06/14/2011 at 04:00 PM EDT
One of the biggest challenges of working with a bunch of penguins is – well, you might call it cold feet.
The new movie Mr. Popper's Penguins, starring Jim Carrey and Carla Gugino, features the work of eight live penguins (in addition to some CGI penguins), and to accommodate the subarctic creatures, the film set had to be kept between 45 and 50 degrees Fahrenheit – at all times.
"Basically, the set was so cold that I was fighting pneumonia the entire time," Carrey said at a press conference for the film. "I don't even think it's really about the health of the penguins. It's cause they're method [actors]. That's what I found out."
"It was sort of selfish on their part," Gugino remarked.
The humans were the ones dealing with below-50 temps, but the penguin "trailer," so to speak, was even colder. The penguins' trainer, Larry Madrid, set up a walk-in freezer for the birds, who chilled out at a comfortable 33 degrees.
In addition to their exacting climate requirements, the birds – known by such names as What Can Brown Do For You, and Richard Dent – were a little aggressive about biting their co-stars.
"My ears were much bigger at the beginning of the movie," Carrey said at the movie's L.A. premiere. Carrey's co-star, Clark Gregg, had a similar experience. "They'd nip your fingers every once in a while, if you don't get rid of the fish in time," he said. "But I actually really enjoyed them."
"The penguins are awesome," Carrey said. "You can't deny them. They're actually my favorite animal, and that's why I did the movie in the first place. I don't think anybody can be unhappy around a penguin."