They are Asian carp. They swim around in circles about 6 feet in diameter slightly below the surface with their mouths wide open filtering out the small insects that are slowly sinking. My pic shows all the small insects on the surface that have not begun to sink yet. They are like vacuum cleaners in their enviroment. I could spear every one at my dock and it wouldn't make any difference. I have seen schools in some of the bays on this lake at had probably a 1000 carp in them cruising just below the surface . This was five years ago. Far worse now. Man created this problem but I don't think man will solve it.