Staying cool at the zoo

Hudson the polar bear gets a treat of fruit served on a block of ice to help him keep cool in his enclosure at Brookfield Zoo in Brookfield, Ill., July 18, 2013.

A heat wave continues to grip much of the country today with temperatures expected to top 90 degrees in 47 states.

Visitors watch as a grizzly bear cools down in the pool in his enclosure at Brookfield Zoo, July 18, 2013.

Hudson, a polar bear, cools down by playing with a block of ice during a swim in his enclosure at Brookfield Zoo, July 18, 2013.

A sloth bear cub gets a treat of fruit served on a block of ice to help him stay cool in his enclosure at Brookfield Zoo, July 18, 2013.

A lion gets a treat of meat frozen into a block of ice to help him stay cool in his enclosure at Brookfield Zoo, July 18, 2013.

Grizzly bears cool down in their enclosure at Brookfield Zoo, July 18, 2013.

Hudson, a polar bear, cools down by playing with a block of ice during a swim in his enclosure at Brookfield Zoo, July 18, 2013.

Hudson, a polar bear, cools down with a swim in his enclosure at Brookfield Zoo, July 18, 2013.

A grizzly bear gets a treat of fruit served on a block of ice to help him stay cool in his enclosure at Brookfield Zoo, July 18, 2013.

A sloth bear cub gets a treat of fruit served on a block of ice to help him stay cool in his enclosure at Brookfield Zoo, July 18, 2013.

A grizzly bear cools down with a swim in his enclosure at Brookfield Zoo, July 18, 2013.

Polar bears get a treat of fruit served on a block of ice to help them stay cool in their enclosure at Brookfield Zoo, July 18, 2013.

A grizzly bear gets a treat of fruit served on a block of ice to help him stay cool in his enclosure at Brookfield Zoo, July 18, 2013.

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