I see them along the banks and near shore of the Intracoastal from time to time in the early AM hours when I'm walking my German Shepard (100 lbs), she wants nothing to do with them.....
Let me tell you this, we vacate the area pronto. I have never seen a seemingly large "sluggish" animal move as quickly as they do. Sometimes the light from my flashlight startles them and they seemingly do a 180 back flip in midair to get back in the water so quickly I can't believe what I saw ! It's a blur.
Later on the day I'll walk back to the park and see parents letting their kids swim in that same spot. I'm always walk over and tell them their taking a chance, most listen.
Ron W.