My wife and I were about 2 miles off the Gulf Coast near Sarasota in a Sunfish Sailboat. It was light air and water visibility from the Sunfish was good. We were closely examined by a really large shark...in the 12-14 ft size range...probably a bull. As you know, a Sunfish only has about 8" of freeboard so we were really there with him. I pulled out the daggerboard and was prepared to bring it down on his nose if there was any aggressiveness. He kept a serpantine movement as he examined the Sunfish from stem to stern...spending a little quality time with me and the daggerboard and then was gone.
There is a lot of curiosity from sharks. The rule of thumb from experts at Mote Marine when I relayed the story was...if you can see headlights on the road, don''t be in the water. This is feeding time. Also don''t be in the water fishing with bait boxes.
Also I heard...don''t be splahing a lot when swimming as it can cause cunfusion down there.