Otolith shape analysis as a tool for stock discrimination of the black scabbardfish, Aphanopus carbo Lowe, 1839 (Pisces: Trichiuridae), in Portuguese waters


  • Inês Farias Unidade de Recursos Marinhos e Sustentabilidade, INRB
  • Ana Rita Vieira Departamento de Biologia Animal and Centro de Oceanografia, Faculdade de Ciências da Universidade de Lisboa
  • Leonel Serrano Gordo Departamento de Biologia Animal and Centro de Oceanografia, Faculdade de Ciências da Universidade de Lisboa
  • Ivone Figueiredo Unidade de Recursos Marinhos e Sustentabilidade, INRB




black scabbardfish, otolith, contour, shape, Fourier descriptors


The variability in otolith contour shape of black scabbardfish (Aphanopus carbo) from Portuguese waters was analysed for stock discrimination purposes. The contour shape of otoliths from specimens caught off mainland Portugal, Madeira and Azores archipelagos was digitised and extracted according to the closed-form Fourier analysis technique. Mainland and Madeira specimens were compared through the adjustment of a MANOVA model to the normalised elliptic Fourier descriptor (NEFDs) obtained for the otoliths of 200 females and 200 males sampled at each area. Significant differences were found between areas and between sexes; the interaction term was not statistically significant. The effect of the area also proved to be significant when samples from the three regions were considered. These results were further supported by the discriminant analysis of the individual NEFDs for which the correct classifications were 87.5-89% when they were considered by sex and total length for the mainland and Madeira, and 90.9-97.7%, when NEFDs from the three areas were compared by sex and fish length. Otolith contour shape was shown to be a possible tool for differentiating between black scabbardfish stocks in the NE Atlantic.


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How to Cite

Farias I, Vieira AR, Serrano Gordo L, Figueiredo I. Otolith shape analysis as a tool for stock discrimination of the black scabbardfish, Aphanopus carbo Lowe, 1839 (Pisces: Trichiuridae), in Portuguese waters. scimar [Internet]. 2009Dec.31 [cited 2023May31];73(S2):47-53. Available from: https://scientiamarina.revistas.csic.es/index.php/scientiamarina/article/view/1145




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