Determination of some biological characteristics of Atherina boyeri distributed in Seyhan Dam Lake

In this study, the reproductive and growth characteristics of Atherina boyeri distributed in the Seyhan Dam Lake were examined. Specimens were collected monthly between January 2023 to January 2024 using a beach seine net in the Seyhan Dam Lake. During the study, a total of 40920 numbers were caught, of which 5201 length and weight were measured, while age determination was carried out using otoliths on 291 specimens. The findings revealed that the female-to-male sex ratio was 1/1.3. Based on the monthly variation of the Gonadosomatic Index (GSI), reproductive activity was observed to occur between February and June, with the peak spawning was between April and June. The length at first sexual maturity was found to be 7.81 cm. The slope (b) of the length-weight relationship differed between sexes, with male individuals having a slope of 3, while females exhibited a slope greater than 3. Additionally, the condition factor was calculated as 0.0078 for females and 0.0068 for males. Growth parameters were estimated using the von Bertalanffy growth model, where the asymptotic length (L∞) was taken as the length of the largest captured specimen (L∞ = 11.5 cm), and growth parameters were determined as K= 0.76 year - ¹ and t0 = -0.46 years.