Management Implications for Different Genetic Stocks of Largemouth Bass (Micropterus salmoides) in the United States

Abstract

Genetic differences exist among 90 largemouth bass (Micropterus salmoides) populations from different geographic regions of the United States. Genetic variation at 28 loci was determined through the use of vertical starch gel electrophoretic analyses. Allelic polymorphism was observed at 16 of these loci. Marked differences in allele frequencies at six of these loci exist among the populations. Distinct north–south clinal distributions of the alleles at the MDH-B, SOD-A, IDH-B, and AAT-B loci suggest a possible involvement of the associated enzymes in the thermal tolerance/preference limits for this species.We conclude that one or more of these enzymes may be directly involved in temperature tolerance/preference or indirectly associated with temperature-related effects. In either instance, selection (if occurring) may be acting upon the enzyme locus or genes closely linked to it. Through a combination of ecological and genetic principles, it is becoming increasingly feasible to select or construct specific populations of marine or freshwater fish optimally suited for specific environments. Fisheries management programs would benefit from the application of these principles. Multidisciplinary approaches of this nature are essential to maximize the successful conservation and management of our natural resources.Key words: largemouth bass, allele, loci, polymorphism, selection, population