I've shot alot of fish the size of footballs to the size of pop bottle at less than 5 yards moving just as fast or faster. Its all instinctive shooting exspecially when its that close. Weather or not its ethical is based on the shooters ability. I've had people in the boat with me that can't beleive I hit such a small target moving and say I got lucky but hten I do it again after they miss one and they can't beleive it. I tell em its all about practice sure I miss some but thats a small target to hit sitting still let alone moving fast. Sometimes I even suprise myself with hitting some but if you do it enough it just comes natural. I would take those shots that close but anything further no way unless they are walking or stopped. Good shooting. WCL