Surf the Wake: How do fish swim in schools without colliding?

Fish are able to move in groups, without separating or colliding, due to a newly discovered dynamic: the followers interact with the wake left behind by the leaders. The finding offers new insights into animal locomotion and points to potential ways to harness energy from natural resources, such as rivers or wind.

“Air or water flows naturally generated during flight or swimming can prevent collisions and separations, allowing even individuals with different flapping motions to travel together,” explains Joel Newbolt, a doctoral candidate in New York University’s Department of Physics and the lead author of the research, which appears in the Proceedings of the National Academy of Sciences. “Notably, this phenomenon allows slower followers to keep up with faster-flapping leaders by surfing on their wake.”