
Largest Land Predator
Largest Land Predator
The world's largest land predators, polar bears spend the winter hunting and eating seals -- they can eat up to three hundred pounds of meat in a single sitting. It's not surprising, then, that adult males typically range in weight from 775 to more than 1,500 pounds; females are considerably smaller, normally weighing in at 330 to 550 pounds.

Bear Jail
Bear Jail
When bears get too close to the town of Churchill, they're tranquilized and deposited in Manitoba Conservation's bear holding facility, or "bear jail," which holds up to 22 bears at a time. The bears are treated for infections, vital statistics are taken and recorded, and the bears are tagged for future identification. Their stay is not permanent, however; at regular intervals, the bears are flown north, by helicopter, where they can roam the ice and hunt seals.

Tundra Buggy
Tundra Buggy
The town of Churchill depends heavily on tourism, for as many as 10,000 visitors will come in a given season to see polar bears up close. These so-called tundra buggies, which are modified buses that have been re-mounted onto giant tractor tires, allow visitors to get close to the bears but still stay safely out of harm's way.

Fur and Blubber
Fur and Blubber
Despite appearances to the contrary, a polar bear's fur is not white. Each hair shaft is transparent, pigment-free, and exhibits a hollow core. Indeed, polar bears only look white because the hollow core scatters and reflects light, much like ice and snow does. Also surprising is the fact that a polar bear's skin is actually black. The hollow shafts of fur draw the sun's rays in toward the skin to warm the bear. The fur and blubber layer, which can be 4.5 inches thick, insulate the bears so well that they experience almost no heat loss. Prone to overheating, a bear will perform tricks to cool itself such as lying on its back and exposing its underside to the cold air.

Culver Trap
Culver Trap
The wildlife officers need to maintain a separation between the great predators and humans living in Churchill. One way to do this is to catch bears with a Culver Trap. An attractant, like seal oil, is placed inside the cylinder. When a bear climbs in and yanks the bait, the back door drops and the trap is sealed. When used, the Culver Trap eliminates the need for tranquilizing the bears with a dart gun, a method called free-ranging.

Face to Face
Face to Face
Ewan McGregor meets a bear face-to-face. One rule given to visitors: Don't try to make eye contact with the bears. They perceive that as a sign of aggression and may respond in kind!

A Solitary Animal
A Solitary Animal
Though playfully jousting here, bears are very solitary animals and are rarely observed interacting with one another apart from mating season. However, a family structure maintains intact for the bear's first 30 months. Cubs will drink their mother's milk and depend on her for survival. Once a bear survives to mature adulthood, it has an excellent chance of living 25 years in the wild. In fact, mortality rates are as low as 5 percent for adult polar bears. On NATURE, we see polar bears roaming arctic Canada, but they are also found in the U.S. (Alaska), Russia, Greenland, and Norway.

Bear Airlift
Bear Airlift
What might, at first blush, look like two giant white furballs are actually polar bears being flown up north after being captured and tagged by conservation workers. Polar bears are dangerous animals and thus are tranquilized so that they remain aware of their surroundings but unable to react to them for about an hour. This provides just enough time to fly the bears thirty miles north so they can be released onto the fresh sea ice. Do the bears enjoy the view from above? Probably not, as their eyes are typically covered with Vaseline to provide protection from wind and cold during the flight.

Polar Bear Capital
Polar Bear Capital
Known as the "polar bear capital of the world," the town of Churchill in Manitoba, Canada, with its approximately 800 permanent residents, is perched on a spit of land between the western shore of Hudson Bay and the Churchill River. For centuries, this peninsula has been the polar bear's natural point of access to the bay. After a summer of fasting on land in which the bears can lose half their body weight, the bears make Churchill their autumn stopover while waiting for the sea to freeze.

Ewan McGregor
Ewan McGregor
Known best for fighting the dark side of the force in STAR WARS, actor Ewan McGregor comes to Churchill to see polar bears for himself. An engaging personality and hardy adventurer, Ewan throws himself into his work by entertaining the locals, inspecting bear traps from the inside, and coming face-to-face with several of the giant animals.

Halloween
Halloween
While Ewan McGregor has some fun with local kids on Halloween, the night is actually Churchill's most dangerous. It's the perfect time of year and the perfect occasion for bears and humans to come into dangerous contact, so conservation workers are exceptionally vigilant about looking for bears who have roamed too close to town.

On the Hunt
On the Hunt
Here we see a bear hunting for its primary food source -- the seal. When the ice is frozen for the winter, the bears can roam freely and hunt for prey. One emerging problem, however, is the slow rise of average temperatures over the past few decades. This results in increasingly longer summers and slower freezing ice. The end result: bears become trapped on land and have to wait longer to roam the ice and hunt for food. For some, the wait can prove to be fatal.

Photo Essay: Explore the Town of Churchill