In recent years, sterlet populations of mainly “factory” origin have been formed in the rivers Sheksna, Mologa, Oka, Dnieper, Kuban and Don, as well as Uglich, Gorky and Kama reservoirs, the growth of which is most dependent on the volume of release of its young. The structure of “factory” sterlet populations in rivers and reservoirs of the European part of Russia differs from native populations of this species in a number of commercial and biological features. In the above-mentioned water bodies for the period from 2019 to 2023. The share of sterlet in control catches has increased dramatically, despite the fact that the habitat conditions of this species and the degree of fish protection measures have not changed significantly. Sterlet of “factory” origin in rivers and reservoirs inhabits sturgeon biotopes uncharacteristic for this species. The indicators of linear and weight growth of the “factory” sterlet in younger age groups are on average higher than similar indicators for sterlets from natural spawning. Males strongly predominate in the sexual composition of the samples of the “factory” sterlet and to date no producers with post-spawning gonadal changes have been found. The results of accounting for early juvenile fish during the period of sloping migrations in the upper reaches of the Oka, Dnepr rivers, as well as the Saratov reservoir showed that, despite the relatively high concentration of mature sterlet in the places of accounting for juveniles and the location upstream of spawning grounds of lithophilic fish species, sterlet larvae in catches of ichthyoplankton traps from producers of “factory” origin to the present not detected.
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