Environmental problems of the Khadzhibey estuary and prospects for its fishery exploitation

Purpose.To study the peculiarities of the formation of the hydrological-hydrochemical regime and the ichthyocomplex of the Khadzhibey Estuary, to analyze the state of the ecosystem components of the water body in connection with the prospect of its further fishery exploitation. Methodology.Generalized results of studies conducted during 2000–2021 were used in the course of work. An analysis of the available data on the formation of the current hydrological and hydrochemical regime of the estuary, the peculiarities of the formation of the ichthyocenosis, the current composition of ichthyofauna, and the results of fishery activities was carried out. Hydrological, hydrochemical, hydrobiological and ichthyological studies were carried out according to standard methods [1, 2]. The materials obtained during field studies were processed at the laboratory of the Department of Aquatic Bioresources and Aquaculture of ODEKU. Findings. A retrospective analysis of the peculiarities of the formation of the aquatic ecosystem of the Khadzhibey estuary as a water body for the storage of purified household effluents was carried out. The causes and results of anthropogenic transformation of the water body, the stages and peculiarities of the formation of the ichthyological complex, the organization and current state of culture-based fisheries were revealed. Ways to improve the hydrological and hydrochemical state of the water body are being examined. Artificial reefs are one of the most important directions that should be developed in the water area of the Khadzhibey Estuary. The formation of the biota of these engineering structures will allow not only increasing the abundance and production of some fish species, e.g., gobies (Gobiidae), but also significant improving the ecological condition of the water body. Prospective directions for the development of aquaculture through the targeted formation of polyculture with the introduction of flatfishes (Pleuronectidae), turbots (Scophthalmidae), gobies (Gobiidae), sturgeons (Acipenseridae) and salmonids (Salmonidae) are proposed. It is shown that one of the promising forms of fish farming that can be successfully developed in the Khadzhibey Estuary is cage aquaculture aimed at growing valuable brackish and freshwater fish species. Originality. For the first time, an analysis of the peculiarities of the formation of the ecosystem and the ichthyological complex of the Khadzhibey Estuary as a water body is presented, the prospects for its further functioning are examined, and the promising directions of aquaculture development are determined. Practical value. The obtained results can be used to develop measures to stabilize and improve the state of the Khadzhibey E stuary ecosystem and introduce new, promising directions for the development of aquaculture.