BIOLOGICAL CHARACTERISTICS AND CURRENT ASSESSMENT of the COMMERCIAL STOCK of the ROACH Rutilus caspicus (Jakowlew, 1870) (CYPRINIDAE) IN THE ZHAIYK-CASPIAN BASIN

In this work, materials are presented on the dynamics of the spawning population of the bleeds in the yayyk river. It is shown that the river zhayyk with a pre-forest space includes a significant area, which is an area of migration of commercial fish from the pre-river to the river and back. In all seasons of the year, the formation of fish stocks foraging young and adult fish is formed throughout the water area. The article analyzes the intensity of spawning migration of producers to spawning grounds of the Yayyk river and their biological characteristics. It has been revealed that the number of fish older than the age group is decreasing every year. Scientific studies allow us to assess the characteristics of spawning migration of the bleed and to determine its fish stocks and to recommend commercial seizures.The scientific data obtained on the state of fish stocks, their biological characteristics (growth rate, fertility, yield of young people, food supply) are the basis for the calculation of catch quotas and the development of a strategy for the management of bioresources.It has been determined that in the qualitative structure of the producers of bleeds, migrating to the places of location, there was a further increase in the length and weight of both females and males. The size of the wobbles from non-water river catches ranged from 15 to 34 cm (average 22 cm) and weigh 79-729 g (average 271 g). The average length of females is 24 cm, males - 20 cm, the average mass - 404 and 139 g respectively. The spawning herd of venova in spring 2019 consisted of 6 age groups in the range of 2 to 7 years. The 3-5 year before - 96.1% prevailed. The average age of the population is 3.9 years, which is lower than in previous years.

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