Even though these sperm whales are 500 m apart, their actions are concerted and their movements are synchronous.

An individual which dive collects information about the bottom and the prey on it by the echo of the sound it emits. These same signals could be heard by the neighbours of his Alliance*, who are listening in the same direction. The partners also emit a sound, which gives additional information to what the first individual is hearing. It is a real-time exchange. It is also conceivable that they transmit signals to each other describing what they perceive. They could derive a benefit from this, in the quality of their perception of their environment: all the echoes of the sounds emitted by the members of the Alliance would go beyond each individual perception.

We can see, on the 3D representations developed by Pr. Hervé Glotin’s team, that following these Alliances, some sperm whales follow deeper trajectories towards -1700 m off the coast of Monaco. Then they sweep a large volume of water, and probably capture several squids.

* The Alliance is a cooperative bond that persists over time between the allies. It’s a pattern known among top predators such as lions and wolves. The most studied case of Alliance among cetaceans are pairs or triplets of bottlenose dolphins (Tursiops Truncatus) that cooperate for different tasks. An Alliance is often between individuals of the same family.

In the case of sperm whales, no hunting Alliance has ever been observed.