The investigation of some population parametres of Alburnus mossulensis (Heckel, 1843) in Keban Dam Lake

This thesis study was carried out to determine the population distribution of Alburnus mossulensis (Heckel, 1843), living in the Keban Dam Lake and known as silver fish, as well as some population parameters such as growth, growth rates and condition factor. A total of 260 fish samples were obtained using a round mouth scoop from Keban Dam Lake between June 2018 and May 2019. After the length and weight measurements of fish were done in laboratory environment, age determinations were made by using scale material. Some population characteristics were determined by standard methods. To determine the growth parameters of von Bertalanffy, the FAO-ICLARM FISAT II package program was used. In the population distributed between age groups I-VII, 53.85% female and 44.23% male samples were found and 1.92% of the sample type did not reach maturity. Female/male ratio was determined as 1:0.82. As a result of the X2 test, it was observed that the difference between sex ratios in all age groups was statistically insignificant (p>0.05), female/male ratio was not different from 1:1. Regression coefficient (b) in females b = 3.5555 (positive allometric growth), b = 3.2131(positive allometric growth) in males and b = 3.4707 in all individuals (positive allometric growth) has been determined. The total length of the individuals examined was 9.5-18.2 cm and their weights ranged from 5.4-59.5 g. In all subjects the condition factor values vary between 0.4 and 1.15. The highest proportional growth (20.36%) was between I-II age group. Von Bertalanffy growth parameters of the female population; L∞= 22.97 cm, K=0.12 year-1, t0=-3.84 years, W∞= 124.42 g, in males; L∞=22.05 cm, K=0.16 years-1, t0=-2.8 years, W∞=87.05 g and in all individuals; L∞=22.64 cm, K=0.14 years-1, t0=-3.3 years, W∞=110.86 g .The growth performance index (Φ), which was used to compare the growth parameters obtained from different studies, was calculated to be 4.15 in females, 4.35 in males and 4.27 in the general population.