Polar bears have made their return to the Columbus Zoo and Aquarium after an absence of more than 20 years.

Polar bears have made their return to the Columbus Zoo and Aquarium after an absence of more than 20 years.

Twin females, Aurora and Anana, arrived at the zoo Feb. 19 to little fanfare. Their $20-million Polar Frontier exhibit is scheduled to open this spring, although an opening date hasn't been set.

"There's still work being done outdoors and of course the weather is not helping at all," said Patty Peters, the zoo's community relations director. "We don't have an opening date yet for Polar Frontier."

The polar bears were transported to Columbus from the Pittsburgh Zoo, where they have lived since 2008. The twins were born at the Toledo Zoo in 2006.

"The residents of central Ohio spoke and we listened," zoo executive director Dale Schmidt said in a news release. "It's been more than 20 years since polar bears were at the Columbus Zoo and they are back by popular demand. We can't wait to share Polar Frontier with the community."

The polar bears will remain inside their habitat until their 1.32-acre exhibit opens. Aurora and Anana will have two pools, one of which will give visitors the ability to watch the polar bears from above, at eye-level and below. The other pool is a surge pool that will move water with a tidal effect.

Peters said "smell pits" within the living area will give the polar bears something "out of the ordinary."

"In the wild they would hunt for seals by smelling for seals through holes in the ice," she said. "We tried to recreate that by putting different smells in holes in the habitat. We do a lot of enrichment with our animals. With our wolves, we spray bedding down with perfume or spices, any number of things to get them interested, digging and rolling around. It just gives them something out of the ordinary."

Polar bears are accustomed to subzero temperatures; in January, for example, the average temperature in the Arctic is 29 degrees below zero. But they won't have many problems with central Ohio's warm summers.

"As long as it's not extreme weather, they're fine," Peters said. "They do have polar bears at the zoos in Toledo and Cleveland. As long as they're not in a desert setting and they have water, they're fine."

The Polar Frontier exhibit also will house another new animal, an arctic fox, and the Battelle Ice Bear Outpost, which will provide visitors information on climate change and how to practice conservation. The exhibit also will give children a place to play on a polar-themed playground.