The Pacific Herring (Clupea pallasii) Distribution in the Tatar Strait, Sea of Japan, in April–June

The spatial distribution of the Pacific herring in the Tatar Strait in spring (April–June) is considered based on the data of the bottom trawl surveys in 2002–2022. It is shown that herring occur everywhere in the Tatar Strait in this season, with the main aggregations distributed at depth shallower than 100 m and a near-bottom water temperature of 0 to 2°C. The sites of prespawning herring aggregations are rather stable despite some interannual variations caused by thermal conditions. The densest fish aggregations typically occur in the northern part of the strait, near the spawning grounds of the De–Kastri herring population. Fish from 10- to 28-cm long dominate catches. Herring of the Sakhalin-Hokkaido population aggregate mainly over the Chekhov–Ilyinsky shoal. There, fish from 16- to 30-cm long form the stock structure, while the portion of fish larger than 25 cm has increased in recent years. Herring of the Plastun–Nelminsky population were present in minimal abundance in the southwestern Tatar Strait.