Whale Surfacing Behaviour - Peduncle Throw

In a peduncle throw, the humpback converts its forward momentum into a crack-the-whip rotation, pivoting with its pectorals as it drives its head downward and thrusts its entire fluke and peduncle (the muscular rear portion of the torso) out of the water and sideways, before crashing into the water with terrific force.

Usually peduncling takes place among the focal animals (female, escort, challenging male) in a competitive group, apparently as an aggressive gesture. Possibilities include escorts fending off a particular challenging male, females who seem agitated with an escort, or an individual not comfortable with a watching boat's presence. Occasionally, one whale performs a series of dozens of peduncle throws, directed at the same target each time.