Polar bears are often mistakenly thought to live on the planet’s southernmost continent, and this frustrates many scientists. Given the similarities between Antarctica and the true home of polar bears, the Arctic, this confusion is quite understandable. So why are polar bears only found near the North Pole?
Millions of years ago, the continents of Earth were united into a single supercontinent: Pangea. The animals of the time could move through landscapes today separated by vast expanses of water. But when Pangea broke up about 200 million years ago, this mixing of species ended.
It turns out that the ancestor of today’s polar bears ended up on the continents that became Europe, Asia and North America. These ancestors gave birth to the brown bears of North America 1.4 million years ago, long after Pangea broke up. It wasn’t until a million years later that an albino evolution of the brown bear began to thrive in the Arctic, making the polar bear a relatively recent animal in Earth’s long history.
Antarctica was also part of the Pangea supercontinent, before slowly drifting south. But unlike the pieces that went north, no bear ancestor was able to make the trip south – or at least, no ancestor could survive the harsh climate of Antarctica.
Thanks to wildlife photographers like Paul Nicklen and Cristina Mittermeier, the plight of polar bears in the Arctic has come to light. Polar bears rely on the frozen ocean to hunt their main food sources: seals and walruses. Unfortunately, the rapid melting of ice in the Arctic has dramatically reduced these hunting areas, causing famine in many polar bears. Today, they are on the verge of extinction.
The disappearance of polar bears at the hands of melting ice has led some specialists to suggest that these animals be relocated to Antarctica. The amount of ice is also decreasing there, but not as rapidly as in the Arctic. But if we give polar bears solid ground, not ice, could they learn to survive?
While it is true that Antarctica has a suitable climate for polar bears and food for them, their forced migration south would be far from foolproof. On the one hand, Antarctica is largely devoid of land predators similar to the polar bear. In the absence of these types of predators, penguins and seals are not afraid when they are above water.
In fact, the first explorers to Antarctica noticed the fearless curiosity of penguins, which made them an easily accessible food source for shipwrecked explorers. If polar bears were introduced to Antarctica, penguins would be hunted without difficulty and would be in danger of extinction. The polar bear could indeed indulge in excessive hunting of Antarctic prey, which could have devastating consequences for the local fauna.
The uncertain repercussions of the introduction of polar bears to Antarctica point to a larger problem associated with this type of human intervention: the unknown. Even if scientists and conservationists find a surefire way to prevent introduced polar bears from destroying the native penguin and seal populations of Antarctica, the negative repercussions could be enormous.
There are also significant logistical obstacles to the movement of polar bears to Antarctica, since the continent is not under the control of a single country: it is managed by a treaty ratified by fifty-four countries. According to this agreement, the introduction of polar bears to Antarctica would require the unanimous support of all member states. Given how difficult it is to add marine protected areas to Antarctica to date, a controversial plan to introduce polar bears to the continent is unlikely to gain the required unanimous approval.
Global warming remains the main cause of the disappearance of the polar bear. Even if the relocation of the latter to Antarctica were without ecological consequences or international resistance, the White Continent would probably only be a temporary refuge for the species. With ice cover decreasing almost every year, Antarctica is also suffering from the effects of global warming. In the face of this harsh reality, reducing our global greenhouse gas emissions seems like the best way to give polar bears a chance at survival.
Article translated from Forbes US – Author: Liz Allen
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