Growing up in the SE these were everyday sights. They almost never go after humans; just don't take fido for a walk nearby or problems ensue. When I first moved to the SE we went on a float trip down the ichetucknee. As a kid I was ready to run on water the first time I floated 10 ft past one sunning itself; everyone assured us it was fine though. They do teach all kids in school to run in a zig zag and try to get up a tree if they chase you, they can't turn while moving and have to come to a complete stop to turn.