Density-dependent attributes of schooling in small pelagic fishes.

Many small pelagic fishes obligately form schools; some of these schools reach remarkable sizes. Although the school is a fundamental and important ecological unit and is the site of biological interactions such as competition and predation, information on schooling processes in the field remains scarce. Here, we examined the quantitative relationships between population density and school size, the number of schools, and other school characteristics (i.