Seasonal Distribution and Size Composition of the Purplegray Sculpin Gymnocanthus detrisus off the Mainland Coast of the Russian Waters of the Sea of Japan

The purplegray sculpin Gymnocanthus detrisus occurs at the depths between of 17 and 595 m at the temperature from –1.1 to+13.2°C off the mainland coast of the Russian waters of the Sea of Japan. In the warm period, the fish are concentrated in the middle and lower parts of the shelf, mainly at a temperature of 1.2–2.0°C, in the cold period, in the lower part of the shelf and the upper part of the continental slope at 0.6–1.4°C. The water area in the north (the waters of the Tatar Strait) is intensively used only in the warm season. The main aggregations are formed in the south (Peter the Great Bay) and in the areas of the central part of the surveyed region. Juveniles are more eurythermal than adult individuals and more adults prefer the shelf zone in all seasons, where the temperature regime is less stable than on the mainland slope.