It is illegal to own a Ferret in California, because Ferrets are wild animals. Many times these animals have been used to lower the amount of rabbits in the area. They can become a threat if there are too many of them running wild. It is believe that if ferrets are let out into the wild, they would mate, multiply, become feral and could threaten native wildlife. As of the year 2000, ferrets are legal in 48 states. However, California and Hawaii have declared ferrets illegal in the entire state.