Population structure, growth and reproduction biologyof Egrez (Vimba vimba (Linnaeus, 1758)) in the Oymapınar Dam Lake (Antalya)

This research; biological characteristics of V. vimba, sampled from Oymapinar Dam Lake on Manavgat River between April 2017 and March 2018, such as age distribution, lenght and weight distribution, growth parameters, spawning period, sex ratios, age at first sex maturity, and length and fecondity. It covers. The age of the 139 scatter samples obtained from Oymapinar Dam Lake was distributed between II-VI. The age group was the dominant age group with a rate of 55,4%. 70,5% of the samples were females and 29,5% were male. Females fork lengths ranged between 11,30-16,60 cm and their weights were between 16,42-58,05 g. The fork lengths of the male samples ranged from 10,20 to 17,00 cm, with weights between 11,47-63,75 g. Von Bertalanffy growth parameters for all individuals were determinated as L∞ = 17,78 cm, W∞ = 71,36 g, k = 0,506, t0 = -1,082 and b = 3,2378. Maximum age was V for females and VI for males. In the V. vimba samples examined, the length-weight relationship equations were found to be W = 0,012 L3,0043 (R² = 0,9434) in the total of male and female individuals. Average condition factor (KF) for overall population was calculated as 1,21 ± 0,088. Length at first sexual maturity for female and male individuals of V. vimba were determined as 15,04 cm and 12,23 cm, respectively. The first sexual maturity was found to be III for male and female individuals. Monthly gonadosomatic index values indicated that intense spawning period takes place between April and July. The average egg diameter was determined to be 0,25 mm.