DISTRIBUTION OF FISH SPECIES IN THE NORTHERN WATERS OF THE CASPIAN SEA

The article describes the distribution of fish in the northern part of the Caspian Sea and their biological indicators. As part of the research work, 18 species of fish belonging to 7 families were caught. The article is devoted to the analysis of the features of the modern distribution of ichthyofauna in the northern waters of the Caspian Sea. According to the results of the study, it was found that the spatial distribution of fish species directly depends on hydrological conditions, fluctuations in water salinity, depth fluctuations and the nature of the nutrient base. In the structure of the ichthyological community, there is a predominance of such ecologically flexible species as Abramis brama, Rutilus rutilus and Sander lusioperca, which indicates their high adaptability to the conditions of the northern Caspian Sea. In addition, the proportion of sturgeons remains relatively low, and their distribution is explained by the limited spawning grounds and the influence of anthropogenic factors. The data obtained will make it possible to assess the state of fish resources in the northern part of the Caspian Sea, develop scientifically sound recommendations for the conservation of biological diversity and sustainable development of fisheries.

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