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A Preliminary Study on the Morphometric Features of the European Eel, Anguilla anguilla (Anguillidae) in Gediz Lagoon (Izmir Bay, the Aegean Sea): Special Emphasis to Sexual Dimorphism

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Abstract

In this study, we aimed to state how we can contribute to an effective population management and protection by determining the morphometric characteristics of European yellow eels, Anguilla anguilla Linnaeus 1758, in the Aegean Sea population, Izmir Bay. It was found that the eye index and condition values of the female specimens are higher than those of the males. While it was determined that there was a significant difference between both sexes in 19 of 20 morphometric measurements of the head region, there was no statistical difference only in the height measurement at the nostril level of the head. In our study, the fact that specimens with ovaries were seen among the females longer than 34 cm (length group II) is remarkable in terms of early maturation in the region. The differences in head measurements between sexes indicate the existence of a dimorphic structure and these differences are in favor of female specimens.

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ACKNOWLEDGMENTS

The authors thank to the fisherman Nadir Angis in Kirdeniz who obtained the eels. We also are grateful Paul Eversfield for his valuable linguistic contributions to the final version of the manuscript. We would also like to express our gratitude towards two anonymous referees for their valuable criticism and suggestions during the peer review process.

Funding

This work was supported by ongoing institutional funding. No additional grants to carry out or direct this particular research were obtained.

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Authors and Affiliations

  1. Ege University Faculty of Fisheries Department of Basic Sciences, Izmir, Türkiye

    S. Gurkan, E. Taskavak & B. Taylan

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  1. S. Gurkan
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  2. E. Taskavak
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  3. B. Taylan
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Contributions

The contributions of the authors are as follows: S. Gurkan–statistical calculations, writing of the article; E. Taskavak–obtaining the specimens, preparing the text for publication; B. Taylan–examination of the specimens in the laboratory.

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Correspondence to E. Taskavak.

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CONFLICT OF INTEREST

The authors of this work declare that they have no conflicts of interest.

ETHICS APPROVAL AND CONSENT TO PARTICIPATE

All applicable international, national, and/or institutional guidelines for the care and use of animals were followed. The fish used in this study is a species caught by fishermen, sold on the market and consumed by consumers. The Ministry of Agriculture and Forestry and/or the Ethics Committee of Ege University stated that the report of the ethics committee is not required for fish species that are purchased at markets and bazaars.

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Gurkan, S., Taskavak, E. & Taylan, B. A Preliminary Study on the Morphometric Features of the European Eel, Anguilla anguilla (Anguillidae) in Gediz Lagoon (Izmir Bay, the Aegean Sea): Special Emphasis to Sexual Dimorphism. J. Ichthyol. 64, 37–44 (2024). https://doi.org/10.1134/S0032945224010120

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