Most fisheries select the size of fish to be caught (are size selective), and many factors, including gear, market
demands, species distributions, fishery laws, and the behavior of both fishermen and fish, can contribute to that selectivity. Most fishing gear is size-selective and some, such as gill nets, are more so than others. The targeting behavior of fishermen is another key reason commercial
and recreational fisheries tend to be size-selective. The more successful fishermen constantly seek areas and
methods that yield larger or more profitable sizes of fish. Fishery regulations, especially size limits, produce
size-selective harvests. Another factor with the potential to cause selectivity in a hook-and-line fishery is the different behavioral responses of fish to the bait or lure, whether the different responses arise among different fish
sizes or between the sexes
