Biochemical genetics in marine fisheries management and conservation

Abstract

Species of fish, like most organisms, aquatic or terrestrial, do not exist as one continuous or homogeneous population. Rather, they consist of a collection of populations that can be recognized on the basis of a variety of characters: they may occupy different geographical areas: they may originate from different spawning grounds, as larvae or juveniles they may feed in different nursing grounds; they may consist of different age groups that form discrete schools or as adults they may return to different spawning areas with a higher or lower degree of fidelity: These are some of the characters on the basis of which one may recognize a 'population structure' in a species of fish. In fisheries, the important question is whether the structure is permanent enough to allow for the accumulation of genetic differentiation among populations or whether the structure is transitional and short-lived, followed by a stage of thorough mixing that reconstitutes the next generation in a random fashion