Warming of the Sea of Japan Drives Russian Far East Sardine Migration Northward, Tsushima Stock Potential Catch Up to 200,000 Tonnes

Ilya Shestakov, head of the Russian Federal Fisheries Agency, confirmed on 12 November in a broadcast on the Russia 24 television channel that Far East sardine (Sardinops sagax, commercially known locally as ivasi) has entered the Primorye subzone, opening a new commercial fishing window for Russia's domestic fishing fleet. Fisheries management authorities expect that fishing for this species will play a decisive role in balancing Russia's cumulative national catch performance for this fishing season.

Research assessments by the Russian Federal Research Institute of Fisheries and Oceanography (VNIRO) show that the migration pattern of this pelagic species has undergone structural change. The Pacific stock has almost ceased its historical approach to the coast of the southern Kuril Islands, while the biomass of the Tsushima stock associated with the Sea of Japan basin is on an upward trend. Between 2016 and 2024, Russia's core fishing grounds for this species were concentrated around the southern Kuril Islands; in the 2025–2026 cycle, changes in ocean hydrological conditions have shifted the migration route of the Pacific stock substantially toward the open waters of the Pacific, away from the usual coastal fishing range. At the same time, rising seawater temperatures in the Sea of Japan are driving the fish northward: reaching the Tatar Strait in summer and forming dense commercial shoals in Peter the Great Bay by early autumn.

Technical estimates by the VNIRO Pacific branch consider that, provided resource replenishment continues and supporting fishing facilities are in place, the potential catch of the Tsushima stock could reach up to 200,000 tonnes.

In terms of actual operating data, the average daily catch per vessel in Peter the Great Bay in the second half of October was 23.3 tonnes. Current fishing is mainly undertaken by medium-sized trawlers, and the onboard processing capacity of such vessels has clear limitations. In addition, the main dense concentrations of fish are located within the statutory 12-nautical-mile coastal protection zone, where Russian maritime regulations strictly prohibit the operation of large processing trawlers.

With favourable ocean conditions continuing and the operating scale of the specialised medium-sized fleet expanding, Far East sardine is positioned as a key resource supporting raw material supply for Russia's aquatic product processing industry.