ICHTHYOFAUNA OF THE YESIL RIVER

Abstract

This article examines the current state of the ichthyofauna of the Yesilriver. On the border of Kazakhstan on the Yesilriver, 19 species were identified, including 14 native and 5 acclimatizers. Of the 19 species, 11 species of commercial fish are widely distributed, including roach, river perch, bream and northern pike. The size structure of the fish population under study has not changed significantly in recent years, but 8+ and 9+ age-related fish are observed in the population of roach and the river perch. In the sex ratio, it was found that all fish had a predominant uterus. Absolutely-individual fertility varies in a wide range, it is in the roach -3,96-95,4 thousand caviar, in bream -4,98-139,41 thousand caviar, in northern pike -3,16-29,84
thousand caviar, in river perch-4,01-41,16 thousand caviar, in tench-38,42-216,3 thousand caviar, respectively. According to the biological characteristics of widespread fish, the growth rate was determined by low. But the state of their population is normal.