The sight of a whale propelling its massive body out of the ocean and crashing back down with a thunderous splash is one of nature’s most dramatic displays. This awe-inspiring behavior, known as breaching, involves a whale launching itself partially or fully into the air. While captivating to witness, the precise reasons behind this powerful aquatic acrobatics remain a subject of ongoing scientific inquiry.
Not All Whales Breach Equally
While many species of whales are known to breach, this behavior is not uniform across all individuals or types of whales. Humpback whales, for instance, are among the most frequent breachers, often performing this display multiple times in a series. Other species commonly observed breaching include right whales, sperm whales (particularly females), and oceanic dolphins like orcas, which can even clear the water entirely.
Conversely, some of the largest whale species, such as blue whales and sei whales, rarely breach, and fin whales do so infrequently. The size of the whale plays a role, as larger whales must expend significantly more energy to launch themselves. Even within species, breaching frequency can vary, with some individual humpbacks breaching dozens of times in a short period.
Why Whales Perform This Leaping Act
Scientists propose several theories for breaching, suggesting that multiple factors may be at play depending on the situation. One prominent idea centers on communication. The immense splash and sound generated by a breach can travel considerable distances underwater, potentially signaling to other whales about social status, warning of predators, or indicating mating readiness. In noisy ocean conditions, breaching might be a more effective way to communicate than vocalizations, which can be harder to hear.
Another hypothesis suggests that breaching helps whales dislodge external parasites, such as barnacles and whale lice, that attach to their skin. The forceful impact with the water could effectively scrape off these irritants. Breaching may also serve as a form of play, particularly among younger whales, helping them develop physical coordination and strength.
Beyond these, breaching could be a territorial display, asserting dominance or sending a clear message to other whales or potential threats. Some researchers also propose it aids in navigation, allowing whales to gain a brief aerial view of their surroundings, which could be useful in busy coastal areas. The loud impact of a breach might also stun or disorient prey, making them easier to catch.
Breaching Versus Other Water Displays
A true breach is an intentional leap where 40% or more of the whale’s body clears the water. Whales often clear a significant portion of their body, with some humpbacks achieving over 70% emergence. This differs from a “lunge,” which involves less than 40% body clearance and is an unintentional result of fast, upward swimming, particularly during feeding. While breaching is a deliberate action to clear the water, lunging is more about pursuing prey near the surface.
Breaching is an energetically demanding activity. The energy expended by a large humpback whale for a single breach can be comparable to that of a human running a marathon. Despite this energy cost, whales frequently perform multiple breaches in a series, sometimes over a hundred leaps in a short period. This ability to expend such energy may also signal fitness to other whales.