SSS 2010-01-07(在线收听

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 Celsius. Enough to give nightmares to musk ox and Arctic hares, the favorite prey 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 jaunts 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 canine predators do to survive the brutal Arctic winter. Now the question becomes how the wolves know when to stop using the sea ice once the spring thaw begins.


—David Biello
 

  原文地址:http://www.tingroom.com/lesson/sasss/2010/1/99223.html