Polar Bears: Majestic Creatures of the North

Standing up to nine feet tall and weighing in over one thousand pounds, polar bears are the largest land carnivores in the world. While polar bears are part of the bear family, including brown and grizzly bears, these enormous mammals have evolved incredible and unique adaptations to survive life in the frigid waters of the Arctic and surrounding landmasses, the only region in the world where polar bears exist.

© Carrie Vonderhaar, Ocean Futures Society

Their iconic white coats are a means to disguise themselves against the backdrop of their frozen snow-covered hunting grounds. In the Arctic’s chilly temperatures, often well below freezing, polar bears are designed for warmth. They wear a dense layer of underfur, have black skin to absorb the sun’s energy rays, and carry a layer of blubber beneath their skin, insulating them from the Arctic temperatures both on land and at sea. In fact, a polar bear running on land will easily become overheated, and many land animals are too fast for polar bears to successfully hunt. Instead, polar bears turn to the sea.

© Carrie Vonderhaar, Ocean Futures Society

Superb hunters, polar bears are the most carnivorous of all bears. Seeking the calorie-rich fatty blubber of Arctic seals, polar bears have evolved to survive in snow, sea ice floats, and even open water. While hungry polar bears will opportunistically eat whatever they can, including massive animals like the walrus, belugas, and narwhales, their main source of prey are seals, which spend their entire lives either in the water or on seasonal ice floats. In order to find their food, polar bears must follow their prey and venture into the Arctic Ocean. Using their excellent sense of smell, they can locate a seal’s breathing hole in the ice, and then patiently wait for a seal to return to breathe before striking its attack, a method known as still-hunting. Due to their extended periods of time out on Arctic sea ice, polar bears are considered marine mammals. Their scientific name, Ursus maritumus, which means “maritime bear,” reflects these creatures devotion to a life at sea.

© Carrie Vonderhaar, Ocean Futures Society

The Arctic is unique among Earth’s ecosystems. It is made up of the northern regions of the American, European, and Asian continent, and to a large extent consists of annual sea ice that extends from these landmasses into the Arctic Ocean. This annual sea ice is where the seals forage, haul out to rest, give birth, and hide their young – and consequently, where the polar bears come to follow their prey. Due to human activities, the average global temperature of the planet is increasing, causing sea ice to melt earlier and earlier each year. Less sea ice each year means less opportunity for polar bears to find food and build enough fat storage to sustain them for the rest of the year. On top of shifting climate patterns that disrupt natural hunting behaviors of polar bears, other human activities that threaten these magnificent creatures include pollution, increasing oil and gas development in the Arctic, and increasing shipping traffic across the North Pole as sea ice continues to melt. Found in nineteen subpopulations throughout the Arctic, forty percent of the entire population of polar bears are in decline.

© Carrie Vonderhaar, Ocean Futures Society

Playful, inquisitive, and picturesque, polar bears are an iconic species in wildlife conservation. As top predators, their abundance and health signify the health of the entire Arctic ecosystem. A hardy, powerful predator, the fragility of their species in the face of climate change and other factors are reminders that every action we make has consequences – we are all connected – even to the farthest reaches of the globe.

© Carrie Vonderhaar, Ocean Futures Society

Extra Fun Fact!
Contrary to media advertisements illustrating polar bears co-habituating with penguins, in actuality, penguins and polar bears live, literally, on opposite ends of the earth. The name Arctic comes from the Greek word for bear, and polar bears are the top predators roaming the vast regions surrounding the North Pole. On the opposite side of the planet is the Antarctic, which comes from the Greek meaning “the opposite of the Arctic,” or “opposite of the (great) bear,” since there are no polar bears that live on the Antarctic continent.

© Carrie Vonderhaar, Ocean Futures Society