The Calgary Zoo reopened after a power outage kept it closed on Sunday so handlers could make sure the animals were cared for.

"We had to make that call," said Calgary Zoo spokeswoman Trish Exton-Parder. "It just wasn't a good day to invite our thousands of visitors to come down and enjoy the zoo."

A faulty underground cable is to blame for the power outage. According to zoo officials, the power was restored Sunday evening, although repairs will need to continue over the next few days.

Besides accessing back-up power to keep the animals comfortable, zoo workers took additional steps to make sure the animals are looked after in the heat, she said.

"We ensure they have plenty of shade areas, obviously,... giving them extra water. All the things you would do as a good pet owner. All the things you do to ensure an animal isn't getting dehydrated."