The future is looking more and more bleak for the wildlife of the Arctic, especially the polar bears. These bears rely on the sea ice to hunt their favorite prey, seals, and this large male bear seen here, seems to be looking across the Arctic in disbelief as his world disappears beneath him.

Photo by: Chase Dekker Wild-Life Images

Chase Dekker Wild-Life Images

Why are Polar Bears Facing Severe Weight Loss and Having Fewer Cubs?

Here's what we can we do on International Polar Bear Day to honor and protect the species.

February 26, 2020

Polar bears might be the largest predators on land but as global temperatures continue to rise and sea ice melts at an unprecedented rate, they're also one of the most vulnerable species in the world.

In fact, research led by the University of Washington between 2009 and 2015 found that a particular subpopulation of polar bears around Baffin Bay have experienced severe weight loss since the 1990s when the population was last tracked.

The reason for this? Melting ice caps. When sea ice completely melts in the summer, polar bears are pushed ashore for an extended period of time until the ice reforms. But now ice caps are melting earlier and reforming later, meaning that the species is forced to spend more time on land. Indeed, UW's study found that polar bears are spending 30 days more on land (90 days total) per year than they did in the 1990s.

Polar Bears Need Our Help 01:08

Polar bears are the largest predators on land. Their diet consists mainly of seals which they hunt for using sea ice caps. Rising global temperatures are melting ice caps and making it difficult for polar bears to hunt. Polar bears are spending more days on land than they ever have before.

Simply put, more time on land means less time spent in the water hunting for seals and other prey. During this period of food scarcity, polar bears are forced to rely on nutrients and energy stored within adipose body tissue to survive. As a result, body weight declines at a rate of approximately 1 percent per day until sea ice levels rise again in late fall and winter when polar bears can go back to hunting.

On top of this, the researchers found that reduced sea ice availability and body weight significantly affect reproductive success, with longer ice-free periods leading to smaller litters. Based on these findings they predicted that two-cub litters — which have until now been the norm — are going to become rare in the next few decades.



Canada, Manitoba, Adult Polar Bear (Ursus maritimus) sitting along shoreline with two young cubs at Hubbart Point along Hudson Bay on summer morning

Photo by: Paul Souders

Paul Souders

The impossibility for polar bears to meet their high energy demands and reproduce successfully is resulting in a rapid population decline. The species is expected to decline by a third by 2050, along with thousands of other species whose habitats are affected by climate change.

Scientists believe that only human intervention can save the species from extinction. In line with the University of Washington's findings, author Eric V. Regehr says, "Over the next century, the conservation of polar bears will depend not only on our ability to understand and quantify the effects of climate change but also on our capacity to predict how climate change will influence viability and adjust management actions accordingly."

6 Ways to See Polar Bears in the Wild

See All Photos

So what can we do on International Polar Bear Day to honor and protect the species? Here are a few ideas...

Learn more about the species. For example, did you know that polar bears can smell prey up to 20 miles away?

Live more sustainably. We can all work towards slowing climate change down. Use your car less and walk or use public transportation more often instead. Minimize waste and consumption—reduce, reuse, and recycle.

Vote. Vote for politicians who understand the reality of climate change and have plans to make a difference. Encourage friends and family to vote too.

Donate and Volunteer. Support foundations and environmental protection agencies that encourage taking action towards sustainability, educating others, and polar bear conservation.

How will you celebrate International Polar Bear Day?

Next Up

Why Islands Have The Most Unique Creatures on Earth

What is it about islands that makes scientists weak in the knees?

Here's Why Your Cat Sticks Its Butt In Your Face

Contrary to popular belief, cats do like some people.

Why Islands Have the Most Beautiful and Unique Creatures on Earth

Places like New Zealand, Austrailia, Hawaii, and the Galapagos give us major wanderlust. But what is it about islands that make scientists weak in the knees?

If Cicadas Come Out Once Every 17 Years, Why Do You See Them Every Summer?

These mysterious insects have one of the strangest life cycles in the natural world.

The “Lungs of Our Planet” are Under Threat

World Rainforest Day is June 22, bringing awareness and action to save these precious ecosystems. But if the current rate of deforestation continues, will there be any rainforests in 100 years?

Through the Eyes of Nature: What Animals Can See That We Can't

When scientists began looking closely at a moth’s eye they discovered a nanostructure on the surface of their eyes, which were named the corneal nipple-array. Those tiny little structures essentially assisted the moth in gathering light from the surrounding world it flies through.

The Stegosaurus Was An Ancient Relic To The T. Rex

These two popular dinosaurs never crossed paths.

This Giant Ichthyosaur Might Have Been Bigger Than a Blue Whale

This normal-looking reptile may be the largest animal that ever existed.

Wombats: The Furry Heroes of the Australian Wildfires

Wombats dug craters which tapped into deep-flowing water, providing vital resources to fauna and fellow animals.