Water Level and Temperature as the Main Factors Responsible for the Formation of Conditions for Aboriginal Fish Fauna Effective Reproduction in the Kremenchuk Reservoir

Modern dynamics of the main abiotic environmental factors responsible for fish fauna effective reproduction in the Kremenchuk Reservoir are discussed in the paper. Annual dynamics of water level and temperature were analyzed. It has been found that the main factor responsible for the rate of breeding stock maturation in the Kremenchuk Reservoir is water temperature dynamics rather than spawning temperatures. It is underlined that the operation of hydroelectric facilities and the spawning campaign must be synchronized to ensure sustainable fisheries. The drainage of spawning grounds in low-water years results in the decrease in their area and, as a consequence, in the formation of low-yielding generations. It is recommended to optimize the annual dynamics of water level according to the needs of fisheries.