Multivariate morphometric variability in sardine, Amblygaster clupeoides (Bleeker, 1849), from the Bay of Bengal coast, Bangladesh

Abstract

BackgroundSardine Amblygaster clupeoides is a reef-associated oceanic species having long-standing socioeconomic and ecological importance along the coast of Bay of Bengal, Bangladesh, but less is known about the morphometric variability of the species. To uncover this, morphometric variability of A. clupeoides based on truss network technique was employedResultsA total number of 160 specimens from four coastal regions (Sundarbans, Kuakata, Bhola, and Cox’s Bazar) of the Bay of Bengal coast were used to determine whether separate populations could be distinguished. To test the hypothesis of differentiation, each sample was subjected to morphometric measurements consisting of twenty-eight landmarks. In one way ANOVA analysis, twenty-six out of 28 morphometric measurements showed significant differences among the four populations. The principal component analysis indicated shape variation and explained 70.11% of the total variance. About 68.39% of individuals into their original group were correctly classified in discriminating space, as determined by discriminant function (DF) analysis.ConclusionMorphometric traits like body length, body depth, body diagonal, body height, head length, head depth, mouth length, anal fin length, dorsal fin length, and caudal length diagonal were mainly responsible for variation and discrimination of populations. The present investigation demonstrates that the population of the east coast (Cox’s Bazar) is morphometrically different from other populations. Future stock assessment of A. clupeoides should be considered especially on the east coast (Cox’s Bazar) while formulating management action plans.