Morphometric variation among sardine (Sardina pilchardus) populations from the northeastern Atlantic and the western Mediterranean
Open Access
- 1 January 2003
- journal article
- Published by Oxford University Press (OUP) in ICES Journal of Marine Science
- Vol. 60 (6), 1352-1360
- https://doi.org/10.1016/s1054-3139(03)00141-3
Abstract
During the past decade, regional changes in the dynamics of the Atlanto-Iberian stock of sardine, and its exploitation by Portuguese and Spanish purse-seine fisheries, have increased the uncertainties in estimated trends of spawning biomass, stock abundance, and fishing mortality. Together with recent evidence for lack of discontinuities in the distribution of sardine eggs at the edges of the stock area, this casts doubts on the hypothesis that the stock is a panmictic, closed population. Sardine morphometric data (truss variables and landmark data) from 14 samples spanning the northeastern Atlantic and the western Mediterranean were analysed by multivariate and geometric methods. The analyses explored the homogeneity of sardine shape within the area studied, as well as its relation to that of adjacent and distant populations (Azores and northwestern Mediterranean). Principal components analysis on size-corrected truss variables and cluster analysis of mean fish shape using landmark data indicate that the shape of sardine off southern Iberia and Morocco is distinct from the shape of sardine in the rest of the area. The two groups of sardine are significantly separated by discriminant analysis, and their validity was confirmed by large percentages of correct classifications of test fish (87 and 86% of fish from the test sample were correctly classified into each group, respectively). There was also some evidence that fish from the western Mediterranean and the Azores form a separate morphometric group. These results question both the homogeneity within the Atlanto-Iberian sardine stock and the validity of its current boundaries.Keywords
This publication has 16 references indexed in Scilit:
- Changes in the distribution of sardine eggs and larvae off Portugal, 1985-2000Fisheries Oceanography, 2003
- The utility of image processing techniques for morphometric analysis and stock identificationFisheries Research, 1999
- An holistic approach to fish stock identificationFisheries Research, 1999
- Stocks and chameleons: the use of phenotypic variation in stock identificationFisheries Research, 1999
- Population diversity in Bay of Biscay anchovy (Engraulis encrasicolus L. 1758) as revealed by multivariate analysis of morphometric and meristic charactersICES Journal of Marine Science, 1993
- A revolution morphometricsTrends in Ecology & Evolution, 1993
- The Monotypic Sardines, Sardina and Sardinops: Their Taxonomy, Distribution, Stock Structure, and ZoogeographyCanadian Journal of Fisheries and Aquatic Sciences, 1989
- A Comment on Shearing as a Method for "Size Correction"Systematic Zoology, 1987
- An Evaluation of Morphometrics and Meristics for Stock Separation of Pacific Herring (Clupea harengus pallasi)Canadian Journal of Fisheries and Aquatic Sciences, 1984
- The Truss: Body Form Reconstructions in MorphometricsSystematic Zoology, 1982