Am I the only one who finds this flippant attitude regarding the disappearance and, most likely, the DEATH of his turtles disturbing?
Up until this thread, I'd been impressed by the level of knowledge and compassion displayed on the forum- it seems as though people took the time to become knowledgeable about the species they maintained.
If you intend to keep the turtle, then yes. You need a fence. At this rate, however, I'm voting that you rehome the turtle and remain chelonian-free.