Physics and physiology of fish collective movement

Abstract

The collective movement of animals has long been of interest to mathematicians, physicists, engineers, and biologists. This includes understanding the emergence of group motion from individual interactions, hydrodynamics of group locomotion, and biological processes that generate movement. Here, we discuss recent research on fish schools to understand how group movement alters hydrodynamics, energy use, and inter-individual interactions. Swimming in a school can save metabolic energy up to 56%–79% at higher swimming speeds when compared to swimming alone, and a clear minimum in the cost of transport exists at speeds around two body lengths per second, which is similar to swimming alone. We discuss that energetic savings result from a diversity of hydrodynamic mechanisms that are constantly changing as fish rearrange themselves within a school. A key goal of future research is to reveal potential global mechanisms of energetic savings in fish collective movement.

Topics & Concepts