The Sea of ​​Azov shows a tendency towards restoration of sturgeon populations

 

Regulation of the flow of spawning rivers: the Don (1952) and Kuban (1973) gradually led to the almost complete loss of natural spawning, so during the last decades of the last century, the stocks of Azov sturgeon fish were formed mainly through artificial reproduction.

 

The effective work of fish farms made it possible to achieve by the mid-90s. the level of total reserves of Russian sturgeon and stellate sturgeon - more than 90 thousand tons. At the same time, the commercial stock of sturgeon fish created by industrial reproduction was estimated at 60 thousand tons and allowed to catch annually without harm to the population on average up to 1.5 thousand tons per year.

 

By 2000, due to the mass illegal catch of sturgeon fish, mostly by poachers of the neighboring state, artificial reproduction did not compensate for the decrease in their population in the Azov Sea, thus the commercial value was lost. The stock of Russian sturgeon sharply decreased to 5 thousand tons, stellate sturgeon - to 4 thousand tons. As a forced measure aimed at preventing their complete extermination, a ban on fishing was introduced in the Azov basin. However, even after the cessation of official fishing, the stocks of valuable fish species continued to rapidly decrease due to illegal fishing.

 

As a result, by 2011-2013, during the trawl surveys conducted by AzNIIRKH (currently the Azov-Black Sea branch of the Russian State Research Center All-Russian Research Institute of Fisheries and Oceanography (VNIRO)) in the Sea of ​​Azov, sturgeon fish ceased to be recorded in the test catches.

 

After the Republic of Crimea, Donetsk People's Republic, Zaporizhzhya and Kherson regions joined the Russian Federation, the Sea of ​​Azov became an internal sea of ​​Russia and came under the control of Russian fishery protection agencies, which significantly reduced the impact of illegal fishing.

 

Since 2014, there has been a tendency to restore sturgeon stocks, especially Russian sturgeon. This is due to increased protection of aquatic bioresources of the Sea of ​​Azov and an increase in the number of sturgeon juveniles released by fish hatcheries from 2-3 million specimens in 2011-2012. up to 5-6.5 million specimens per year at present.

 

As a result, over the period from 2014 to 2023, the stock of Russian sturgeon increased from virtually zero to over 2,000 tons. At the same time, a multi-age population structure was formed. In the Sea of ​​Azov, individuals longer than 150 cm and weighing over 18-24 kg began to be found again.

 

Over the past 3-5 years, scientists from the Azov-Black Sea branch of VNIRO have noted a sharp increase in the number of Russian sturgeon and stellate sturgeon as by-catch in fixed seines installed in the coastal 5-kilometer zone of the Sea of ​​Azov. Every year, not only the number of sturgeon fish increases significantly, but their size and age composition also expands. Beluga is also noted in the catches.

 

The All-Russian Research Institute of Fisheries and Oceanography pays special attention to monitoring coastal fishing with fixed nets in order to obtain information on sturgeon by-catches in commercial fishing gear and their distribution in the coastal part of the Azov Sea. This information significantly supplements the results of trawl surveys in the Azov Sea and allows for a more accurate assessment of the stocks of Azov sturgeon.

 

The change in the legal status of the Azov Sea to an inland sea of ​​the Russian Federation made it possible to implement the scientific recommendations of the Azov-Black Sea branch of VNIRO on the restoration of sturgeon stocks. Real prerequisites have emerged for increasing the commercial stocks of these particularly valuable fish species, which could become a unique world example of restoring the species to a biologically safe level.

 

Press service of VNIRO