Study: Some Fish Thrive in Unorganized Conditions

A new study found that some fish in shoals, or large numbers of fish swimming together, forage for food better when the group is disorganized. Researchers from the University of Bristol observed 12 groups of fish for a month. They determined the speed at which individual fish in shoals located food that suddenly and sporadically appeared in their environment. The groups were examined several times so that the scientists could determine how individual fish performed under both orderly and disorderly shoal conditions. Results showed that the fastest fish to find food were those that tended to swim less aligned with the majority of other orderly fish in the shoal. These disorderly fish swam in a manner where they could respond faster than others when food was available. The team said that a disorderly condition was favorable for these fish because they were not constrained to look in the same direction as the rest of the shoal. The disorder gave them a better line of sight. According to the researchers, while an organized shoal may be beneficial for many fish, order may not always be a good thing for those that are good at foraging food on their own. The researchers added that the study calls for further investigation of the dynamics involved in group animal behavior and the significance of individual differences among animals.