Alien Species of the Lower Volga and the Caspian Sea: Fish Fauna and Food Resources (Intentional Introduction)

Based on long-term monitoring studies, the results of the intentional introduction of fish and invertebrates into the Volga-Caspian fisheries basin have been analyzed. The findings show successful naturalization in 5 out of 16 cases for the alien fish, and in 2 out of 3 cases for the alien invertebrates. Significant attention has been given to the biological characteristics—distribution, qualitative structure, and catch rates—of the golden grey mullet (Chelon auratus) and herbivorous fish, including the grass carp (Ctenopharyngodon idella) and the silver and bighead carps (Hypophthalmichthys molitrix, Aristichthys nobilis), which have become commercially important due to their widespread naturalization.