Pasture Fish Farming in the Reservoirs of the Volga-Kama Cascade as One of the Directions for the Implementation of the Blue Bioeconomy Concept

Abstract

In the second half of the twentieth century, many rivers were subjected to the most powerful of all known anthropogenic impacts—channel regulation. This led to the creation of a cascade of large reservoirs on the Volga River, which radically changed the hydrological, hydrochemical and hydrobiological regimes of water bodies and became the most significant for the ecosystems of the basin and natural landscape complexes. At the same time, as practice has shown, the multifunctionality of the reservoirs, unfortunately, does not allow to fully realize their potential fish productivity. Currently, there are forage resources in the reservoirs of the Volga-Kama cascade, which are either not used at all, or are poorly used by representatives of the existing ichthyofauna. The main task of the research was to assess the value of the commercial fish stock and the production of the links of the food chain, which is transformed by fish, and to determine at the expense of which links it is possible to increase the volume of fish production and its withdrawal without violating the functional integrity of the ecosystem. The dynamics of the aggregate commercial stock of the main fish species of the Volga-Kama cascade of reservoirs in recent years does not have a clearly pronounced trend, which may indicate the relative production stability of the ichthyocenosis. The calculation of the receiving capacity of the reservoirs of the cascade shows the possibility of increasing the catch by 18 thousand tons, while the cost of the expected fish products will more than 4 times exceed the cost of the planting material. The creation of a complex of pasture fish farms will have a beneficial effect on the ecological state of water bodies, will make it possible to use the fodder base more fully and efficiently, will ensure biological reclamation, and will make it possible to obtain additional, high-quality fish products.