Saw a thing on National Geographic the other night about all the pythons and other constrictors that people buy as pets in Florida that get loose. Apparently some of them have been turning up in the Everglades and there are fears they will greatly alter the ecosysystem there. They even documented how one of them got big enough to eat a six foot gator. It may be more enviropropaganda but I tend to think they weren't exaggerating too much, and it was really chilling when one of the people they interviewed said, "If one of these things can eat a sic foot gator, you can bet they can eat a human child with no trouble, and that will sure get people's attention."
It's true. People let snakes and reptiles loose when they get too big. THey say the everglades is overpopulating with Pythons. Stupid people.