Bylaw officials in Calgary say they are seeing a large number of dogs left in hot vehicles this summer. (Heidi Grzesina)

Calgary bylaw officers have had to rescue an unusually large number of animals from hot cars this month.

The city’s 311 line has received more than 60 complaints from people who have seen dogs locked in sweltering vehicles, said Andrew Bisset, who speaks for Calgary Animal and Bylaw Services.

That's about four rescues per day, he added.

“You do have to have to think, especially when the temperatures are hot or cold, on how long you're going to be in one place,” Bisset said.

The basic fine for leaving an animal in a hot car is $100, but the issue can be sent to court where the penalty can spike to $10,000.

Four of the incidents this month led to neglect charges.