Some biological features of common carp (cyprinus carpio L., 1758) inhabiting the siddikli dam

In this study was examined the age structure, growth dynamics, and morphometric traits of 134 Cyprinus carpio individuals collected monthly from Sıddıklı Dam between September 2015 and August 2016. Among the six calcified structures evaluated, vertebrae provided the most reliable age estimates, with 77.5% full agreement, 3.86% mean percent error, and 3.52% coefficient of variation. Age ranged from 1 to 6 years, and the third age group was the most dominant (27.6%). The sex ratio was 39.6% female and 60.4% male, which significantly deviated from the expected 1:1 ratio (p < 0.05). Total lengths ranged from 12.8 to 36.8 cm (mean = 26.94 cm), and weights from 26.4 to 931.73 g (mean = 351.71 g). The Von Bertalanffy growth model estimated an asymptotic length (L∞) of 60.57 cm, a growth coefficient (K) of 0.10, and a growth performance index (Φ′) of 2.565. Asymptotic weight (W∞) was calculated as 4587.90 g. Length–weight relationships showed positive allometric growth in all groups (b > 3, p < 0.001). The average condition factor was 1.581, peaking in summer. Strong linear relationships (r² > 0.97) were detected among total, fork, and standard lengths. These findings contribute important biological insights into the population structure and growth of C. carpio, supporting its sustainable management in freshwater ecosystems.