Grizzly at Minn. Zoo shatters glass pane with rock

MINNEAPOLIS - Minnesota Zoo-goers were in for a surprise when a grizzly bear repeatedly slammed a 50-pound rock into the glass wall of its enclosure, cracking the thick pane, CBS Minnesota WCCO reports.

Director of Animal Collections Tony Fisher told WCCO that the custom-made laminated safety glass did what it's supposed to do -- only one of its five layers shattered. The glass is 2.5-inches thick.

"A brown bear weighs 800 or 900 pounds, so it's not much to them," Fisher said.

Fisher said the bears must have loosened one of the rocks in their enclosure and then used it to slam the window. Three grizzlies live in the enclosure, but zoo staff told WCCO they are not sure which one was responsible for the glass shattering. They think it was probably the middle-sized brown bear, Kenai.

On its website the Minnesota Zoo writes that Kenai likes to swim and fish and that his distinguished characteristics are that he is the most submissive of the group. He is known to be curious, but shy.

He regularly wrestles with the other grizzlies, and when it comes to new things, "he's most likely to be the first to try them."

Fisher told WCCO the bears weren't being aggressive or trying to escape the enclosure when the shattering occurred, they were just playing. He added that nothing like this has happened since the orphaned bears arrived at the zoo from Alaska in 2008.

"Everything else in this exhibit is pretty much concrete and steel, pretty indestructible," Fisher said. "We designed this exhibit to withstand the bears, and what they can do."

The bears have been removed from their exhibit and won't be back for a few days until a replacement pane can be installed.