Also called lobtailing, fluke slaps are usually seen when the Humpback Whale (Megaptera novaeangliae) is in a normal dorsal (backsideup) posture with the flexible peduncle, lifting repeatedly out of the water and slapping the water with the ventral side of the fluke.
Sometimes, however, this may involve a headdown posture of the whale and back and forth action alternately slapping both ventral and dorsal surfaces of the fluke.
