The Effects of Changing Geometry on Fish Motion in Shoals

Fish within schools exhibit intriguing collective behaviors. These collectives can be considered assemblies of active interacting constituents within an amorphous material. The fish propel themselves while simultaneously processing information about their environment. We view shoals as assemblies of active particles-- This perspective allows us to categorize the movement of individual fish and see in what ways they differ from assemblies of passive particles. We investigate the dynamics of individual fish moving by recording videos of fish swimming within the lab in quasi-2D volumes of water. We identify and track fish positions, trajectories, and velocities over time for each fish within the collective. We observe that by controlling the group size and system density, we can control fish motion and speed.