These secretive predators are built for survival in frozen northern landscapes. Can they adapt to a warming world?
. Of the group’s nonaquatic members, the wolverine has the heaviest skull, thickest jaws, biggest teeth, largest body, and largest feet. A single gulo can bring down prey as large as an adult caribou, and unverified reports describe wolverines occasionally forcing wolves and even big bears away from a carcass.
The last thing a wolverine is, so it would seem, is vulnerable. But trappers, hunters, and livestock owners erased the animal from much of Eurasia. In the New World, government-sponsored predator eradication campaigns took a heavy toll. By the 1930s the species had disappeared from the lower 48 states.
Yet wolverines are tenacious survivors that still have strongholds in Alaska and parts of western Canada. As predator poisoning was phased out during the 1960s, wolverines from the Canadian Rockies started to recolonize Montana’s high country and spread to parts of Idaho and northern Wyoming.. Today breeding groups live in four states: Montana, Idaho, Wyoming, and Washington, but the population remains small. A recent estimate put the number of wolverines south of Canada at around 300 animals.
A wolverine in northern Montana is one of only about 300 living in the contiguous U.S. Climate change threatens to isolate the vulnerable population, but efforts to protect it under the Endangered Species Act have stalled.Meanwhile, populations on both sides of the U.S.-Canada border face a variety of threats.
. If climate change continues as predicted, wolverines could lose one-third of their present range south of Canada by 2050, and two-thirds before the end of this century.