Flameethrower is right, Bulls, Gophers and Pine snakes are not rear fanged, just a big constrictor. Care is very much like a cornsnake. Which breeder did you get them from? My Pine hissed and vibrated her tail a lot the first few weeks I had her. It's rarely happens now. They are opening their mouths when hissing to expel air over their epiglottis, a special membrane they developed for hissing loudly as a defensive mechanism.