Other mistake: A letter from Popper's father falls unnoticed beneath a cabinet. For several days the room is covered with snow to accommodate the penguins. After the snow is removed, Popper discovers the letter but the envelope is not damp, waterlogged or damaged in any way.
Continuity mistake: At the Guggenheim Museum, the penguins bump into a man pushing a barrel of ice and the barrel overturns. The penguins immediately begin sliding on the wet floor, but all the ice has vanished and instead there is only water on the floor. In addition, the water covers several hundred feet of the floor, far more than what a barrelful would cover.