By Linda Weiford, WSU News
PULLMAN, Wash. – Of the hundreds of automobiles that enter the parking lot each week at Washington State University’s Bear Research, Education and Conservation Center, two Toyotas entice the bears like no others.
Similar to children who hear Mom or Dad driving up the driveway, these half-ton predators perk up when researchers Lynne Nelson or Charlie Robbins pull up in their vehicles. Sometimes, like kids on Christmas morning, the bears romp down a grassy hill to stop and wait at the tall chain-link fence until one of the scientists emerges from his or her car.
Not only do these brown furry bruins recognize Nelson’s and Robbins’ respective vehicles, they also seek them out.
“They associate our cars with food because we’re their primary feeders,” said Nelson, a veterinary biologist who has worked at the bear facility on the edge of campus for 12 years. “Brown bears are eating machines, consuming everything from insects, grass and berries to fish and other vertebrates. Anything associated with food – including cars – they’ll remember.”
Targeting imports, minivans
Intriguingly, experts report similar behavior among wild black bears roaming America’s national parks. Car break-ins recorded by park rangers and documented in a scientific study (Journal of Mammalogy, 2009) show that black bears – motivated by hunger and armed with intelligence – have learned to target minivans and Honda and Toyota sedans at parking lots and campsites.
Researchers theorize that this selection process stems from memories related to food. Once a bear scores peanut butter sandwiches inside a minivan with easy-to-pop-out windows, it will seek similar vehicles to raid. Through trial and error, bears have also learned that busting into a small, lightweight Honda or Toyota sedan is simpler than a Cadillac or Hummer.
As if that’s not cunning enough, their break-and-enter techniques rival those used by human car burglars: Pulling down door frames to use as step ladders; yanking off bolted windows; ripping through rear seats to get to the trunk; and pushing and twisting handles and knobs.
Will work for food
Of course, few stories about crafty bears surprise Nelson, including those from California’s Yosemite National Park. Black bear break-ins and lootings got so bad there that officials launched a five-year publicity campaign to discourage visitors from leaving food in their cars and requiring them to use “bear safes” installed at campsites.
The more habituated bears become to human food, the more likely they’ll get aggressive and have to be killed, according to the park’s website.
“Whether captive or in the wild, bears are extremely smart foragers and they’ll work hard to get at food,” said Nelson.
“When a study comes out or we hear news stories highlighting how clever bears are, we just nod our heads and smile,” she said. “We see it here all the time.”
Meanwhile, just on the other side of the fence, a male grizzly rose on its hind legs and gazed downward at Nelson as if listening – or, as she politely pointed out, awaiting his next feeding.
Picking locks
Lead biologist Charlie Robbins founded WSU’s bear center 28 years ago as a way to gain insights into grizzly behavior, nutritional needs, physiology and ecology. The facility houses seven “problem bears” from the wild that otherwise would have been killed and four that were hand-reared as cubs, he said.
America’s largest predators seek him out when he gets to work, just as they do Nelson. Robbins suspects they recognize the sound of his car engine first: “Bears have an acute sense of hearing and smell. Their eyesight, while probably similar to that of humans, is secondary.”
As for their intelligence, “they display a remarkable range of behaviors and skills,” said Robbins. For example, he and Nelson have seen them use a single claw like a key to try to unlock containers.
Smartest of them all?
The facility’s 9-year-old grizzly, named Peeka, earns top place for demonstrating the most systematic ability to foil human security efforts. On her own, she learned a three-step process enabling her to slide open a door leading to an enclosed pen. Using her massive paw, she undid a spring-loaded clip; lifted a latch; then slid a bolt.
“Whenever I’d hear the clip hit the floor, I knew I had about two seconds to vacate the pen before the door would swing open,” recalled Robbins, who tried a more sophisticated type of latch. But Peeka figured that one out as well.
“It took her about 15 seconds to open the latch, remove it, throw the bolt, step into the pen and ‘Hi, here I am,’” said Robbins. “I decided there wasn’t any type of spring latch that she couldn’t open.
“So now we put a lock on the door,” he said. “Period.”
Contacts:
Lynne Nelson, WSU bear center, 509-335-0711, olnelson@vetmed.wsu.edu
Charlie Robbins, WSU bear center, 509-335-1119, ctrobbins@wsu.edu
Linda Weiford, WSU News, 509-335-7209, linda.weiford@wsu.edu