Are Polar Bears Really as Doomed as We Say?

With global warming and melting ice, it isnít easy being a polar bear anymore. Some studies have predicted that polar bears could very well be extinct by the end of the century. The good news is not all researchers think the bears are absolutely doomed. Scientists at the American Museum of Natural History (AMNH) have published a new paper indicating that things might not be as bleak for polar bears as their peers expect.

To understand the reason for the researchersí cautious optimism, we must first understand the factors that are threatening the polar bearís existence. Polar bears consume a diet of mainly young seals. In order to hunt these seals, polar bears need to rest atop sea ice Ė the same ice that is increasingly melting for most of the year thanks to climate change. In another 50 years, experts expect that the Arctic will be too warm for sea ice to form for half of the year, leaving polar bears without a reliable food source and in serious danger of starvation.

As it turns out, alternative food sources for the polar bears arenít completely out of the question. For as long as biologists have tracked the animals, theyíve recorded instances of polar bears eating animals found on land like caribou and snow geese Ė as well as the snow geeseís eggs. ďPolar bears are opportunists,Ē stated Robert Rockwell, a researcher with AMNH.

Can polar bears actually survive off these alternative food sources for long periods of time? To figure this out, researchers calculated the nutrients that a caribou and snow geese diet would provide. They found that even adult male polar bears would be able to obtain more calories than they would burn in hunting these meals. Moreover, the food would provide the sustenance necessary to avoid starvation during the summer months.

Unfortunately, not all polar bears have demonstrated a tendency to seek prey on land. That said, the researchers expect that necessity would push more polar bears to hunt on land to avoid starvation. They also expect that the bears could learn from their fellow bears how to hunt on land until the practice becomes second nature.

As it stands, the AMNH scientists arenít willing to make any promises about the future of the creature. Since we have yet to see polar bears eat caribou on a large scale, the researchers canít project whether the bears will make the necessary adaptations on their own accord. Given what we do know about polar bearsí potential for adaptability, though, it seems premature to count them out.

Since news of global warming became mainstream, polar bears have become one of the mascots of the environmental movement. Anyone who thinks the well-being of polar bears is the only compelling reason to combat climate change isnít paying attention, though. Besides, the researchers themselves have pointed out that slowing the effects of climate change could be critical to the polar bearís survival anyway. The more we can delay the melting of Arctic ice, the longer bears will have to learn how to subsist of land creatures.

The polar bearís future may be uncertain, but for the animal lovers among us, itís good to have some optimistic news about the creatureís prospects. Itís a shame that itís taking so long for humans to get their act together when it comes to the environment, but if polar bears can find a way to withstand our carelessness, more power to them!

Photo credit: Thinkstock

101 comments

Siyus Copetallus
Siyus C2 years ago

Thank you for sharing.

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Patricia Harris
John Taylor2 years ago

Not while we here to save the day!!

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Dan Blossfeld
Dan Blossfeld3 years ago

Latest estimate of polar bear populations have been revised upwards:

http://polarbearscience.com/2015/05/31/global-polar-bear-population-size-is-about-26000-20000-32000-despite-pbsg-waffling/

It appears that the paper may be onto something.

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Paulinha Russell
Paulinha Russell3 years ago

Thank you

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Sarah Crockett
Sarah Crockett3 years ago

Thanks for sharing.

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Miriam VOICEfortheVOICELE
Miriam AWAY S3 years ago

Thanks for sharing! YES.

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Dan Blossfeld
Dan Blossfeld3 years ago

Jonathan Y.,
What do you mean by melt boundary? According to NSIDC, last years ice extent was the 7th lowest in the last 8 years.

http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/

Also, can you expand on what you mean by dying off? This article and others indicate that no such change has been observed in polar bear populations. In fact, polar bear numbers appear to have risen over the past decade, building on gains made over the previous three decades.

http://www.canadiangeographic.ca/magazine/dec12/polar_bears.asp

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Nimue Pendragon

oh yeah they are if we do nothing

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Nimue Pendragon

oh yeah they are if we do nothing

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Jonathan Y.
Jonathan Y3 years ago

Another factor is polar bears' ability to interbreed with Ursus Arctos, to which they're closely related. DNA studies show Polar Bears and Brown Bears have interbred back into prehistory, so their speciation is not sharply demarcated. The offspring are fertile. So even in a much warmer world, some polar bear genes will survive. Both species are extraordinarily resilient and versatile, and interbreeding will lead to hybrid vigor.

This doesn't diminish the tragedy of what's happening in the Arctic, which is experiencing record warming. Entire populations of polar bears in the far north who specialize in ice-floe hunting will continue dying off as they have been, with the pups starving first. The Arctic Ocean will soon be gone in summer; last year's melt boundary was the smallest ever

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