Polar Bear Blog – The Myth of Walking Hibernation

There is no shortage of myths and misconceptions surrounding polar bears and the arctic but possibly the most prevalent are the ideas surrounding walking hibernation. (Actually, I believe that researchers who first coined that word have now backed away from the terms but for now, we’ll stick with walking hibernation.)

So, polar bears have this amazing adaptation in which their metabolic rate slows down after about a week or so without food.  They remain awake during this ‘hibernation’ but their body, essentially, is using less resources and this allows them to withstand prolonged periods of fasting.  In fact, polar bears can survive periods of starvation that would kill most other animals.  An incredible animal.

Most people reading this blog already have a picture of walking hibernation in their mind:  The polar bears trapped on land, slowly wasting away, waiting for the ice… right?  The problem is that this image is just, um, wrong…! It is true that polar bear prefer eating seal, specifically ringed seal.  But which time of year is it most difficult to hunt seals?  July and August right… think again, it is January and February.

The polar bears of western Hudson Bay hit their lowest weights of the year by March, just before seal pupping season.  This is a fact that has been known to researchers and guides for over two decades now, maybe more.  A fact that just seems to get lost in the climate change shuffle.

This is how it works… the bears come off the ice in mid-July.  After seal hunting season (end of March to early July), they are fat and happy; too fat, in fact, they over-heat easily and, as a result, don’t do much at all – we have interpreted this as evidence of ‘walking hibernation’.

But, if you watch bears over the course of the summer season, you see a different story.  As the weather cools and fall approaches, bears become more active.  They forage, possibly on the same levels as grizzlies, spending day after day eating berries, sedges, kelp, you name it.  They patrol the tidal zones looking for sleeping seals, beached whales, anything; starfish with a bear-sized bite out of them are found along the beaches every year.

A study by Markus Dyck suggested that this foraging may maintain their weight and provide, in a sense, a competitive advantage heading out on the ice.  Nick Lunn found that bears feeding at the Churchill garbage dump actually maintained their summer weights and produced more cubs.  Robert Rockwell and Linda Gormezano of the AMNH have irrefutable evidence that snow geese are a major part of the bears’ summer diet.    Here is a great clip about the polar bears’ changing world from the New York Times.

The earliest observations and publications dating back to the 1960s state that polar bears forage in the summer.  Explorers’ and whalers’ journals record polar bears ‘grazing’ in fields, sometimes witnessing up to 80-90 bears foraging together. (And then they killed them but that’s a different blog…). Anyway, you get the picture; summer is actually not really a time of walking hibernation.

Now, let’s get even more complicated… if we can say there is a ‘true’ walking hibernation for polar bears, it occurs once the ice has arrived.  In a sense, the polar bears are gathering in Churchill to head out on the ice and hibernate!  Mind blown!!

When researchers first started collaring polar bears, the bears they were tracking all stopped moving for a week or more.  Researchers believed that the collars had failed when they simply started moving again.  The bears had hunkered down to wait out a blizzard. There is an early ice season window, I believe the first 3-4 weeks where bears successfully hunt seals before the ice gets too thick to do much more than wait at seal breathing holes.  From mid-December until the seal pupping season, life is at its most challenging for a polar bear.  The ice is simply too thick, too packed in.

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The problem we have is that policy makers, activists, lobbyists, politicians, conservation officers, etc etc etc, do not seem to understand that true annual cycle of the polar bear.  The increasing attention and concern shown to these animals has reached the stage where we are harming them instead of helping.  Killing with kindness, if you will.

Current reports indicated that 13 polar bears were in Churchill’s polar bear jail as of this weekend.  There were eight in the jail when I was in town ten days ago and by my calculations, some of these bears have likely spent two or three weeks in confinement.  I do welcome any corrections or clarity that Manitoba Conservation can offer on this matter.

As I understand, one of the bears in jail right now is the Goose Hunter that I watched while in Churchill.  Another is a mother with a single cub, a bear on ‘the fringe’ if you will.  (I am assuming that the policy to move mothers with cubs as soon as possible still exists though.)  Regardless, these bears are being deprived of their natural feeding patterns and being deprived of a critical food source before the winter.  This is a banner year for gooseberries and several other plants.  Every year is a banner year for geese.

Last season, we had an early ‘false’ freezeup, around November 11th, where many bears ‘left’ before the south wind pushed the ice out.  In the final days leading up to freezeup, bears come and go from the ice; they go out and hunt, come back and forage, repeat.   Bears are still trapped and places in the holding compound during this window. Held until final release, around November 22nd last year I believe.  A couple were held much longer, into December.

Is this good or bad – who knows.  Even today, we have no means of tracking the mortality rate of the bears processed by Manitoba Conservation.  But I do know that this early season window may be the difference between life and death for some bears.

The Polar Bear Alert Program is absolutely an essential service and its original intent should be commended.  However, as the world has changed and the bears’ world has changed, their handling policies have not kept up.

After last year’s attack in town, handling outside of town has significantly increased. I feel this is a mistake – Manitoba should be hiring more officers and mobilizing funds for a 24 hour active patrol in the community; make a ‘fortress Churchill’ type of policy to keep the people safe in town for three or four months a year.  To this day, polar bear encounters in town are still reactionary, a response to citizen sightings and calls to the Polar Bear Alert hotline.  This works well but should be part of the a greater picture, not the sole solution.

I don’t believe this is any one person’s fault but instead a case of policy development based incorrect information.  The real question is that how have so many of the world’s polar bear experts and most vocal advocates operated so long under a mistaken understanding of the polar bears’ basic ecology.  Either way, the new policy or interpretation that is resulting in significant handling and confinement of polar bears in Churchill during the summer months must be corrected.  The bears are suffering.

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