Morphological and Genetic Characteristics of Scomberomorus Species in the Indo-Pacific: Implications for Fisheries Management

Abstract

Mackerels belonging to the Scomberomorus genus are pelagic fish of considerable commercial importance and are distributed throughout the Indo-Pacific region. The morphological and genetic stock structure of the fish species targeted by fisheries are essential components that constrain the identification of the stocks available for fishing. This work carries out a preliminary morphological and genetic identification of Scomberomorus species through body measurements and molecular data analysis. Karyometric analysis revealed differences in somatic characteristics, fin profiles, and a number of vertebrae, ribs, and fin elements constituting the distinctive taxonomic markers. As expected, analysis using mtDNA sequences and nuclear DNA genetic markers shows a relatively high genetic variability within stocks and a high level of genetic differentiation across geographic stocks. Such results imply low genetic connectivity between some populations, possibly due to specific marine geographical barriers and environmental scalars. When morphological and genetic information are combined, there are clear implications for improving species identification and the delimitation of stock boundaries. The outcomes serve as valuable information on population distribution and regions that facilitate effective regional management of Scomberomorus species for fisheries. Recommendations include setting Transboundary Management plans and applying several management strategies to sustain Scomberomorus in the Indo-Pacific region.