PRAGUE (AP) — Keepers at Prague Zoo used tons of ice on Thursday to give its animals some much-needed relief as yet another heat wave hit Europe.

Polar bears Aleut and Gregor wasted no time and were rolling in the beds of ice cubes after entering their outside enclosure.

The twins looked to have fun with the ice treat that was meant to keep them cool amid the extreme temperatures forecast to soar to 38 degrees Celsius (100.4 degrees Fahrenheit) later in the day.

“The bears cool off with it and at the same time it’s an enrichment of their life in the zoo,” said zoo spokesperson Filip Mašek.

The zoo began providing ice to some of the animals two years ago in response to climate change and the increasing number of days with extreme temperatures.

The polar bears, who were born in Nuremberg, Germany, 16 years ago and have adapted to the European climate, were the ones who enjoyed it the most.

This year, the plan was to order ice for the animals in July and August, which are traditionally the hottest months. But the first heat wave struck early and the Czech Republic experienced its hottest day ever with 41.9 C (107.4 F) on June 28.

“The weather keeps surprising us,” Mašek said. He said the ice will be ready sooner next year. “We’ve been taught a lesson.”

Other animals that have benefited from the provision of ice to keep cool in previous years include otters, elephants and parrots.

Some animals in the zoo are used to heat, others could stay in the shade or inner enclosures and use various pools to keep cool. Gorillas were given pieces of ice with frozen fruits in the previous years.