Pectoral Slapping
Channel: Sean Anderson
Date: 02/02/2024

For views on a different day, see here: https://youtu.be/r8WcbP7YLCM?si=ysXVYQ2Vl1OjXVpd


These two humpback whales were in the Maui Channel in mid-January of 2024.

Humpback whale pectoral slapping is a behavior observed in these majestic marine mammals, and while its precise function is not entirely understood, researchers suggest several potential explanations. Humpback whales (Megaptera novaeangliae) are known for their acrobatic displays, and pectoral slapping involves the repeated striking of one or both large pectoral fins on the water's surface. Possibilities include:

Communication: Pectoral slapping may serve as a form of communication among humpback whales. The loud sound produced during slapping can travel over long distances underwater. Whales in the vicinity may use these sounds to communicate with each other, potentially for mating purposes or social interactions.

Social Interaction: Pectoral slapping is often observed in groups of humpback whales, suggesting that it could be a social behavior. It may be a way for individuals to signal their presence, coordinate movements within a group, or establish social hierarchies.

Agitation or Distress: In certain situations, humpback whales may slap their pectoral fins when agitated or distressed. This behavior might be a response to perceived threats or disturbances, such as the presence of vessels, predators, or other stressors in their environment.

Playful Behavior: Like many mammals, humpback whales are known for engaging in play. Pectoral slapping could simply be fun and a form of play, allowing them to interact with their environment in a joyful and acrobatic manner. This behavior is often seen in calves, suggesting that it might be a learned behavior through playful activities.