Some Field Measurements on Minnow Schools

A field technique is described for examining schools of fish by recording their times of capture during electrofishing. The technique is suitable for streams and rivers where the fish can be seen as they are caught. Analysis of the time intervals between minnow captures was carried out by fitting a mixture of gamma and exponential distributions. The results show that clusters of minnows were encountered at random during fishing. The clusters are considered equivalent to the schools in which minnows live in the wild, but the inadequacies of verbal recording preclude any biologically meaningful analysis of the within-cluster distributions.