Above: Image © id-work, iStock

At first glance, the Arctic may look like a desolate, unforgiving place where no living thing could survive. After all, the environmental conditions can be pretty harsh above the Arctic Circle. In the far north, both nights and days can be bitterly cold and dark. But not only do many people live there, the Arctic also supports many unique forms of animal life.

Fish, seals, whales, birds and many other organisms call the Arctic home. These animals have features that help them thrive in the Arctic. But the reverse is also true: many of these creatures depend on Arctic conditions to survive.

Climate change could cause big trouble for some of these animals. Let’s look at two examples: polar bears and narwhals.

Did you know? Scientists believe people may have been living in the Arctic as far back as 15,000 years ago.

Polar Bears

When you think of Arctic animals, what comes to mind? For many people, it’s polar bears. These animals have some cool features that help them survive the Arctic cold. For example, underneath all that white fur, they have black skin, which helps them absorb heat and stay warm.

A young polar bear
A young polar bear in Alaska’s Arctic National Wildlife Refuge (Alan D. Wilson, Wikimedia Commons).

Polar bears spend at least part of their life in the ice-covered waters of the Arctic. That’s why scientists classify them as marine mammals, like whales and seals. They’re powerful swimmers, with large amount of stored fat to help them float, large paws to paddle with and strong back legs to use as rudders.

Because they spend so much time in the water, polar bears rely on Arctic ice cover. They use sea ice as a platform from which to hunt, mate and travel. And polar bears mainly feed on ringed and bearded seals, which also depend on sea ice for hunting and rearing pups.

Did you know? Polar bears normally have a lifespan of between 25 and 30 years in the wild.

Narwhals

Meanwhile, narwhals are highly social, toothed whales found only in the Arctic Ocean. Males have a tusk coming out of their heads, which is why narwhals have been nicknamed “the unicorn of the sea.” The tusk is actually an extra-long tooth with some feeling. Males sometimes cross tusks with each other. Scientists think they do this to determine their social hierarchy and compete for females.

Like polar bears, narwhals depend on ice cover. They migrate seasonally between their wintering grounds (mainly Baffin Bay and northern Davis Strait) and summer ranges (mainly Greenland and Baffin Island).

Changing ice conditions tell narwhals when it’s time to migrate. In the summer, they stay close to shore. When fall arrives, ice begins to cover these areas, threatening the narwhals’ ability to hunt. This is when they migrate offshore and settle in at their winter grounds. Dense ice packs form in these areas, too. But the animals can continue to hunt because of gaps in the ice.

Travel and food access aren’t all that narwhals use ice coverage for. In the spring, female narwhals rely on dense ice cover to safely give birth!

Did you know? The polar bear is one of the world’s largest species of bear. Males can weigh up to 680 kilograms (1,500 pounds)!

Arctic animals and climate change

As you can see, the lives of both of these animals are deeply connected to ice cover. But global temperature increases will reduce the amount of ice in the Arctic. This could make the future very uncertain for polar bears, narwhals and many other species that depend on ice.

Reduced ice cover might lead to other threats, too. Less ice will make the Arctic more accessible for human activities like tourism and oil exploration. How do you think these activities could affect animals like polar bears and narwhals?

Learn more!

Footprints of climate change in the Arctic marine ecosystem (2010)
Paul Wassmann et al., Global Change Biology 17.
Link to abstract. Registration of subscription required to view full text.

Polar Bear (Ursus maritimus) Life History and Population Dynamics in a Changing Climate (2009)
E. Richardson, Arctic 62

Polar Bear
National Geographic

Narwhal FAQ.
K.L. Laidre

Narwhal Whales
NOAA Fisheries

Lushani Nanayakkara

Lushnai Nanayakkaea

Originally from Colombo, Sri Lanka I did an undergraduate in Zoology at Ohio Wesleyan University in Delaware, Ohio. After that I lived in Florida for a short-time working with Asian elephants. Then I moved to Maryland where I completed my MSc in Environmental Sciences and Policy at Johns Hopkins University. Wanting to experience living yet another country I moved to Canada to pursue my PhD at the University of Regina in Saskatchewan. I am currently finishing my PhD while living in Toronto. During my free time I enjoy traveling, trying new types of cuisine and attending concerts/plays and interesting lectures.







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