Are Polar Bears Endangered?

Polar bears and other Arctic species are particularly at risk because their habitat is increasingly threatened by global warming.Over the past three decades, more than a million square miles of sea ice -- an area the size of Norway, Denmark and Sweden combined -- have disappeared. Scientists predict that 80 percent of the summer sea ice that polar bears depend on for survival could be gone in 20 years, and all of it by 2040. As a result, the world's polar bears could face global extinction by the end of this century.

The polar bear has been reclassifed as vulnerable on the IUCN World Conservation Union's "Red List of Threatened Species," noting that the species could become extinct due to sea ice changes. Already, more than 25 percent of the world's polar bear populations are in decline.

Polar bears spend most of their summers roaming the Arctic on large chunks of floating ice. They drift for hundreds of miles, finding mates, hunting for seals and fattening themselves up for the winter. Without these thick rafts of sea ice, the world's largest bear could not survive. Yet at this moment, the polar bear's Arctic habitat is literally melting away beneath it due to global warming.

Pack ice overall is decreasing globally. When pack ice does form, it melts more quickly, and tends to be thinner as well. In 2004, several polar bear deaths by drowning were recorded, something which was hitherto unheard of. The polar bears had been trapped on isolated areas of floating ice, and had tried to swim for land. Due to the shrinkage of the ice, the polar bears tired and drowned before reaching shore and safety. This problem will only grow as the pack ice shrinks.

The shrinkage of the ice has other repercussions for polar bears. They are losing their natural prey, who are also affected by the shrinkage in habitat. Polar bears are not very adept at catching land animals. Land animals also do not provide the high fat diet that polar bears need, which will lead to starvation. Starving mothers will not be able to provide their cubs with the nutrition they need, which will further contribute to the decline in polar bear numbers.

While searching for food and habitat, polar bears have also clashed with humans. Interactions with polar bears used to be very rare, because the bears kept to the sea ice. With the disappearance of the sea ice, polar bears have begun to show up around inhabited areas looking for food and shelter. They contend with hunters for their kills and often end up being slaughtered because they pose a threat to human communities.

Evidence of the dire impact of global warming on polar bears continues to mount. That evidence includes polar bear drownings, cannibalism, starvation, reduced cub survival and denning dislocation.

• Polar bears are one of the world's strongest swimmers but four were found drowned in the Bering Strait. Scientists believe that as many as 27 may have perished.


• Two female polar bears were found starved to death, without any fat stores.


• Newborn cubs were crushed to death when their snowy dens collapsed from unseasonable rains


• A majority of pregnant polar bears in Alaska are now digging snow dens on land rather than on sea ice.

The combination of deadly factors brought about by global warming put polar bears at a very high rate of risk. Drops in birth and survival rates have already been documented, and biologists are growing concerned about erratic behavior exhibited by polar bears as a result of the loss of their natural habitat. Organizations dedicated to the welfare of the environment believe that a global effort is needed to counteract global warming before it is too late for polar bears, as well as many other species that call Earth home.

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