The term ‘bycatch’ is used to describe the non-targeted species caught while targeting the more desirable species when fishing. Different fishing methods result in differing amounts of bycatch, for example, bottom trawling has higher rates of bycatch than longlining.
In commercial fishing, bycatch can be species caught that the fisher is not allowed to keep, does not want, or cannot sell. Marine mammals and seabirds are also classed as bycatch due to fishing.