A Vanishing Home


20,000-25,000 polar bears live in the coastal and offshore zones of Canada, Alaska, Russia, Greenland and Norway.

Their habitat is disappearing. Climate change is effecting the Arctic faster than anywhere on the planet, and the polar bear, like the canary in the coal mine, is a living signal of the harmful changes in the environment.

Polar bears are incredibly strong and resourceful. They can overcome scarce food, long swims, extreme cold, and attacks from predators.

But climate change is something they can’t deal with. Polar bears are thinner because they don’t have as much sea ice to hunt from, cub survival rates are down, and their population is dwindling.

Sylvia Earle on the Arctic

OWOO Science Advisor and Nat Geo Explorer in residence Sylvia Earle on this critical moment in history for the Arctic.


"when you take away the habitat of an organism, you lose the organism. if you lose the sea ice, it's pretty clear that you are going to lose (polar) bears."

-Dr. Andrew Derocher,
Chair of IUCN Polar Bear Specialist Group

Troublesome Facts


World polar bear population will likely drop by two-thirds by 2050, and may disappear entirely from Alaska, only remaining in pockets off north Greenland. (US Geological Survey)

The population has already dropped 30% in the last 45 years, and the IUCN has put them on the vulnerable species list, one step below endangered.

Polar bears in Hudson Bay weigh 15 percent less than they did 30 years ago. Underweight bears have higher mortality rates, less success mating, and cubs are less likely to survive.

Contributing Factors

Disappearing Sea Ice
Humans
Pollution
Other Bears

Polar bears hunt seals from sea ice. When it melts, the bears are stranded on land where they often go without food for months until winter brings ice again. The duration of sea ice is critical to surviving through summer. The sea ice in Canada breaks up 3 weeks sooner each year than it did 30 years ago.

"They are losing about 3 of the best weeks for feeding on the ice, when the seal pups are the most abundant and they can put on the fat that they store and then live off of," said Dr. Ian Stirling, with the Canadian Wildlife Service. "(There is a) direct relationship between the date of the ice break-up and survival," he added.

The ice also recedes farther off shore each year. It now recedes up to 180 miles out. A longer swim costs precious energy for polar bears that are already weak at the end of a long summer, and in 2006 researchers recorded four drownings, unprecedented among these exceptional swimmers.

3 of the past 4 years have had the lowest recorded ice packs in Alaska's Beaufort Sea, pushing more polar bears onto land. There the bears find their way to garbage dumps and other places where encounters can be harmful for humans and bears alike. Mother bears making their dens on land have a tougher time surviving too.

So many polar bears have been moving into Russia's Chukotka region due to lack of sea ice that the government legalized polar bear hunting last March despite a ban since 1956.

Some of the most toxic industrial chemicals, dioxin and PCBs, come north in the atmosphere, end up in Arctic waters, and take many years to break down. They accumulate in Arctic animals, mainly in the high end of the food chain. Many of the chemicals bond to fat molecules, which is tough on polar bears because they eat a high-fat diet. Researchers have found high levels of toxins in polar bears, the ringed seals they eat, fish, beluga whales, walrus and Inuit people too!

A recent report issued by Dr. Steven C. Amstrup, team leader for a US Geological Survey polar bear study in Alaska, shows evidence of polar bears eating other polar bears in the southern Beaufort Sea, Alaska.

Although polar bears were previously known to occasionally kill others' cubs—attempts at this are featured in To The Arctic - competition for scarcer food and being pushed into closer proximity may have resulted in more cannibalism.


The Silver Lining

Some of the world’s top biologists are working hard to preserve these animals and their habitat. Here is a field report about their work. They have the knowledge to help the polar bear. All they need now is public support.

Help Protect the Arctic!