Beating Polar Bear Boredom

(AP)  Gus repeatedly swam figure-eight laps in his pool. Marty paced the same path over and over, carefully putting his paws in the same place each time. Zoologists say such behaviors displayed by captive polar bears are signs of boredom and stress.

Keepers at the Toledo Zoo, where Marty lives, hope their new $11.5 million Arctic Encounters exhibit will give Marty and his fellow bears more things to do and make for happy, well adjusted animals.

The exhibit, which opened this month, features a fresh water stream where the bears can catch fish themselves and a dirt pit where they can dig for food.

"Polar bears are fairly nomadic in the wild," says Tim French, the zoo's mammals curator. "Here we take care of everything so they've got too much time on their hands."

The polar bears can now splash around in four 300,000-gallon pools. By comparison, the old polar bear home was a small concrete pit with one just 10,000-gallon pool.

However, animal rights supporters doubt, no matter how lush the new habitat, the new four-acre enclosure can never duplicate the expanse of the Arctic.

"Underneath all of the trappings, it's still a concrete box," says Naomi Rose, of the Humane Society of the United States. "There are certain animals that are too large, too social and too intelligent to be held captive."

In the wild, polar bears cover 50 miles a day and their lives center on roaming and the search for food, primarily seals.

They are also extremely intelligent animals.

For instance 3-year-old Marty would balk when it was time to go inside for the night. He would use his body to block the door and also placed a small ball on the door's sliding track, preventing the keepers from closing it.

This intelligence has researchers at a dozen zoos across the nation studying polar bear stress. They suspect that the reason captive polar bears show signs of stress more frequently than other animals is primarily because they are so smart.

But what triggers their repetitive, almost compulsive behavior is still a mystery. A study being conducted at the Oregon Zoo in Portland examines whether captive polar bears have an increase in stress hormones that trigger repetitive behavior.

One of the most famous cases of bear boredom was recorded in 1994 at New York's Central Park Zoo, where the polar bear Gus swam obsessively in his pool.

On the advice of animal behaviorists, the zoo created games for Gus which would cut into his swimming time. During the holidays, keepers gave him big boxes of toys and food to unwrap.

Other zoos have also had some success with new exhibits geared toward entertaining and occupying the animals. Polar bears at the San Diego Zoo pace much less since moving into a bigger, more interactive enclosure three years ago.

The new Toledo exhibit also allows the bears to look through a glass-bottom floor and watch the seals swim by. French says, "We didn't want to build a concrete cage and swimming pool, we wanted to build an area the animal could explore."

The drawback is that maintaining such elaborate enclosures is expensive and time consuming.

Researcher will keep an eye on Marty, and babies Mizar and Alcor to develop a behavioral profile and determine what stimulates the bears.

"What seems to work best is changing the polar bear's daily routine and giving it new things to explore," says Bob Wilson, president of Polar Bears Alive.

The nonprofit organization, which works for the protection of the polar bear and its habitat worldwide, says zoos are improving polar bear care but, "It's always going to be a battle to make their lives barely tolerable."