Not sure about Florida, but snakes, even poisonous ones, are protected here in TN. Not supposed to kill them. If it is causing a nuisance, you are supposed to call wildlife agency, etc. to relocate it.
Cottonmouth Moccasin test: if the snake swims with its entire body on top of the water, it's a cottonmouth; if only the head or front 1/3 of the body is above water, just a common water snake.
Last summer I saw a HUGE cottonmouth swimming in the lake behind Stinky's. They don't grow them that big in TN!
However, there is one bad-ass snake up here that makes all others look like wimps: they're called lawyers.