International Polar Bear Day on Feb 27th

By Elizabeth Trickey

Polar bears – beautiful to view and so interesting to learn about.  That’s why I travelled up to Churchill, Manitoba, the polar bear capital of the world, to spend some time watching these amazing creatures.  I spent several days and nights on the shores of Hudson Bay – the nights spent in a trailer (similar to a rail car with bunk beds, a dining room and a lounge) and during the day, travelling about the Arctic plain in a Tundra Buggy.  The buggy was like a wide bus with huge tires and an outdoor viewing platform. 

Our buggy driver was wonderful, providing lots of information for the passengers.  I took this tour at the height of polar bear season and was surprised at how few bears I actually saw over the 3 days I was out looking.  October and November are the months when they are most abundant around Churchill, since this is the time of year when polar bears migrate through the area, waiting for the bay to freeze over.    

Polar bears are the only bear species to be considered marine animals.  They can swim for days at a time as they move between ice floes.  Even though they only use their front paws to swim, they can reach speeds up to 10km/h.  

The first thing I should mention is that there are 19 sub-populations of polar bears in the Arctic and this article primarily discusses the one in Western Hudson Bay.  These polar bears have a migration pattern that starts around the Churchill area.  When winter approaches and the waters of Hudson Bay begin to freeze up, the polar bears climb aboard the newly frozen ice to go seal hunting, ringed seals being their main food source.  The bears travel over the frozen ice, out to where the ice is fractured.  This is because the seals they are hunting need a place to get out of the water, which is where the bears often lie in wait for them.    

Ice may be solid and appear non-moving, but the water underneath is not, and as the current moves, so does the ice.  The polar bears spend the next 7-8 months feeding on seals as the ice floes drift away from the Churchill area.  As the warmer spring weather arrives, the ice melts and the bears make their way back to the land.  However, due to the drifting ice, they end up much further south.  The polar bears gradually make their way back to Churchill by land to wait for the next freeze-up.  During this land migration, they eat very little, so it important that they build up stores of fat during the seal hunt to get them through to the next hunt. 

 

 

As with most things, there are exceptions.  This annual routine does not happen with female polar bears that are pregnant.  Mating occurs in the winter when the bears are out on the ice, feeding on seals.  The egg implantation does not occur until the following autumn, and only if the mother bear is healthy enough.  At this point, the mother has not eaten for months and will not eat again until after the cubs are born and old enough to venture outside of their den, which is usually early spring.  That means that the mother may not eat for up to 8 months.  Wow!  Now that’s dedication to her cubs! 

During the autumn, after the land migration back to the Churchill area, the pregnant polar bears make very small dens out of peat and snow.  They do not join the other bears that return to the ice.  Mothers give birth to 1-4 cubs (usually just 2) in the winter.  A COY (cub of the year) stays with its mother for about 2 years. It is very tiny at birth, less than 1½ pounds, with very little fur, but the cub grows fast.  By 3 months old, it is about 25 pounds.  Mother’s milk has a very high fat content that helps the cub grow quickly.  It nurses for 1 or 2 years depending on the health of the mother, since nursing takes a lot of energy. 

In those first 2 years with Momma Bear, the cub is taught all that is needed to survive in the harsh winter environment, such as migration, dealing with potential dangers, and hunting for seals.  Oh, and staying away from Papa Bear.  Male polar bears will sometimes try to kill the cubs or even the mother.  A few reasons have been suggested as to why this happens including because the male wants to mate, he’s hungry, or just because he can.  Scientists do not know for sure.  After that 2 year period of learning, the cub lives on its own and is considered “sub-adult” until it is about 5 years old.  Polar bear cub pictures by U.S. Fish and Wildlife Service

 

 

 

Polar bears facts:

• solitary animals 
• live for 25-30 years in the wild and up to 35 years in captivity 
• females reach reproductive maturity at about 5 years old and tend to have a litter every 3 years
• 22 000 – 31 000 polar bears worldwide 
• 60% of all polar bears live in Canada 
• males can weigh up to 1700 lbs and are 6-10 feet long 
• have 3 eyelids (an extra lid to protect from the icy weather) 
• fur is translucent though looks white, but their skin is black 
• have blue tongues 
• can smell prey up to a kilometer away 
• no natural predators and no fear of humans 
• can run 40km/h

Not all polar bears sit quietly by the bay, waiting for the freeze-up.  They will occasionally hunt for terrestrial food such as birds, rabbits and foxes.  After all, they haven’t eaten much in 4 months!  Interestingly, the bears have an inherent ability to judge the energy they will expend in chasing an animal vs. the energy they will get by eating it.  These bears seem to know that unless they can catch the prey quickly, it isn’t worth the effort.  So mostly, polar bears are just couch potatoes (tundra biscuits?) just lazing around, until it’s time to go hunting for seals.   

What Churchill polar bears have learned is that not all potential food moves quickly, and sometimes it doesn’t move at all.  Bears have been known to leave the coastline and stroll into the town looking for food.  They might find delicious treats in garbage or food storage sheds.  Or meet up with an unlucky resident out walking the dog!  For this reason, there is a city by-law in Churchill that says you must keep your car doors unlocked in case somebody needs to take shelter quickly!  I kid you not.  OK, how many of you who are reading this are already googling that?   

Churchill is a very small town with less than 900 people.  They have learned to live around the bears as safely as possible by adjusting their lifestyles.  Signs around town say “Don’t walk, get a ride” or “Look before exiting building”.  They have an amazing recreation centre that has everything you could ever want – hockey and curling rinks, swimming pool, gyms, a library, health centre, high school, playground, and even a theatre!  All in one big complex where the bears aren’t allowed!  Hallowe’en, which occurs at the height of polar bear season, is a major event that involves the entire town making sure the children are safe as they enjoy their special night.  It is good to know that some humans are respecting wildlife and learning to live peacefully alongside them.   

But we all know that things don’t always work according to the plan.  That’s why there is jail.  Yes, Churchill has a jail for those that don’t heed warnings.  For the polar bears, that is!  When bears come into town, despite being redirected back to the coast, they are put in jail for a minimum of 30 days.  And they stay at the ‘crowbar hotel’ until the bay freezes over.  It is then that they get pardoned and released about 40 miles north of Churchill where they can continue their migration onto the ice and away from the town. 

 

Most of us know that different species can mate, making a hybrid.  Like the wolf and coyote – we now have coywolves; horses and donkeys beget mules; and a cauliflower and broccoli produce a broccoflower!  Well, did you know that polar bears have mated with grizzly bears?  They are called either “grolars” or “pizzlies”!  It is often the polar bear that is the female of this match, and because it is the mother who raises the cubs, these hybrids are raised as polar bears.  This is a very rare occurrence since the 2 species of bear don’t tend to share the same habitat.  I’ll bet some of you are googling that fact, too!  

 

 

 

 

 

 

 

 

Polar bears are an important part of our world.  They are considered a “keystone” species, which means they have a critical role in their ecosystem, being the predator at the top.  Polar bears keep their habitat in balance and their own health has a direct impact on all other life in their environment.    

For thousands of years, polar bears have also provided a living for people living in northern communities who have hunted them for food and material resources such as clothing, tools and bedding.  For areas like Churchill that are home to polar bears, the bears provide tourism dollars to those communities.   

As global warming melts the sea ice, these polar bears have less time to feed on seals.  As mentioned earlier, they are marine animals so they need the ice to survive.  The only reason they are on land is to make their way back to the northern ice where they can begin feeding again.  As it is, the bears go without food for several months during the summer while they migrate back north.  Less time on the ice means less time to eat.  This is an issue for all polar bears, especially the pregnant ones.  And that equates to fewer cubs being born, and those that are born are at risk of malnutrition.  

Being on land for much longer periods, hungry polar bears will start looking for other food sources.  This includes the greater possibility of human conflict in coastal communities where bears go looking for food while waiting for the ice to freeze.  The bears may also begin finding other animals or vegetation to eat.  Because our natural world is a balance, this would upset that balance and create shortages of food for other species. 

The loss of sea ice also contributes to habitat destruction since the open water allows for more shipping through the polar bear habitat.  As well, industries have begun looking to the Arctic for oil and gas sources.  The polar bear ecosystem will be put in danger with the threat of oil spills and poisoning due to the use of toxic chemicals, not just for themselves, but also for their prey.    

There is much controversy about the polar bear population in Canada.  Some studies will say that more bears are being counted so they are increasing in number.  Well, yes, more bears will be counted because they are on land for a significantly longer period of time and they are more visible on land than when they blend into the ice.  Northern communities are saying that they are experiencing more bears coming into their towns.  Does that mean there are more bears overall or that the bears aren’t getting enough seals, so they are looking for other food sources in towns?  What is the most telling about the polar bear population is that fewer cubs are being born.   

It is difficult to say how all polar bear populations are faring since their habitats cover the entire Arctic, in areas so remote that it is impossible to study.  Some of these regions are extremely cold so melting ice may not be an issue.  In colder areas such as Greenland, there is less ice loss, and polar bear numbers appear to be steady.  

Depending on the country where polar bears are found, their status is anywhere from “Special Concern” to “Threatened”.  In the next 30 years, the number of polar bears in Canada is expected to drop by a third.  Although it is thought that the bears could gradually adapt to a warmer climate, they cannot adapt quickly enough in the face of human induced global warming.  The polar bears need the sea ice, which is their habitat, in order to survive.   

Although industry is a major cause of global warming, all activities that generate heat will contribute to this problem.  People use furnaces in the winter and air conditioners in the summer, both of which generate heat through use.  Just get close to the exhaust pipe on your car after driving somewhere to see how much heat is being put into the atmosphere.  Lots of things in our homes give off heat – TVs, computers, hair dryers, stoves, lights, hot water tanks, and dishwashers. 

We can all do our part in reducing global warming.  On February 27th help the polar bears by finding ways to reduce your carbon output throughout the year.  Put on a sweater and turn down your thermostat.  Leave the car at home and walk or bike to the store and work.  Make sure your house is energy efficient.  Let’s all be a part of the solution.

Churchill polar bear photos below courtesy of the author Elizabeth Trickey.