A Simulation Study on the Schooling Mechanism in Fish

Abstract

A computer simulation was performed to examine the schooling mechanism. The model uses the basic assumptions that the speed and direction of individual movements are stochastic variables, and that the direction of movement is related to the location and heading of the neighbors. Three behavioral interactions between individuals were considered; approach, avoidance, and parallel orientation movements. Individual movements and the resultant group movement were simulated by repeatedly generating random numbers. It was found that group movements in unity could occur despite each individual lacking knowledge of movement of the entire school, and in the absence of a consistent leader. The results lead to the following conclusions: for effective schooling to occur, individuals must possess two types of behavior; 1. approach movement to allow aggregation, and 2. parallel orientation movement to allow the group to move cohesively. Experiments were also performed with varied combinations of model parameters, and a wide variation in the movement pattern of the simulated school was obtained. © 1982, The Japanese Society of Fisheries Science. All rights reserved.