Have had jet skis buzz me when fishing for late winter natives on the Sky, in march when the day temp only reached the upper 40s. Two jet skis thrashing the water where I was fly fishing just ruined my day. And again last week, had one jet ski attempt to buzz the drift below me untill he saw the drift fishermen, then he beat a hasty retreat. Jet skis have been banned in and around the San Jaun Islands, dont see why they couldnt be banned on rivers also.