Off the rugged coasts of Western Australia, marine biologists have documented a striking defense by sperm whales against predatory killer whales. The whales release large fecal bubbles, forming a dense curtain of excrement that disrupts the chase and gives the pod a chance to break contact. This defensive tactic has been reported by ABC News Australia and is now recognized as a behavioral adaptation in the region.
Researchers describe the behavior as defensive defecation, a rare response that first drew astonishment. Initially, observers suspected the dark plume in the water came from blood, but further analysis confirmed it was feces. The squid-based diet of this whale species lends a reddish tint to its waste, making the phenomenon visually striking as bubbles rise and disperse through the water column.
Biologists observed that the strategy involves more than simply ejecting material. Sperm whales actively direct the fecal clouds toward approaching orcas by maneuvering with tail blows, creating a noxious, turbid barrier that hampers the predators and reduces sensory clarity for their pursuers.
The tactic appears to be effective in several encounters, with orcas retreating to seek cleaner water as the cloudy plume interferes with their sense of sight and possibly scent. The outcome can be decisive, allowing the larger whales to reassess the threat and maintain distance from the threat to their group.
Experts note that the size difference between the species matters. Sperm whales can reach around 20 meters in length and weigh up to about 50 tons, while killer whales generally measure 6 to 8 meters and weigh roughly 2 to 10 tons. This disparity often shapes the dynamics of these interactions and influences the strategies each side employs in the encounter.
In a separate note from the same regional waters, observers reported a great white shark incident near New Zealand involving a pygmy sperm whale. The event drew attention to the diverse range of marine predators that encountercetaceans, though it remains a relatively rare occurrence and is handled carefully by researchers and onlookers alike.