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Although Eurasia's Caspian basin once supported the world's richest and most diverse complex of sturgeon species, recent human activities have decimated populations of these ecologically and economically important fish. All five anadromous Caspian sturgeon species are critically endangered, and the potamodromous sterlet is also threatened. The precipitous decline of these species is due to a combination of factors that includes illegal, unreported, and unregulated (IUU) fishing; destruction of feeding and spawning habitat; water pollution; and the environmental consequences of climate change. International efforts are currently underway to re-establish sustained naturally reproducing sturgeon populations in the basin. Here, we update and review the status of sturgeon in the Caspian Sea with emphasis on the northern basin and the inflowing Volga and Ural rivers. We then focus on efforts to restore sturgeon in the Ural, which originates in Russia and flows through Kazakhstan before entering the Caspian Sea. With nearly ideal hydrological conditions for sturgeon, the Ural is the basin's sole remaining river that allows migrating sturgeon unimpeded access to potentially productive spawning grounds. The challenge of re-establishing sturgeon in the Ural River exhibits the classical characteristics of wicked problems: ambiguous definitions, changing assumptions and unanticipated consequences, tradeoffs and economic dependencies, an incomplete and contradictory knowledge base, and no straightforward pathway toward a final solution. This challenge is examined here for the first time from the perspective of its wicked dynamics, with consideration given to approaches that have proven effective elsewhere in resolving wicked environmental problems. [ABSTRACT FROM AUTHOR]

Aim. The aim of the study is to analyze the current state of artificial reproduction of the Caspian sturgeon and to identify the problems of reducing efficiency and ways to solve them.Discussion. The current critical state of the Caspian sturgeon, which accounts for up to 90% of the world's related resources, is of concern to the entire community, due to the threat of extinction of these relic individuals on the planet. This can be prevented by increasing the efficiency of reproduction. However, natural reproduction is practically reduced to zero, so the real and only possible solution is artificial reproduction. This analytical review presents five tasks, the successful solution of which will improve the current state of artificial reproduction in the Volga‐Caspian basin. The main task is the provision of fish breeding processes with producers, which, in the absence of fish of natural generation, are derived from brood stocks. Of particular concern is the threatened state of the Caspian beluga and stellate sturgeon. It is necessary to increase the release of their juveniles, for which financial stimulation of this activity is necessary. It is necessary to move more actively to the release of juveniles of an enlarged (7‐10 g) size and their export to feeding places in the waters of the Northern Caspian, which will contribute to an increase in fishing return.Conclusion. It is necessary to increase funding for research into the reproductive function of females and for artificial generation, as well as for the maintenance of production herds – a golden fund for restoring natural reserves. The attention of all the Caspian states should be drawn to the intensification of activities for the artificial reproduction of these unique fish species in the Caspian basin.