By Nat Hab Expedition Leader Katrina Rosen
Originally, polar bears were believed to be one large family that interacted with one another and aimlessly wandered atop the world. However, the notion that setting off in an unknown direction will lead to food, mates and shelter is either credulous or evidence of remarkable bravery, as demonstrated by early Arctic explorers.
Some polar bears never step onto land, living their entire lives on the ice. They are as marine as belugas or sea lions, truly embodying their name, Ursus Maritimus. Yet, here we are, near the southernmost range of the polar bears. The bay is unfrozen, and this carnivorous maritime animal roams the land.
You might wonder, “Why don’t they go further north?” The reality is that home is where the heart is. These large nomads lead lives of fidelity.
Most of us love to travel—heading south or skiing in the winter, staying by a lake in the summer. Traveling is a shared passion, but ultimately, we always return home. It’s familiar, comfortable and a place where we have shelter, food and friends.
The same is true for all polar bears.
While Hudson Bay is frozen, the polar bears from the east and west may intermix, but once the spring break-up arrives, they remain incredibly faithful to their summer home ranges. As the last ice melts in the southeast corner of the bay, our western polar bears gradually make their way toward Churchill. This large predator knows this is where the ice will form again first. The pregnant females know they will find safe denning areas within sixty miles of the sea. They know this from their upbringing. Fortunately for us, this congregation of bears is within sight of a relatively modern town.
Canada may house 60% of the polar bear population, but the most special ones are just miles from our Polar Rover. We are in the midst of the Western Hudson Bay subpopulation, numbering around 850. These are the world’s most famous polar bears. As we traverse the tundra, consider this as Hollywood Boulevard, Manitoba—our bears are the stars.
Not just because they are as adorable as Channing Tatum, but this Western Hudson Bay population has contributed significantly to our understanding of polar bear biology and ecology more than any other subpopulation. The reason is simple—studying bears here is less expensive than in remote, higher latitudes, especially those contrasting with the summer terrain.
One of the first tasks of the biologists was to develop safe techniques for capturing and tagging individual bears. They were marked with ear tags and personalized identification tattoos on their inner lips. Through this method and the recapturing of the same bears in subsequent years, along with returned tags from Inuit hunters, they demonstrated the polar bears’ seasonal fidelity.
Shores of Hudson Bay, photographed by Nat Hab Expedition Leader © Eddy Savage
Regardless of the distances they traveled to find seals in the winter, they always returned to the Manitoba coast in summer. From this data, biologists identified nineteen subpopulations of polar bears, each living within their ranges. This knowledge enabled the development of appropriate management and conservation strategies for each area.
Let me paint a picture, for little has changed since the 1970s. Just north of Churchill, a predominantly flat esker remains from the last major glaciation. Beyond it, a barren land of rolling rock, arctic plants, and permafrost extends into the shallow tidal flats of Hudson Bay. The Churchill River empties to the west of a pointed headland and the east of a prominent spit. It’s a bleak, windy place with no geographical relief or cover. Here, in 1976, an observation tower was built to study the polar bears arriving in large numbers every fall.
The researchers observed subadult males sparing and subadult females steering clear of interactions. Mostly, they found that the bears were relatively inactive. During autumn, when the bay is devoid of ice, polar bears eat very little, metabolizing stored energy reserves slowly until they return to the ice.
Once radio collars were developed, they fit well only on females, as the males’ necks were larger than their heads. The collars showed a range variance between 1,150 and 94,000 square miles, proving that the polar bears returned to the same area. Researchers could now track how far pregnant females moved inland, study the unique peat moss dens, and begin to unravel the concentration of dens near here, a topic we will delve into later.
The dates of the bay’s ice breakup and refreeze, recorded by researchers, provided valuable evidence in later years of the detrimental effects early ice disappearance has on polar bears.
Also, in 1976, the Churchill Northern Study Center was founded. Still operational year-round today, it supports scientific research, contributing significantly to our knowledge of polar bears.
Recently, advancements have allowed male polar bears to be tracked using battery-operated ear tags. On the Polar Bears International website, we can watch live tracking of polar bears every winter while they are on the ice.
The seasonal movement of our Western Hudson Bay bears brought the understanding that was craved. By placing themselves in the right location, the bears came to the scientists. A question that remains mystifying and is still under research is: How exactly do polar bears navigate?
When I was 13, I was lost overnight in the forest. I never expected to be so far away, but I knew I would eventually find my way back home. When the sun rose, I kept it on my left shoulder and trekked out for hours in the same direction.
Polar bears are incredibly intelligent. Whether they navigate by the sun, stars, prevailing winds, or their sense of smell, which is far superior to our understanding, they know where they want to go—back to the area where they were born and raised by their mothers.
If nothing else, this place is the polar bear scientific research capital of the world because home is where the heart is.
