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It's hard to mistake that sound. Now imagine hearing it during a night that can last for months and where temperatures drop as low as –37 degrees Celsius¹. Enough to give nightmares to musk² ox and Arctic hares, the favorite prey³ of the long-legged white wolves of the Arctic

These wolves cover a lot of frozen ground. Researchers put a GPS collar on a pack leader they named Brutus and found that he roamed as many as 41 kilometers in a 12 hour period. That includes jaunts⁴ across the newly formed sea ice between the pack's home on Ellesmere Island and adjacent islands in Nunavut. 

Of course, it would be impossible for scientists to personally track the white wolves in winter. So the collar communicates with GPS and Arcos satellites. The telemetry reveals that these wolves are often on the move. The 90-pound Brutus and his pack of at least a dozen wolves covered 2,726 kilometers between July 8—the date during the month-long Arctic summer when Brutus was collared—and November 30, within a region of more than 1,900 square kilometers.

In the summer, the wolves are homebodies, taking care of new pups. But this new information helps solve the mystery of what the canine⁵ predators⁶ do to survive the brutal⁷ Arctic winter. Now the question becomes how the wolves know when to stop using the sea ice once the spring thaw⁸ begins.

—David Biello