Hanna, director emeritus of Ohio's Columbus Zoo and Aquarium, gave an inside look at the dramatic enclosure, which features solid glass walls that give visitors an extremely close view of the bears.
Hanna called the zoo's enclosure the best habitat in the world.
The polar bear habitat features a 1.32-acre yard with two pools including a brackish water still pool that is 167,000 gallons. The water will be kept between 55 and 65 degrees year-round due to underground geothermal tanks. The habitat offers viewing of the bears from above, at eye-level, and below beneath four feet of water. The windows are 5" thick acrylic.
When inside the glass-walled aquarium level where visitors can see the bears at close range, one of the bears swam at eye-level with Hanna and then kicked off the aquarium's glass wall.
Hanna joked, "I hope that glass holds!"
For more with Hanna and the bears and some of the other animals featured on "The Early Show," click on the video below.
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