Brettski, not sure about bull frogs, but the frogs here do hibernate. We have three or four different types of frogs and toads too, they burrow down into the muskeg and swamps and survive for at least 7 months. The frost can go down more than three or four feet here, amazing how they survive. I always know when the ground is thawed in spring, the chirping is hard to miss. It's also my wife's "alarm" to start preparing the garden.
