EXPLOITATiON OF FISH POPULATIONS

The tcrm "exploitation" implies the idea of making use of the population, and in fisheries is generally regarded as a process which should be continued indefinitely without destroying the population. Very intense exploitation leading to the complete destruction of the population, or at least its reduction to a level so low that further exploitation is not worthwhile, is rarely, if ever, deliberately practised in dealing with fish populations although it may sometimes occur unintentionally and as a result of mismanagement. In New Zealand the pilchard fishery in the Marlborough Sounds in the 1940's is probably an example of an intensive fishery which virtually wiped out a small localised population within about five years (N.Z. Marine Department 194251). Also excluded from this discussion is the exploitation of populations which are under more or less complete control and can be harvested in their entirety at any desired time: in other words, "farming". In commercial fish farming, where the product is harvested aDd marketed by the farmer, the distinction from the exploitation of wild populations is generally simple and clear-cut. In sport fisheries, on the othcr hand, the product is essentially the capture of the fish rather than the fish itself, and an almost continuous gradation exists. One can recognise, for exampl~, the following series of situations: