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10 Festive Reindeer Facts

‘Tis the season to be jolly! What could be more merry than Santa’s sleigh? Well, without his dexterous reindeer, Old Saint Nick’s mode of transportation would not get very far. So today, we would like to share a few fun facts about this festive species.

Wild & Fun: 10 Festive Facts About Reindeer

1. Reindeer or caribou?
In Europe, they’re known as reindeer. In North America, the term reindeer is used for Eurasian populations, while the name caribou refers to wild populations found in the country. However, both reindeer and caribou are classified as the same genus and species, rangifer tarandus. So for the purpose of simplicity and sticking with the holiday theme, we’ll call them reindeer for the rest of this blog.

Wild & Fun: 10 Festive Facts About Reindeer

2. Males AND females grow antlers.
Male antlers may grow twice as long as their female counterparts; still, reindeer are the only deer species to practice gender equality when it comes to their most memorable characteristic. Males begin to grow antlers in February and females start in May. Both stop growing around the same time, but a male’s antlers typically drop off in November, while a female’s remain through winter until their calves are born in spring. If you’re following this logic, our good pal Rudolph the red-nosed reindeer was most likely a female, because she was rocking her antlers on Christmas Eve.

Wild & Fun: 10 Festive Facts About Reindeer

3. Hard antlers start out soft and fuzzy.
Since antlers fall off and grow back every year, a reindeer is said to be in “velvet” while the new pair of antlers grow. After the velvet dries up, the reindeer unveils its hard antler cores by rubbing its deciduous horns against a rock or tree. Ta-da!

Wild & Fun: 10 Festive Facts About Reindeer

4. Reindeer calves are quick learners.
Newborns are able to stand one hour after birth, and they can outrun humans when they reach one day old. Calves are also weaned from their mothers as early as one to six months of age.

Wild & Fun: 10 Festive Facts About Reindeer

5. They have hairy feet.
Reindeer are built for subzero temps, so they’re covered in hair from their nose to the bottom of their feet. The hair on their hooves provides an excellent grip when trekking over frozen landscapes. Thus, the hairy hooves of reindeer have adapted into snowshoes for these Arctic animals.

Wild & Fun: 10 Festive Facts About Reindeer

6. Reindeer hooves are anatomically noisy.
“Up On The Housetop” and other holiday jingles often imply that the “click, click, click” we hear upon Santa’s arrival is the result of his herd’s stampeding feet. In fact, many hoofed animals make loud noises when their feet meet hard surfaces, but not reindeer. The metallic sound of reindeer hooves is actually due to tendons slipping over their foot bones as they walk.

Wild & Fun: 10 Festive Facts About Reindeer

7. They love crowds…
… of other reindeer, of course. Since they are social animals, reindeer live in herds of 10 to several hundred. So Santa was somewhat limiting his holiday herd by having only nine reindeer. Imagine the horsepower his sleigh would have if his herd included 100 fancifully named members!

Wild & Fun: 10 Festive Facts About Reindeer

8. Reindeer are good swimmers.
Santa’s exclusive herd might be capable of flying, but the rest of the species is not. However, since reindeer migrate to follow their food supply and avoid harsh conditions, chances are they come into contact with water. Luckily, reindeer use their wide, two-toed hooves like paddles that push water and allow these mammals to swim from four to six miles per hour.

Wild & Fun: 10 Festive Facts About Reindeer

9. Their eyes change color in winter.
To adapt to the varying levels of light in their northern habitat, part of a reindeer’s eye changes color and increases their vision sensitivity. The layer of tissue behind the retina that reflects light (tapetum lucidum) turns blue during winter and allows reindeer to see slightly more of their surroundings, even if what they can see is not that sharp or in focus. This seasonal trade-off has its advantages, especially if it improves a reindeer’s ability to spot predators.

Wild & Fun: 10 Festive Facts About Reindeer

10. Like humans, reindeer “wear” layers.
A reindeer has two coat layers: the undercoat is made of soft, fine wool that grows next to the skin, and the top layer consists of long, hollow guard hairs. Similar to a hollow-fill winter jacket worn by humans, the stiff top layer insulates the animal and keeps it warm against the wind and cold. These hollow hairs also help reindeer float. In other words, reindeer have incredible fashion sense.

Do you have any reindeer facts to add to this list? Share your thoughts in the comments.

 

Jenn Beening is the social media specialist for San Diego Zoo Global. Read her previous post, What We’re Thankful For.

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Polar Bears: Breeding Season!

Kalluk and the rest of us eagerly await a polar bear cub or two!

We are all on pins and needles to see if the San Diego Zoo’s polar bears, Kalluk and Chinook, will breed this year. They have always been early birds by breeding in March and even as early as February! But normal breeding time for polar bears is April through May and sometimes as late as June, something we won’t even contemplate! From the looks of how flirtatious Chinook has been and how attentive Kalluk seems, our patience should be rewarded.

We are still participating in reproductive studies looking at hormones excreted in the bears’ urine and feces, but for the most part we still rely on behavior observations. One of the very interesting behaviors we see is with Chinook. Typically, a week before actual breeding and continuing right up to actual, we see her have seizure-like spasms followed by weakness in her back legs. The spasms last only seconds and the weakness only a few minutes. If you don’t know what these are, they can be very scary to see!

But there is no need to worry: Chinook is not alone with these. Most of the other breeding female polar bears show the same behavior. I have asked polar bear biologists who have spent many years observing bears in the Arctic and have sent them video of the process, and they are mystified as to its purpose. Perhaps it plays some role in preparing a female’s legs to hold the male during breeding, since males are usually twice the size, and she may bear his weight for long moments. In the last week we have seen Chinook have these spasms, and over the last few days they have increased both in frequency and intensity. This should be a sign that we are almost there!

We all know what follows: waiting to see if Chinook becomes pregnant and gives birth. I have been getting lots of experience working with polar bear cubs over the last few years since Kalluk and Tatqiq joined us as cubs in 2001. I have just returned from a second visit with Siku, the polar bear cub born at the Scandinavian Wildlife Park in Denmark. My first visit was to share what we learned in preparing our polar bear youngsters for life in San Diego. Siku still was not yet walking then and was not quite 13 weeks old. On my recent trip, Siku was now 21 weeks and was walking, running, swimming, and being overall an adorable monster!

Since Siku’s mom did not produce milk, the decision was made to hand raise him, which meant having close contact with him (not a problem when his fastest speed was a quick crawl!). He is now rambunctious and, as polar bears need to do, he is jumping, grabbing, and mouthing everything and everyone in sight. Mom polar bears are well equipped to handle this; human caregivers, not so much!

This trip was to help the team in Denmark move ahead with management that increases Siku’s independence and encourages his natural instincts as a polar bear. He did extremely well with every challenge of independence. You can imagine how difficult it is, though, for the team who has been caring for him all these months to see that maybe he didn’t need them as much anymore, or at least not in the same ways. I must say how proud I was to assure them and show them the close ties we have with our three polar bears and how much that strengthens when you’re not worried about when the next play jump comes from a now 60-pound and often wet white ball of teeth and claws! All meant in fun, but still dangerous for fragile humans!

Siku has lots of toys to encourage his natural learning behavior and is getting plenty of opportunities to learn with his training sessions. At 21 weeks, he has already learned several important behaviors from his keepers such as “sit,” “stand,” “down,” “shift,” “come,” and how to sit on a scale.

In choosing his name, thought was given to the chance to represent wild polar bears and the people who share the Arctic. Siku is from the Inuit language for sea ice. Siku will remind everyone that we are losing our arctic ice due to warming trends in our climate.  Science has proven this warming is caused by the increase of carbon emissions in our atmosphere. Siku and our three polar bears, Chinook, Kalluk, and Tatqiq, are ambassadors who remind all of us of their wild cousins and that we must make changes to help save their arctic home.

As you enjoy watching and hearing about these great ice bears, please keep in mind everything you can do to help. Then do it!

JoAnne Simerson is a senior keeper at the San Diego Zoo. Read her previous post, Polar Bears: Back to 3.

UPDATE: Two days after this was written, Kalluk and Chinook began breeding. November 2 is the first possible day of birth if Chinook is pregnant! The waiting begins. . .

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More Arctic Ambassador Adventures

Hali attended Keeper Leadership Camp, sponsored by Polar Bears International, in Churchill, Manitoba, Canada. Read her previous post, Eye to Eye with Wild Polar Bears.

After spending what we thought was an unstoppable day on the tundra viewing a mother polar bear and her two cubs, the next day proved us wrong. This time we again saw a polar bear off in the distance of our lodge early in the morning. This bear had no interest in coming any closer, which was perfectly fine with us. Taking in the beautiful colors of the sunrise as we headed out on the Tundra Buggy for the day was enough. However, we were in for quite a surprise!

A bit into our trip, we encountered our mother polar bear and her cubs, so we decided to stop for awhile and see what would happen. Another Tundra Buggy with guests had also stopped, and the bear family had some interest in them. We watched in amazement as the bears slowly inched their way toward them, seemingly headed by one brave cub. The mama was relaxed and allowed her baby to approach the buggy, sniff the tires, stand up to get a better look at the people, and then go back to Mom and sibling to roll around in the scrub brush. A little time later, we got our turn! This time, both cubs decided we were interesting enough to explore and came over to us. NOTHING can describe how I felt looking into a young polar bear cub’s eyes: dark pools of curiosity, completely unaware of the human impact on his simple, yet complex environment. Soon after, mama bear settled down and nursed her two cubs with all of us watching in amazement. The tenderness she exhibited as she caressed her two children was very human-like, and again the tears came a-pouring!

Polar bears are dependent upon sea ice to survive. This specialized apex predator of the Arctic hunts ringed seals and bearded seals by waiting at seal breathing holes from their icy platform. No other food provides the necessary fat needed for polar bears to survive the harsh climate. The bears that live on Hudson Bay in Manitoba, Canada, are certainly no exception. Because of the currents and fresh water from the many rivers decreasing the salinity of the Hudson Bay, the ice there freezes earliest in the winter and melts the latest in the summer, making it an acceptable environment for the bears to come this far south. During this time when the ice has melted, the bears seek land, where they fast for the months until the ice forms again.

The bears of Hudson Bay are adapted to this normal fasting period of two to three months (six months for a denning female) and live off of the fat they accumulated while living on the sea ice during the winter. However, since the Industrial Revolution, humans have been steadily increasing the amount of carbon released into the atmosphere, which is warming the Earth and this is causing the ice to melt sooner and refreeze later. Since the late 1980s, the polar bears of Hudson Bay have experienced a one-week decrease in the presence of their sea ice per decade; this amounts to a 22 percent decrease in the ice and also a 22 percent decrease in the polar bear population. And the ice that is freezing each winter is getting smaller. As the water temperature rises, the ice will eventually not refreeze at all in the Hudson Bay, and that will mean no more polar bears there.

Over 90 percent of today’s scientists agree that the increase in global warming is human caused. A certain amount of greenhouse gases are natural and are necessary to keep our planet warm; it’s just that when you exceed the amount that our atmosphere can release naturally, they get trapped and cause all the trouble. The fundamental laws of physics state that the release of carbon into the atmosphere is causing our planet to warm up. As we warm, the ice melts in the Arctic, causing polar bears to lose their hunting ground. While on land, the bears lose an average of 2.2 pounds (1 kilogram) a day, so the longer the bears have to wait to eat, the thinner they become.

Female polar bears of good condition weigh between 440 and 660 pounds (200 and 300 kilograms). A bear that has successfully mated will not produce cubs if her body condition isn’t capable of handling another bout of fasting as she enters a den to have her young. Since polar bears experience delayed implantation, her body will reabsorb the fertilized egg if she isn’t physically able to bring the cubs to maturation. Scientists have concluded that a female bear must weigh at least 400 pounds (180 kilograms) in order to produce cubs. Doing the math, one can see that waiting longer and longer to eat will decrease cub births and expedite a population decrease.

The lives of polar bears and the survival of the arctic ecosystem is in our hands. This video on the Polar Bears International website shows the decrease in the sea ice in lapsed time. Look at the dates on the upper-right corner of the video to see the years. There were about 1,200 bears living in the Hudson Bay area in 1984, and the last count in 2004 was 935 bears.

No one can predict when the sea ice will be gone for good on the Hudson Bay, but scientists do agree that it will continue to melt if we don’t stop it. As daunting as that thought is, scientists also agree that this can be stopped, and there is great reason to hope if we act NOW! The carbon emissions that our planet can safely handle are 350 PPM (parts per million). We are currently at 380 PPM and steadily climbing. To get this number down to 350, we need to change our lifestyles and all work together toward carbon reduction. There are so many great things we can all do to help the situation, and I plan to address some of them in my next blog post, so please check back. The polar bears are counting on us!

Hali O’Connor is a senior keeper at the San Diego Zoo. You can also read blog posts from the other keepers attending Keeper Leadership Camp.