Some Morphometric Relationships of Wels catfish (Silurus glanis L., 1758) Inhabiting Sıddıklı Dam (Kırşehir, Turkey)

Abstract

This study aims to investigate the relationships among morphometric characters of Wels catfish with total length and find the best model to assess relationships. A total of 198 fish samples was caught in Sıddıklı Dam between September 2015 and August 2016 in this study. The morphometric measures taken were: Total length (TL), Anal fin length (AFL), pectoral fin rays length (PFRL), body height (BH), head length (HL), and head height (HH). No significant differences were noted between the pectoral fin rays (PFRL) of females and males, while the significant differences were observed in the morphometric measurements (TL, AFL, BH, HL, and HH) of females and males. The linear and non-linear models were used in this study, in order to determine relationships between morphometric characters and total length. The linear model is the best fit for all relationships, so this model is preferred for all calculates. All relationships were highly significant (P < 0.001, r2 > 0.81) and the mean percent prediction errors were less than 10%. We found that AFL, PFRL, BH, HL, and HH are a good indicator for fish total length and are important for determining the length of Wels catfish. However, the best model was the relationship between anal fin length and total length for estimation of fish length in males and females. The data of the study provides novel information on relationships between morphometric characters for Wels catfish.