One of the three Grizzly Bears at the Minnesota Zoo decided it would be a good idea to throw a 50 pound rock at one of the windows of the viewing area to their exhibit, and he left quite an impression in the glass, and to visitors alike.

The bears were quickly escorted to an inside pen used for feeding and sleeping at at no point were any zoo visitors or staff in danger. The glass is reinforced with 5 layers and the rock just damaged one of the 5. The average brown bear weighs between 800 and 900 pounds so tossing a rock of that size is no big deal.

The director of Animal Collections said that the bears were not trying to escape they were just playing and somehow this rock got loose. They are not sure exactly who threw the rock, but they suspect it was the medium size bear Kenai. Maybe Goldilocks can try and figure it out for them?

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