The polar bear is both the largest bear and the largest land carnivore in the world. Males can weigh up to 800 kilograms and reach three metres in length. They live throughout the ice-covered waters of the Arctic, found in Canada, Greenland, Russia, the United States (Alaska), and Norway.
Some of the most amazing polar bear facts involve their physical appearance. Their skin is black, and they have thick translucent fur that reflects visible light, appearing white to our eyes. They have blue tongues and giant paws the size of dinner plates—about 30 centimetres wide.
Polar bears evolved from brown bears as recently as 150,000 years ago, and the two species can still interbreed. The results, known as “grolar bears” or “pizzly bears,” physically resemble both species and are usually born to polar bear mothers and raised as polar bears.
Unlike brown bears, polar bears don’t need to den during the winter because their food sources are available year-round. Pregnant females, however, will make dens to create warmer environments for their cubs, who are too small to survive the intense cold.
After giving birth, a mother polar bear uses her fat stores to produce milk for her young before teaching them to hunt. Cubs stay with their mothers for as long as three years before becoming independent.
Polar bears sit at the top of the food chain in their ecosystems and help maintain the health of their environments. They also serve as an indicator species, helping us keep track of the effects of climate change on sea ice and the life it supports.
What is a polar bear's scientific name?
The polar bear’s scientific name is Ursus maritimus, which means “sea bear” in Latin. This refers to their swimming skills, the sea creatures they hunt, and the sea ice on which they spend much of their lives. Polar bears are also classified as maritime mammals because of the webbing on their feet.
Are polar bears endangered?
The IUCN has classified polar bears as “vulnerable” for most of the past 40 years, though concrete data on their population numbers isn’t readily available. Of the 19 subpopulations of polar bears globally, one is increasing, five are stable, and four are in decline. The remaining nine have insufficient data.
Pollution, hunting, and human commercial activities all pose a threat to polar bear populations, but climate change is the most severe issue they face.
Where do polar bears live?
Most polar bears live north of the Arctic Circle, though some populations exist in more southern areas, such as the Hudson Bay of Manitoba in Canada. Alaska, Russia, Greenland, and northern Norwegian islands are also home to polar bears.
Polar bears’ habitats consist of sea ice and nearby coasts where pregnant polar bears den. Male polar bears will also spend time on land during warmer months when much of the sea ice has melted.
There are several threats facing polar bears that experts predict will become more severe in the near future. Most of these concern the polar bear’s natural sea ice habitat, which is threatened by climate change and increased human presence.
Sea ice is essential to the polar bear’s way of life, as it’s where they hunt most of their prey. It is particularly important for a female polar bear, who must store enough fat to sustain both herself and her young while the cubs are too small to leave the den. If she cannot hunt enough food before giving birth, she will run out of nutrients, and her litter won’t survive.
Unfortunately, Arctic sea ice loss has progressed much faster than many experts predicted. So far, over 770,000 square miles of sea ice has been lost, and ice cover continues to shrink by 14% each decade.
Pollutants from human activity reach the Arctic Circle by air, ocean currents, and river runoff. While the effects of these pollutants are still uncertain, we know that polar bears are exposed to the highest levels of toxic substances because they are apex predators. As pollutant levels compound with each step in the food chain, each animal consumes the pollutants to which its prey was exposed.
Current research fears that pollutant levels in some subpopulations of polar bears may interfere with hormone regulation, immune system function, and reproduction.
Human commercial activities
As rising temperatures melt sea ice, they also open up previously inaccessible areas to human development. Tourism, shipping, and proposed exploration projects will intrude on polar bears’ range and affect their survival.
Excessive human development could affect food availability, increase the level of pollutants in the area, and increase the chances of human-animal conflict.
When polar bears are forced to spend more time on land rather than on sea ice, they are drawn to human settlements. Their strong sense of smell can help them find sources of meat and prey up to a kilometre away, and the smell of dogs, garbage, and stored food from human communities can attract them.
When this happens, humans often respond with lethal force, as polar bear attacks can be catastrophic for humans and their property. If human activities in polar bears’ range increase, it will likely lead to higher levels of conflict.
What do polar bears eat?
Polar bears, unlike most other species of bear, are primarily carnivorous and prey on ringed seals and bearded seals as their main food sources. Seal blubber is ideal for polar bears because they need to maintain a thick layer of fat to stay warm and feed their young.
They hunt by waiting on sea ice for the seals to surface for air. They also search for seal pup dens in the ice, using their sense of smell to locate them.
However, hunting success rates are very low, and it’s common for polar bears to scavenge from other sources when necessary. They eat whale and walrus carcasses and search for bird eggs and other food sources.
Do polar bears hibernate?
Other species of bears hibernate because food is scarce in the winter, and snowfall can make traversing their habitats difficult.
For polar bears, however, winter is the best time to catch their blubbery prey. More ice means a slower escape for seals after coming up for air, allowing polar bears a better shot at catching them. Because of this, polar bears don’t hibernate at all.
In fact, they get most of their hunting done during the winter, building up as much fat as possible to last during the summer months when food is more challenging to secure.
How much does a polar bear weigh?
A male polar bear can weigh up to 800 kilograms or around 1,700 pounds, which is roughly the combined weight of 10 human men. Females are much smaller, usually weighing 460 kilograms or 1000 pounds. After a successful hunting season, when polar bears have stored their maximum amount of fat, they can weigh up to 50% more than usual.
How tall is a polar bear?
The length of a polar bear from nose to tail can reach up to three meters or eight feet.
What colour is a polar bear's skin?
Although polar bear cubs are born with pink skin, it turns black at 3-4 months. Scientists are unsure why the change happens, but most theories are connected to the sun.
Black absorbs heat from the sun more effectively, potentially helping polar bears stay warm in their cold habitat. Dark skin is also more resistant to UV rays. This is useful for polar bears since sunlight intensifies when it reflects off of snow, sea ice, and water.
What colour is polar bear fur?
The polar bear developed its signature “white” fur to help it adapt to colder environments when it split off from its brown bear ancestors. Though we see polar bear fur as white, it’s actually translucent, meaning it lacks colour and is partially see-through. It’s also hollow, and the result of these features is that the hairs scatter and reflect visible light, creating the effect of a white pigment.
How long do polar bears live?
Polar bears live for around 25-30 years in the wild.
How many polar bears are left?
According to the IUCN, there aren’t many facts about polar bear numbers, but some sources estimate around 26,000. Currently, it seems their numbers have not been severely impacted by humans or climate change, but both problems could potentially wipe out polar bears quickly if we don’t put safeguards in place.
How can you help?
Polar bears are vulnerable due to the growing threats they face, including climate change, pollution, human commercial activity, and human-animal conflict.