Being that cross-breeds can be enormous, it could be plausible. Might also explain the lack of fear of humans that most wild animals usually have.

I remember seeing commercials for that movie. To be honest, I don't really enjoy movies like that. I'm more interested in the animal side of the story than to watch humans freak out for an hour and a half while they wonder what is going on, and how they're to deal with it. (Plus, I prefer D&D werewolves to real world accounts. I'm so boring! ;) )