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

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.