhibit after 12:30 p.m. When the keepers pull the bears off exhibit for their final meal of the day, we give Tatqiq the polar bear penthouse where she has her own private pool, grass, trees, and air-conditioned bedrooms.

Once breeding season is over, you will again see Kalluk and Tatqiq playing together and there will be less aggression between the two females. Be sure to watch the action daily on Polar Cam!

The Polar Bear Team

34

Spring in Air for Polar Bears

Kalluk digs a pile of snow.

Kalluk digs a pile of snow.

For those of us who live in San Diego, it nearly always feels like spring. (Sorry to those who are experiencing the polar vortex that hit a majority of the country recently!) Despite our consistent temperatures in San Diego, our polar bears follow seasonal changes similar to their wild counterparts in the Arctic.

We recently completed denning season, which normally occurs in the fall months (see Is Chinook Pregnant?). Now we are expecting to start a new cycle: breeding season! Those of you watching our Polar Cam may have noticed three bears on exhibit again. Chinook was reintroduced to Kalluk and Tatqiq after her months of requested seclusion. Chinook was showing some interesting behaviors associated with den making, but we eventually determined that she would not have cubs this time around.

The reintroduction went smoothly, and all the bears acted calmly. At first, Kalluk followed Chinook very closely while she walked around the exhibit. Then they both jumped into the pool for over an hour of play. Eventually, Kalluk was able to separate himself from Chinook, and all the bears rested in their favorite spots in Polar Bear Plunge.

Kalluk has been showing signs that he is getting ready for breeding season, such as an increased interest in sniffing Chinook’s footsteps and urine. However, Chinook is mainly acting coy and disinterested in Kalluk other than play (which certainly could be interpreted as slightly flirtatious behavior). Stay tuned as the saga continues…

Polar Bear Team

43

Is Chinook Pregnant?

Chinook, left, and Kalluk frolicked in the snow a few months ago.

Chinook, left, and Kalluk frolicked in the snow a few months ago.

Around this time of year for the past few years, the number one question we are asked by those familiar with our polar bears is “Is Chinook pregnant?” We nearly always answer with “We sure hope so, but….” Some of you may wonder why we are so elusive with our answer year after year. There are a number of reasons, none of them clandestine. Mainly, the polar bear community is still searching for all the answers. Things are complex in the polar bear world!

Did you know that polar bears have a wide range for gestation, spanning from 164 to 294 days in the wild (195 to 265 days in managed care)? If we determined possible birth on this information alone, this year Chinook could have given birth from July through September, based on when she bred with our male, Kalluk. However, we are aware of research that has studied historic data of births of wild bears and with other observations in the wild. It is hypothesized that date of breeding may not solely determine date of possible birth. Instead, it is a little more complicated than counting days from breeding time. Births generally occur between November and December, with the occasional birth outside those months even when breeding occurs in January, for example (when Kalluk and Chinook bred). Lastly, female polar bears have both induced ovulation and delayed implantation, which makes determining timing and the triggers involved difficult.

We are trying! Through research, we are continuing to learn more and more. Every other day, we collect urine samples from Chinook and fecal samples three times per week, all for hormone analysis. With Chinook’s full cooperation, we perform ultrasound exams weekly once her den is in place. (The den was set up this year at the end of September.) Through research and collaboration, we hope to gain new insights into the complexities of polar bear reproduction and give you more definitive answers in the future to the question, “Is Chinook pregnant?”

The Polar Bear Team, San Diego  Zoo

Watch the bears daily on Polar Cam.

142

Polar Bears: Hormones

Kalluk enjoyed snow day earlier this month.

Kalluk enjoyed snow day earlier this month.

Many Polar Cam viewers have expressed concern about our male polar bear, Kalluk, and his repetitive or restless behaviors. It is hard to see him so driven by his hormones at breeding time if you don’t see his full day. He does eat and rest, but not for the long periods of time as he does when his hormones are not driving him. He is not suffering but just supremely distracted!

The reason we suspect his focus is at the one end of the exhibit is due to the stimulation he may receive there. There is certainly more visual activity with buses and guests stopping to look at him, and the breeze comes right through there, carrying great scent stimuli. Research has shown that there are chemical similarities between many industrial aromas and reproductive hormones. It may well be that Kalluk is constantly testing the breeze in case there is a receptive female polar bear about to come join him. No one really knows how far a polar bear can smell, but no one doubts that their sense of smell is more than anything we could compare.

We know from past testing of his testosterone levels that Kalluk experiences exceptionally high levels for a male polar bear. A recent study indicates that male polar bears’ highest testosterone levels occur from the age of 12 to 18. Kalluk just turned 12, so we may have a tough time for the next few years. We did witness one day of breeding last month on the day after Chinook rejoined Kalluk and Tatqiq; she had been by herself on a pregnancy watch for a few weeks. Their reunion seemed to be more about the excitement of getting together again instead of actual estrus. We fully expect to see another breeding period that lasts anywhere from a few days to a few weeks.

Once Chinook’s hormones indicate that she is ready for breeding, and her behavior indicates she is ready, Kalluk’s attention will turn to only her. Then, as the breeding season wanes, we will get our fun-loving boy back. Polar bear breeding season can last from January to June! Until then, we have increased the amount of fat in his diet, increasing the calories he has to use. We strategically give him enrichment, especially scents, and strategically make beds for him that are in his interest zone.

Rest assured that we are monitoring him closely and responding to whatever he shows might alleviate some of his frustration. Keep watching Chinook as well; she also gives indicators, although much more subtle, of her breeding season!

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

100

Polar Bears: Well, Chinook?

Is she or isn’t she?

*Is she or isn’t she? We still don’t know for sure. Here’s what we do know: Chinook’s fecal hormone profile as of mid-November indicated that pregnancy was still a possibility but birth most likely would be no sooner than January. We have been doing weekly ultrasound exams since October, and the images neither confirm nor deny pregnancy. Polar bears are delayed implanters, so we don’t usually see the uterus unless there is something happening. As of the ultrasound exam this week, our veterinarians are still able to see her uterus. With both these indicators, we are definitely not throwing in the towel.

Chinook’s behavior, though, is picking up. She is playing every day on exhibit and in her back pool. Chinook is also soliciting lots of play time with her keepers. She does, however, go to sleep in her massive bed by noon, again both good and not-so-good signs for pregnancy. The good part: whatever the outcome, our girl is having a very comfortable time keeping us all on pins and needles!

*UPDATE: Chinook has very effectively communicated as of January 1, 2013 that she is NOT pregnant and please very much would like to go play with Tatqiq and that very handsome Kalluk. Today’s ultrasound session also convinced us that we are no longer on pins and needles. So tomorrow all three will be re-united. So uncross those fingers and toes and let them rest until next year!

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