The Fuzzy Face of Climate Change
Is a picture always worth a thousand words?
Without a doubt the polar bear, beleaguered in a world rapidly changing by global warming has become a powerful image for environmentalists. However, the polar bear has proved to been remarkable in it’s adaptation to the changing surroundings. Once thought to be an endangered species, the white giant has made a comeback even while suffering setbacks. That isn’t to say there have not been changes in the polar bears behavior- there have been.
Polar bears are adapting to a very different world, one profoundly changed by global warming. While this is heartening, there is no way to know if this adaptation can continue- and there is no way to know if other species will be able to replicate the success of the polar bear. The success of one species to adapt to a changing environment no guarantee for the rest of us.
On January 24, 2004, in the frigid moonscape of an Arctic winter, wildlife biologist Steven Amstrup rode in a helicopter flying low over the ice. Using an infrared heat detector, he hoped to find polar bears in their dens. When the gun recorded a hit, Amstrup circled around for a closer look. What confronted him was something he had never seen in 34 years of research. The mouth of the den was open, and a smear of bright-red blood stretched away for more than 200 feet. At the end of a long drag trail in the ice lay the still-warm body of a female polar bear. The air temperature was 20 degrees below zero; this bear could not have been dead for more than 12 hours.
Polar bears do not have enemies. A male can weigh 1,500 pounds, with paws a foot wide and savage teeth. They are the unchallenged master predators in the harshest environment on Earth. A full-grown bear slaughtered in her den is far outside the ordinary.
Amstrup and his team returned by snowmobile. The dead female had multiple wounds to her neck and head, and the snow was stained by heavy arterial bleeding. Her skull had been pierced by a long tooth that slammed into her brain. Her hindquarter, belly, and mammaries were partially eaten.
Inside the den, Amstrup found two tiny cubs, each weighing less than five pounds. Both were dead, suffocated by the thick snow of the ruined cave. A single set of massive footprints led directly to the den. The footprints followed a typical hunting pattern—the stalker meandered around in a wide arc, then beelined for the spot where the mother and cubs were resting. There was only one explanation for this carnage: the bear and her cubs had been killed by another polar bear.
Cannibalism is not normal polar bear behavior. Seals are easier to catch and their meat has more calories per pound than bear meat. But over the course of that single season, Amstrup witnessed two additional instances of cannibalism. Having never seen anything like this, he was shocked to stumble across three separate incidents in one year. But as he spoke to colleagues, he found that cannibalism was becoming more common. In the Svalbard Archipelago, 450 miles north of Norway, three small cubs had been found dead inside their den. Although polar bears sometimes kill each other, these were the first recorded instances in which the killing took place at the supposedly safe haven of a den.