Basically golfing, but on Dolphin back. You play in the middle of the ocean with small platforms set up along a path, the first containing a ball on a tee, the last the hole. You play by holding on to the dolphin's fin with your non-dominant hand, with your club of choice in the other. When the dolphin jumps out of the water, you swing the club and try to hit the ball to the next platform or further(this is easiest at the ark of the jump. Other than that it is similar to golfing.
Hey man, you wanna golfing down at the country club? No way, lets go Dolphing instead.