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Cover Story - Spanish Version

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Feeling the Heat

Spanish Translation

-By Kathryn R. Satterfield

Polar bears thrive environments too harsh for most animals. For much of the year, they live and hunt on the frozen Arctic sea ice. Nature has prepared them for the harsh conditions. But nothing has prepared the bears for the danger that threatens the only home they know.

The polar bears’ world is melting. Studies show that the permanent polar ice has declined by 9.8% every 10 years since 1978. Scientists blame global warming for the shrinking polar ice. They say that climate change is harming polar bear populations.

Two weeks ago, the U.S. Department of the Interior said that it was taking steps to list the polar bear as a threatened species under the Endangered Species Act. The action came on the heels of a World Conservation Union decision to move polar bears to threatened status on its Red List of Threatened Species. The World Conservation Union warns that polar bear populations could fall by 30% over the next 45 years.

A Bear of a Problem
Scientists estimate that 20,000 to 25,000 polar bears live in the Arctic. They are spread across five countries. Approximately 4,700 of the bears live in the U.S., within Alaskan waters.

Polar bears depend on the sea ice for their survival. Seals, their main prey, breed on the ice. “The sea ice is more than just this platform that the bears walk over,” says Andrew Derocher, a scientist who studies North American polar bear populations. “Without it, they can’t exist.”

Some melting and refreezing of the polar ice is natural. But in a warmer world, these cycles speed up, and bears have less time to hunt. Normally, they have three months in the spring when they pack on the pounds. The extra fat is used later, when the bears are not actively hunting. Pregnant females depend on this stored fat to nourish their cubs.

Since the early 1990s, scientists have seen a drop in polar bears’ body weight. Fewer cubs are being born, and fewer survive. In Canada’s Western Hudson Bay, the polar bear population dropped 22% from 1987 to 2004.

To Protect and Save
The Department of the Interior has a year to make its final decision. If the bears gain threatened status, the department will work with businesses and international officials to set strict rules to protect the bear and spur its recovery.

The polar bear’s plight may seem distant to some. But Derocher told TFK that it is up to this generation to stop global warming and its dire consequences. He urges kids to think about what they can do to help the environment. Even simple steps—turning off the lights, walking instead of riding in a car—can really make a difference. “I’m optimistic about humans’ ability to deal with this,” he says.

More Trouble Ahead?

Global warming is pushing many species toward extinction. Here are some animals that especially worry scientists.

Butterflies
Researchers have tracked how the ranges of many butterflies are shifting and, in many cases, shrinking. In the U.S., scientists are studying the movements of the butterfly known as Edith’s checkerspot. Though butterflies are sturdier than they look, scientists believe many species will not survive the impact of climate change.

Red-Breasted Goose
More than two dozen bird species—including this goose, which breeds in the Arctic—are officially threatened by global warming. Half are seabirds whose food supplies are smaller because of climate change. Other coastal species are at risk because of rising sea levels.

African Elephant
Global warming threatens to shrink the elephant’s range in Africa. Climate change also affects its food supply.

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