When the San Diego Zoo got a call asking if they could train a polar bear to walk on a treadmill, as Megan Owen remembers it, their first reaction was: Sure!
Owen is a biologist at the zoo, and her colleagues there regularly train polar bears in, let’s say, un-polar-bear-esque tasks. Their bears have learned to reach out their paws out for voluntary blood draws. One female polar bear, Chinook, learned to lie still for ultrasounds. She was even part of a polar-bear hearing study in 2006, where she learned to press her nose on a pad when she heard a sound. “Polar bears are incredibly intelligent animals,” says Owen. It just takes patience and many, many buckets of raw meat and fish.
The call about treadmills came from Anthony Pagano, a biologist with the U.S. Geological Survey who wanted to study how polar bears walk. Once he convinced two zoos to get on board—in San Diego and Oregon—Pagano had the polar bears. But he still needed a treadmill. He knew colleagues who had put other large mammals, like mountain lions, on treadmills before. “But nothing as destructive as polar bears,” he says. Nothing as a destructive, in other words, as a 500-pound colossus that could take out a human with a swipe of its paw.
Pagano’s team ended up buying a two-ton, 10-foot treadmill designed for racehorses. Then they brought it to the machine shop at Washington State University, which custom-built a bear-proof chamber of polycarbonate and steel. The enclosed chamber over the treadmill also allows researchers to sample the amount of air inside. As the bear walks, it starts using up some of the oxygen, giving scientists a sense of how much effort it is exerting.
Down in San Diego, the keepers decided that Tatqiq, a then-16-year-old female, would be the lucky bear. At first, Tatqiq’s keepers let her into the chamber with the treadmill off. She would lay or stand in there for a few minutes at a time and collect her food reward. Several weeks later, they turned the treadmill on at the slowest setting. “Of course the floor moves and that changes everything,” says Owen. Tatqiq headed for the exit.
But eventually, she was lured back with the promise of more food. Her trainers gradually turned the treadmill to higher speeds, still feeding her a scrap of meat or fish every 20 …read more
Source:: The Atlantic – Science