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Polar bears have three main tactics that help them survive in temperatures as low as -45 degrees celsius; their fur, their fat, and their surface area.

How Fur Keeps Them Warm

So, let's look at their fur. Polar bears have two layers of hair. The bottom layer is called the undercoat. These are short, wooly white hairs that trap dry air close to their body. The most unique thing about guard hairs is that they are hollow inside. The trapped air helps with insulation and provides extra buoyancy when swimming.

Excess Fat for Insulation

As the largest bear species, an adult male polar bear can be up to 3 meters and weigh between 350 to 680 kilograms. That's equivalent to about 7 refrigerators.

But, how are they so big? Well, underneath their fur and skin, they can have up to 10cm of fat. This excess fat provides insulation from the cold, and energy reserves for the summer months when food is hard to find. Polar bears mostly eat seal blubber which is very high in energy. Their stomach can hold 10-20% of their total body weight so they can eat a whopping 12,000 calories per day.

Low Surface Area-to-Volume Ratio

The final reason why polar bears don't get cold is their surface area.

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This minimizes heat loss because a smaller proportion of their body is in contact with the cold air. This is why they also have very small ears and a tiny tail compared to other bear species. The combination of their fur, fat, and surface area means that polar bears do not emit much heat like other warm blooded animals. They keep the heat inside their body which is why they appear black on infrared cameras.

In fact, they are so good at retaining heat that they risk overheating. This happens when they do intense physical activity so they have to dive into the cold ocean to cool off.

Two-thirds of all polar bears living in Canada with an estimated 16,000 polar bears, Canada has the largest population of polar bears.

3,000 to 5,000 polar bears stay in Russia with populations found in the Arctic region, including Wrangel Island.

Greenland has an estimated 2,500 to 3,000 polar bears

The United States has an estimated 3,000 polar bears, with populations found in Alaska

Norway has an estimated 2,500 to 3,000 polar bears.,

These numbers are estimates and can vary depending on various factors, such as habitat, foc availability, and climate change.

Polar bears eat a variety of fruits, including berries, cloudberries, cranberries, dewberries, gooseberries, lingonberries, and bearberries.

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