Some Aspects of the Organization of Fish Schools

The objective of this study was to describe the organization of schools of the pelagic marine fishes Scomber japonicus, Trachurus symmetricus, Engraulis mordax, Atherinopsis californiensis, and Atherinops affinis. Organization was studied in larval through adult stages by analysis of spatial and angular relations among fish in dorsal photographs of schools.In all species, schools of young fish, larval and juveniles, were typically less compact and showed greater differences in angular headings than did schools of adult fish. The rate at which school structure changed with size varied among species; it was rapid in Scomber and the atherinids and slower in Engraulis and Trachurus. School organization differed among species at the adult stage. Schools of Scomber were typically the most compact and organized; Trachurus and Engraulis schools were intermediate in their organization and Atherinops schools were the least organized.Spatial and angular measurements were also used to develop inferences regarding the...