The Distribution of the Pacific Cod Gadus macrocephalus (Gadidae), the Functional Structure of its Range in the Northern Sea of Japan, and Some Issues of Its Fishery Management

The seasonal and bathymetric distributions of the main age cohorts of Pacific cod in the northern Sea of Japan are considered based on data of bottom trawl surveys in 1980–2023. The areas of the main wintering and spawning grounds and summer feeding grounds have been clarified. The major directions and timing of seasonal migrations have been determined. The relatively shallow shelf area in the northern Tatar Strait is shown as an area for the formation of mixed aggregations by two Pacific cod populations from June to September. The effect of this factor on the accuracy of abundance estimates for Pacific cod stocks is discussed and possible recommendations for the Pacific cod fishery management are proposed.