Since 2001, there has been a decrease in the number of pike perch in the Azov basin for a number of reasons: high level of IUU fishing; reduction and then complete cessation of artificial reproduction in the Azov-Don region; reduction of the feeding area in the Azov Sea due to increased salinity.
The marginal stock level for pike perch (the stock at which catching the species is prohibited) is 2 thousand tons. However, by 2010 this value had become less than 0.5 thousand tons. In this regard, after a series of studies, a decision was made to ban commercial and amateur fishing for pike perch from 2017.
Currently, the negative prerequisites for the formation of the pike perch stock remain, but the adopted scientific recommendations to limit its exploitation have yielded results. Despite the very unfavorable conditions for reproduction and habitat, the pike perch stock has stopped declining. Its individuals have found new habitats where the core of producers can be preserved, which will allow preserving the genetic fund of the population and, when favorable hydrological conditions occur, restoring the pike perch stock.
These conclusions are supported by monitoring studies of the Azov-Black Sea branch of the State Research Center of the Russian Federation "All-Russian Research Institute of Fisheries and Oceanography" (VNIRO). Constant observations carried out by the branch employees at the fish passage lock of the Kochetovsky hydroelectric complex on the Don River have shown that pike perch is found in the Don regularly, and during the autumn-winter migrations, its number per transfer reaches 400-800 specimens.
Previously, the main run of semi-anadromous pike perch in the Don was noted in April-May, and only a small number of it entered in the fall. Today, the peak of pike perch counting occurs in the autumn period. Such a redistribution of peaks of the run indicates that, in conditions of increasing salinity of the Sea of Azov and Taganrog Bay, the predominant habitat of the semi-anadromous form of pike perch has shifted to the lower Don.
Thus, the ban on catching semi-anadromous pike perch introduced in 2017 brought its positive results, as the decline in stocks of this fish species has ceased. At the same time, the Don River has become one of the main centers of concentration and preservation of the genetic fund of the pike perch population. With further protection of this species, it has every chance of recovery when favorable hydrological conditions occur.
Press service of VNIRO