One of the grizzly bears at the zoo in Apple Valley, Minnesota, broke one of the five layers of the floor-to-ceiling observation glass by repeatedly slamming it with a basketball sized rock Monday. the Star Tribune reports.
The zoo has temporarily closed the exhibit, which houses three grizzlies that were orphaned in Alaska, until the broken panel can be fixed and made more secure. As a replacement, a permanent and custom-made pane will be installed at a cost of tens of thousands of dollars.
Members of the zoo said that they thought they had taken all of the rocks out of the exhibit, but that one of the bears must have dug one up.
In addition to a new window installation in the wake of the incident, staffers will have to go back through the exhibit and “anchor down anything they can lift,” the zoo animal collections manager, Tony Fisher said, according to the Tribune.
No creatures on either side of the panes were harmed, according to Fisher.
Robin Ficker, a visitor from Maryland, recounts his experience as a first-hand witness, saying the rock had to weigh at least 50 pounds. The 800-pound grizzly pounded the glass until it appeared to crack.
Although it remains unknown which bear was responsible, Fisher pointed to Kenai as the culprit, seemingly for his clown-like distinction among the three animals.
“He didn’t know what he was doing,” he said. “He was just being a bear.”
The incident might seem like a scene from Werner Herzog’s, “Grizzly Man,” but zookeepers claim that the bears are not a danger to the public, as their purported aggressiveness is only in playful spirit. (RELATED: Wild Animals GONE WILD As Bear Kills Rutgers Student, Fox Attacks Four At Conn. Grade School)