Ladik Gölü (Samsun, Türkiye)'ndeki Çapak Baliği, Abramis brama (L., 1758)'nin Yaşi, Büyümesi ve Üreme Dönemi

Abstract

This study is the first comprehensive investigation on the biological characteristics of freshwater bream, Abramis brama (L., 1758) living in Turkiye’s inland waters. The length and weight distributions, age and sex compositions, length-weight and length-length relationships, parameters of the von Bertalanffy growth equation, condition factor values, and reproductive period of the fish in question were examined by using a total of 722 specimens captured on a monthly basis from Lake Ladik (Samsun) between November 2009 and October 2010. Fork lengths of fish ranged from 8.1 to 44.6 cm and their weights ranged from 8 to 1790 g. The overall sex ratio (F:M) was 1:1.58. The maximum age was 8 years. The length-weight relationship was found as W=0.0081CB3.229 for females and W=0.0103CB3.148 for males. All relationships among total length, fork length, and standard length were highly significant (P<0.001, r2=0.99). The parameters of the von Bertalanffy growth equation were calculated as L∞=84.95 cm, W∞=13732.62 g, k=0.08 (year-1), t0=-0.54 year for females and L∞=89.20 cm, W∞=14209.72 g, k=0.06 (year-1), t0=-1.13 year for males. The mean values of the Fulton’s condition factor (K) for females, males, and all individuals were 1.63, 1.58, and 1.59, respectively. Mean K displayed an upward trend with reference to age and length groups. The highest value of mean K was observed in April (K=1.75) for females and August (K=1.64) for males. According to the monthly variation of gonadosomatic index (GSI), the reproduction takes place between April and June