Regarding the Alligators mentioned in the article at Shell Island, TX anchorage, we stayed there about 5 years ago. I dinghied Coco, our Dachsie, into the beach for a walk, when I looked at the water a gator was eyeing him up for an evening snack. if you look closely at the picture which my wife took from the boat you will might see the top of the gators head and ripples in the water just out from and to the right of the dinghy. I slapped the water with an oar a couple of times and he went under, didn't see him again.
needless to say no swimming for me there either