Animals site sub feature

Animals site sub feature

8

Baby Gorilla at Home

Imani cradles her infant while on exhibit at the Safari Park.

Imani cradles her infant while on exhibit at the Safari Park.

These past five weeks have been some of the most hectic and rewarding weeks that my fellow keepers and I have experienced on the job! Born via C-section and needing treatment for pneumonia and a collapsed lung, gorilla Imani’s baby girl had a bit of a rough start to life (see video below). Thanks to the dedicated team of people working around the clock, and her own fighting spirit, she eventually pulled through. Since being introduced to her mom and other gorilla troop members at the San Diego Zoo Safari Park, life has been smooth sailing.

Imani has, so far, been the picture of an ideal mother. During the first couple of days of their introduction, Imani experimented with different ways of holding her new baby girl. While raising her “adopted” son Frank, he would often ride on Imani’s back. Gorilla moms usually carry their kids on their back until they reach about three months old. Imani quickly learned that this little newborn would much rather be held close to the chest and would demonstrate the strength of her rehabilitated lungs by crying loudly if Mom tried anything else! Look for Imani out on exhibit carrying the baby, usually in her right arm, while foraging. Having an infant in her arms has not slowed Imani down or diminished her appetite for kale, romaine, sunflower seeds, a tasty piece of acacia browse, you name it!

After Mom has had her fill, one of Imani’s favorite spots to sit down and nurse her baby is the heated pad in the giant root ball at the base of the fallen tree-climbing structure. You can often see Imani resting here at different times throughout the day, baby cradled in her arms. Watch for Imani holding the baby’s hand in her own or grooming her while she nurses. Frank, now 5½ years old, is usually not too far away, and the other gorillas frequently take turns passing by for a peek as they carry on with their own activities.

At the end of the day, the troop returns to the bedroom area for the night. After dinner, Imani usually makes a nest of hay large enough for her, her baby, and five-year-old big brother Frank to sleep together. Come to the Safari Park and watch with us as this little girl grows up!

Jami Pawlowski is a keeper at the San Diego Zoo Safari Park.

25

“Go potty,” Xiao Liwu

What a clever panda boy we have!

What a clever panda boy we have!

Many of you have wondered how we trained the San Diego Zoo’s panda youngster, Xiao Liwu, to provide a urine sample upon request. Teaching a bear to urinate on command takes a lot of patience and observation of the bear and his or her habits. We used a method called capturing a behavior.

We noticed that when “Mr. Wu” shifts off exhibit and goes into the tunnel, which has a concrete floor, he would, fairly regularly, go to the bathroom before he went into his bedroom. Urine is a very important tool for information about any animal to determine health or hormone levels. So, we started keeping a water syringe and extra apples with us when we started shifting him in at night. When we “caught” him going potty, we would say “go potty” and show him the syringe. When he was done, we would offer him his verbal cue, “Good,” and an apple reward.

After about two weeks of this, he started to go potty when we asked him to. We then use the syringe to collect his urine sample off the concrete floor, which is cleaned every day and night. No cup or pan needed!

Jennifer Becerra is a senior keeper at the San Diego Zoo. Read her previous post, Yun Zi Travels to China, Part 2.

8

Orangutans: Why the Burlap?

A young Cinta enjoyed burlap, too!

A young Cinta enjoyed burlap, too!

Satu sits slightly down with a piece of burlap over his head; Indah lies in a hammock completely covered by burlap, and Karen has a burlap bag clutched in her foot as she does somersaults in front of the glass. What’s up with the burlap? Burlap is one of the enrichment items we give the orangutans on exhibit. If you have spent anytime at the San Diego Zoo, you probably have heard of enrichment. Enrichment basically refers to anything given to the animals that will increase their activity both physically and mentally.

When animals are on exhibit, we are limited to items that are natural in appearance, and with orangutans, we are limited further to items that are “orangutan proof.” Orangutans are intelligent, strong, and creative animals. Great care has to be given so that individuals cannot hurt themselves, destroy the items, or, more likely, use the item as a tool for mischief.

In addition to the burlap, pinecones, gourds, bamboo, browse, and palm fronds are enrichment items we commonly use on exhibit. We try to give them items that will encourage natural behaviors. Orangutans are arboreal mammals from the rain forest. They use branches and large fronds to protect themselves from the rain and sun. We give them burlap, browse, and palm fronds to mimic this behavior. We put treats and smears in and on the pinecones, gourds, and bamboo to encourage foraging behaviors and tool use. We have a simulated termite mound in the exhibit, which, of course, does not contain ants or termites but different sauces. It is not so important what is in the termite mound but that they use tools to extract what they want out of it.

Tool use is a learned behavior passed from mother to offspring. We saw Indah actively teaching Cinta to use the termite mound, and it will be great to see her do the same with her newest baby, Aisha. Different groups have different tool use methods, and even individuals have a preference when it comes to extracting the enrichment. When we give bamboo cups with gelatin inside, Satu likes to use his strong jaws and teeth to just break it open, Cinta would pound it on rocks and knock out the gelatin, while Karen uses a small stick to get the good stuff.

You will also notice when you look at the exhibit that there are large, plastic items hung on ropes. While they are not natural looking, they fulfill the other requirement: they are orangutan proof. We use these as permanent enrichment items in the exhibit. In addition to the animals using them to swing and play with, we also put food items inside periodically. As a result, the orangutans check them every day. This increases their activity level, but it also mimics a natural behavior. Orangutans have a mental map of the rain forest: where the fruiting trees are located, and what is edible. They remember where they found food in the past and return to it later.

Tanya Howard is a senior keeper at the San Diego Zoo. Read her previous post, Orangutan Aisha at 5 Months.

14

Orangutan Aisha at 5 Months

What fun to watch Aisha grow!

What fun to watch Aisha grow!

The past five months have gone by so fast! Little orangutan Aisha is growing by leaps and bounds. I forget how small she actually was until I see a picture of her first day outside. Indah continues to be a great mother. She seems even more relaxed with Aisha than she did with Cinta, her first offspring.

The last few weeks have seen an increase in Aisha’s activity level on exhibit. Typically, Indah is active and moving around the exhibit first thing in the morning, and by 11a.m., she finds a comfortable perch in the climbing structure and relaxes for the rest of her time on exhibit, with Aisha hanging on her. Lately, we have seen Aisha off of Mom on the climbing structure and hammocks—it’s so exciting! At first, Indah’s hand was right there, and she was very vigilant. Now, Indah will be a few feet away, sometimes with her back to Aisha, and one time Indah even left the tree and went to the ground for a few minutes! It is amazing to see Aisha on her own, so interested in her surroundings.

Mom and baby are still going inside at 1p.m. so the siamangs can go on exhibit. It will be a while before we are comfortable introducing the baby to the siamangs. Because of male siamang Unkie’s previous behavior with Cinta, we do not want to try this too early, as it could result in unnecessary stress to Indah and Aisha or possibly injury.

When inside, Indah is even more relaxed. At a very young age Indah would put Aisha down in the bedroom and let her explore. It varies greatly between individual mothers when they break that mother-child contact for the first time. Literature has the range as early as 2 months and as late as 18 months. Indah was definitely on the low end of the range! She feels very safe in her bedroom and knows that there is no threat to Aisha inside. In her bedroom, Aisha climbs up the bars and across the ropes and back again. She is very active, but sometimes she just wants to be on Mom. We have a camera system set up in the bedroom, and this has really allowed us to see behaviors between Mom and baby and to see early development that we would not have seen if we were standing there watching. Indah typically is more protective if there are people present and usually will grab Aisha and hold her until people leave the area.

Aisha still does not have any teeth, but she is tasting everything, and everything goes into her mouth. She eats lettuce and would probably eat or try to eat other foods, but Indah is not good with sharing. The majority of Aisha’s nutrition is from nursing.

I get asked a lot how much Aisha weighs. Even though Indah lets Aisha climb and move around, she would never leave Aisha and move to another area without her. We can get weights anytime on Mom and baby together.

It will be great to see Aisha grow and change in the coming months. Every day I am excited to get to work and see all the cute stuff she does. Everything she does is cute!

Tanya Howard is a senior keeper at the San Diego Zoo. Read her previous post, Orangutan Personalities.

43

Elephants Mila and Mary Meet

The San Diego Zoo's newest elephant: Mila.

The San Diego Zoo’s newest elephant: Mila.

Our newest elephant, Mila, is rounding out her first three months with us here at the San Diego Zoo, and she is doing extremely well, exceeding all of our expectations. A few weeks ago she cleared her mandatory quarantine period after receiving a clean bill of health by our veterinarians. As discussed in her previous blog entry, we were awaiting the results from her tuberculosis tests. Mila’s results came back negative, and at her overall health exam, she was in good health.

We have been working very hard to make Mila’s transition to her new home as smooth as possible. One of the most important aspects is that we ask Mila to participate in all of her daily care. Although she has had the chance to meet each member of our elephant care team, we have designated a core group of four keepers to help adjust her to her new life and routine. We use operant conditioning as the focus of our training program, relying heavily on positive reinforcement to reward our elephants. Mila was already conditioned to an array of training before her arrival; however, it has been our goal to get her used to how we work with all of the other elephants at the San Diego Zoo.

We have been working with Mila on having all of her feet hosed and scrubbed with soap, along with presenting her feet for “pedicures.” Other behaviors we have focused on include having her open her mouth for optimal viewing of her teeth, presenting an ear for future blood draws and allowing us to touch every part of her body. This training not only allows us to take care of Mila every day, but it also helps build her trust and confidence with her keepers and her new routine. She continues to amaze us with her ability to learn quickly and adapt to new situations.

Mila explores one of the yards in the Zoo's Elephant Odyssey.

Mila explores one of the yards in the Zoo’s Elephant Odyssey.

As soon as we knew Mila was clear of quarantine, we immediately gave her the opportunity to explore outside of the special needs facility where she had spent all of her time so far at the Zoo. Every elephant who has moved to the Conrad Prebys Elephant Care Center has shown different reactions to moving throughout the facility. Mila, being the confident elephant that she is, had no problem walking through the large entryway and out into the main facility. She was accompanied by one of our keepers who has been working with her since her arrival to help make the exploration more comfortable for her. Mila had plenty of time to explore every inch of the stalls and scale area, becoming familiar with every new sight, smell, and sound.

Her normal care routine was soon transitioned from the special needs facility to the main stalls, which can be viewed by Zoo guests. Every day she was asked to participate in her daily foot care in one of the stalls, given a bath, and even asked to stand on the platform scale so we could record her weight. After a few days, we gave her access to one of the main exhibit yards. The yards are pre-set with plenty of tasty food items in puzzle feeders, along with several novel enrichment items to enhance her experience outside for the first time. Of course, we took every precaution to make sure Mila would be comfortable in the yard; however, she proved ready to explore with enthusiasm, and we couldn’t be happier with her progress into her new home.

Mila is now on exhibit at various times throughout the day for everyone to see and admire. She is not on a schedule, meaning every day is different for her. We try our best to give her as much time as possible out in one of the exhibit yards during the day to allow her to enjoy the sunshine and to get some exercise. She is also now staying in one of the exhibit yards overnight. During her first venture outside overnight, I and another keeper accompanied her to observe her behavior and make sure the experience went well. Her first night went without a hitch, and she continues to spend time in the exhibit overnight as we progress her through acclimating to life at the San Diego Zoo.

It is important to remember that prior to arriving here, Mila had spent the majority of her life without other elephants. It has been more than 30 years since she has interacted with another elephant, and giving her the ability to live in a social setting with other elephants was a key point in moving her here. Since her arrival, Mila has been able to communicate with the rest of the elephants as well as smell, hear, and even see them from a distance. Even though the rest of the female elephants have plenty of experience meeting new arrivals, we were unsure how Mila would react.

Mila flares her ears at Mary.

Mila flares her ears at Mary.

In late January, we gave Mila the first opportunity to meet another elephant with limited interaction. We decided that Mary was the best option, given she is a dominant elephant in the herd, is relatively calm, and has a good track record with meeting newcomers. The first interaction was done with each elephant in separate adjoining yards, using a mesh wall as the barrier between the two elephants. We were uncertain how Mila would react; being excited, nervous, scared, aggressive, or submissive were all possibilities we could have expected to observe. Mary was curious of the newbie, while Mila was surprised to find something as big as her on the other side of the wall! These initial meet-and-greets have the potential to go in many different directions; there is no textbook answer to say how new elephants will react to one another. We use observation and our knowledge of elephant behavior to gauge the success of the introductions.

On day two, we gave Mary and Mila the ability to have increased physical interactions using more exposed barriers between the two of them. Mila started off on the defensive, possibly unsure that Mary, too, is in fact an elephant. It was her initial reaction to let Mary know that Mila was just as big as Mary was. There was nudging and pushing at one another between the barrier, several trunk slaps, and even a temper tantrum or two on Mila’s end. Mila was even flaring her ears out to make herself look more impressive. For the most part, their encounters have been relatively calm and fascinating to watch as the two get to know each other more. It is our hope that Mary’s interactions will help shape Mila’s behavior when she meets other females within our herd. Mary is generally laid back but means business when she needs to.

Elephants are as individual in their personalities as humans are, so each new meeting will come with different behaviors. Only time will tell when we are ready for Mary and Mila to share the same space, but we are confident that their relationship will continue to grow stronger as they spend more time together. In the meantime, look for Mila the next time you visit the Zoo’s Elephant Odyssey—she just may be out on exhibit. The other elephants appreciate your visit to the Zoo as well.

Robbie Clark is a keeper at the San Diego Zoo.

26

Bear Ambassador Learns Importance of Plants

Ambassador Mi Ton Teiow explores some bamboo growing at the San Diego Zoo. This bamboo represents the incredible horticultural collection of San Diego Zoo Global and a key component of giant panda habitat.

Ambassador Mi Ton Teiow explores some bamboo growing at the San Diego Zoo. This bamboo represents the incredible horticultural collection of San Diego Zoo Global and a key component of giant panda habitat.

We’ve mentioned in previous Bear Blog posts that some of the major threats to different bear species are habitat loss, or habitat degradation, or habitat fragmentation. As you can tell, for bear conservation it’s important to consider the amount and quality of bear habitat. For food, bears (except for polar bears) rely on plants. Thus, people concerned about bear conservation often become concerned about the conservation of the plant communities on which the bears depend. Although San Diego Zoo Global is involved in conservation of animals, it also does a lot of work with plants.

Recently I talked to botanists and horticulturists at the San Diego Zoo, and our whimsical Bear Ambassador, Mi Ton Teiow, was able to visit plants from bear habitats around the world. You might know that our horticultural staff grow most of the bamboo eaten by the giant pandas or the eucalyptus eaten by the koalas, but that’s just the beginning of what they do! I knew that certain parts of the Zoo contained plants related to some I’d seen in Andean bear habitat in the cloud forest of southeast Peru, but our horticulturists pointed out close relatives of plants that are important to Andean bears in the dry forest of northwest Peru, as well as plants from Australia, Hawaii, and Africa.

This flowering powder puff tree (Calliandra haematocephala) may catch your eye, but there’s more to the plant collection than what meets the eye.

This flowering powder puff tree (Calliandra haematocephala) may catch your eye, but there’s more to the plant collection than what meets the eye.

One reason they are able to grow such a diversity of plants at the Zoo is its variation in topography, which helps create a wide range of microclimates. I was surprised to learn that during winter, certain parts of the Zoo may receive frost at night! Of course, another reason the horticulture staff is able to grow such diverse plants is their research to understand just what the different plants need to grow and reproduce. Sometimes this research requires them to conduct experiments such as those in the lab to determine the best conditions for propagating orchid seeds, or field trips like those to investigate wild fig trees.

San Diego Zoo Global grows plants for many different reasons, and sometimes because the plants themselves are of conservation concern, plant species can be endangered, and captive reproduction can be an effective tool for plants as well as animals. In addition to plant conservation efforts, horticulture staff grow plants for several reasons related to animal husbandry. As I mentioned earlier, some plants are fed to the animals, providing them with more natural sources of nutrition than they would get otherwise. Parts of other plants are given to animals as a form of enrichment, especially because of their scents. When an animal shreds a few branches it’s been given, the animal is performing a natural behavior in a renewable manner: the horticulture department will grow more!

This diversity of plant species and structure may resemble tropical bear habitat, but it’s actually part of the horticultural collection at the San Diego Zoo.

This diversity of plant species and structure may resemble tropical bear habitat, but it’s actually part of the horticultural collection at the San Diego Zoo.

Woody plants are also used as structures in the animal enclosures. Large limbs, logs, and sometimes stumps are placed so that animals have items to rub on, climb on, and sometimes sleep upon. You can probably see our bears interacting with their log “furniture” any time you visit the Zoo. And, any time you visit, you can pick up a free map and take yourself on a self-guided walking tour of the botanical collection surrounding you. If you’re able to visit the Zoo on the third Friday of a month, you can explore the plant collections further. On those Fridays, called Plant Day & Orchid Odyssey, you can take a free narrated botanical bus tour to learn more about the plant collections, and you can visit the orchid greenhouse, which is home to more than 3,000 orchid plants!

The next time you’re visiting the San Diego Zoo or Safari Park, or a zoo elsewhere, take a closer look at the plants; they’re a whole lot more than “just” landscaping; they’re food, furniture, and enrichment for the animals and plant ambassadors of the habitats on which their wild relatives depend.

Russ Van Horn is a scientist with the San Diego Zoo Institute for Conservation Research. Read his previous post, Bad News Bears.

2

Beware of Crunchy Figs!

Here's a Moreton Bay fig fruit sliced in half.

The fruit of a Ficus sansibarica provides a cozy home for fig wasps.

Recently, the Wildlife Disease Laboratories received an interesting request from Seth Menser, a senior horticulturist at the San Diego Zoo, asking if we could take pictures of plant parts under the microscope. “I would really like to do a couple of shots of a fig cut in half with the fig wasps still inside. I have the figs needed for the shots. And, if you have never seen inside a fig, with the fig wasps, it is a very incredible thing to look at!” We were curious, so agreed to help.

Fig wasp

This amazing view of a fig wasp was taken in our Wildlife Disease Laboratories.

Seth brought up several figs from a Ficus macrophylla, commonly known as a Moreton Bay fig. These trees originate in the subtropical rain forest of eastern Australia but do well in frost-free climates such as ours. These majestic trees can reach up to 200 feet (60 meters) with long, aerial roots providing the tree with additional support to hold up the immense canopy. Seth brought several figs ranging from green and firm to dark maroon with spots on the outside. He explained the life cycle of the fig and the fig wasp as he cut them in half, and we set up the cameras.

Here's one

This female fig wasp has her wings. Is she ready to fly to a new fig?

Ficus trees are unique because the flowering parts of the plants are inside the fruiting parts (figs), making it difficult for insects to pollinate the trees. Thus begins the cooperative relationship with the fig wasp. The fig provides refuge and a food source for the wasps, and, in turn, the wasps pollinate the tree.

To begin the cycle, a tiny female fig wasp enters into a narrow opening (ostiloe) at one end of the fig. While wiggling into this small hole, she often looses a wing or antenna. Safely inside, she lays her eggs. As she is wandering through the fig, she spreads pollen from the fig she hatched in, thus helping the fig tree produce viable seeds. The cycle of the female wasp is complete, and she dies. Her eggs hatch, and the young wasps grow, finding food and refuge in the fig. Interestingly, only female wasps grow wings and leave the fig. The males live their entire life in the fig. Their function is to mate with the females and chew small openings through the fig’s wall for the females to escape, and the cycle begins again.

How many fig wasps can you find in this fig?

How many fig wasps can you find in this fig?

We were totally fascinated by the story. Using a dissecting scope with a camera attachment and a macro lens on a photo stand, we were able to capture the intertwined life cycles of the fig and the wasp. We photographed the narrow ostiole of the immature smooth fig where the female enters. Mature figs looked completely different on the inside. They were soft and fleshy, with delicate flower structures and seeds lightly attached to the inner walls. Each mature fig contained several wingless male wasps, and Seth was lucky enough to find one female flighted wasp.

At first glance, theses tiny wasps are difficult to see. The magnification helps, but a keen eye is needed to see them. How many can you find?

April Gorow is a senior pathology technician with the San Diego Zoo Institute for Conservation Research. Read her previous post, We Never Stop Learning.

0

Pelican Keeper Chat

The great white pelican is an impressive bird!

The great white pelican is an impressive bird!

If you have recently visited the San Diego Zoo, you probably noticed four new additions to the African Marsh exhibit across from Eagle Trail. These new birds may be young (a little over one year old), but they are hard to overlook. Often eliciting surprised gasps from visitors when seen up close, these bold birds quickly make a grand impression. Yes, the two male and two female great white pelicans Pelecanus onocrotalus are the source of many visitors’ questions. To find answers to some of those questions, I sought out Amelia Suarez, one of their keepers, and had a chat with her about those prodigious pelicans.



Whose idea was it to get pelicans for the African Marsh exhibit?

During a conversation I had with our bird curator, I asked if we could get a few pelicans for the Zoo’s African Marsh exhibit. I love pelicans! When I used to go to La Jolla Cove, I would see the cormorants and pelicans living next to each other. And while the cormorants and pelicans we have in southern California are not the same species as the ones we have at the Zoo, I thought they would go nicely together.

Do the pelicans have different personalities?
Definitely! They are all young, so they frequently act like curious kids and play with anything new. Three of the pelicans are hand raised, but one of the females was raised by her parents. She came to the Zoo very shy and didn’t want to come close to me during feeding sessions. She has since gotten over most of her cautious behavior and now politely takes food from my hand. She even vocalizes to me to let me know she wants her fish.

What preparations did you do before they came to the Zoo?
The biggest thing we did was to add some palm stumps to the exhibit for them to perch on. Most of the work we did was after they were introduced. We cut some vegetation back to make space for them to hang out. And they were so curious about visitors that we put up a perimeter fence and added a number of plants to keep them from getting too close to our guests.

What did the birds in the African Marsh think of their new flock-mates?
The saddle-billed storks weren’t thrilled with them initially. They had a long-established territory, and they didn’t want other large birds to push them around. There were a couple of mild spats between the two species, but the storks have since calmed down quite a bit, and they usually slowly move to another part of the exhibit when the pelicans are on the move.

The cormorants, on the other hand, tolerate them unless the pelicans get too close to the tree where they have their nests, and then the cormorants get agitated and—in unison—bark and warn the pelicans off.

Is feeding in that exhibit any different now?
For their size, they don’t eat much—just one or two large trout per feeding. (Note: depending on the time of year there are two or three feedings per day.) It just means a few extra fish in the bucket. Oh, and of course they want to be the first ones to eat, so the cormorants and storks have to wait their turn!

Do you have a favorite among the pelicans?
All four are my favorite! The males like to pick up fish and fling them halfway across the exhibit. They also help me clean by biting the handle of the rake or brush while I’m using it. The females are sweet; one runs up and leans on me when I enter the exhibit.

Do you have hopes to breed these birds?
We do hope that they will breed once they are sexually mature. I can see the parent-raised female being a good mom if she can attract the attention of one of the males.

What is one thing people would be interested to know about the pelicans that they may not know just by looking at them for a few minutes?
How big they are! I know that anyone can easily see that they are big birds, but when I’m standing next to one of the males, and he is flapping his wings, I realize how truly huge these birds are! (Note: A great white pelican’s wingspan can be over 9 feet!)

Mike Grue is a senior keeper at the San Diego Zoo. Read his previous post, Australian Bird Keeper Chat.

116

Pumpkin Fun for Elephants

Emanti prepares to dunk his pumpkin.

Emanti prepares to dunk his pumpkin.

As the days grow shorter, the nights grow longer, it is finally harvest time! Pumpkins are carved out and are available for elephant enrichment. The keepers decided to give the elephants a pumpkin party in the afternoon yesterday, October 30, 2013. Pumpkins were placed in the East Yard; some are empty but others are stuffed with alfalfa pellets. Also, there were frozen juice pops and alfalfa flakes hidden everywhere!

How about a pumpkin toss, Kami?

How about a pumpkin toss, Kami?

Umngani found her pumpkins right away with Inhlonipho following close behind her. Msholo loves pumpkins, so he smashed and ate his pretty quickly. A couple of them rolled into the pool, and he went right in to eat them in the water. Emanti kicked one around, but he was only interested in the pellets inside.

Little Qinisa was running around trying to keep track of everybody, but in the end, she ran down to join her mom, Swazi, in eating a pumpkin that had rolled down near the pool. The other members of the herd went off on their separate ways to find frozen pops and alfalfa. In the end, all had their fair share of fun, including us keepers!

Laura Price is a keeper at the San Diego Zoo Safari Park. Read her previous post, 7th Birthday for Khosi.

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.