Food composition, daily rations, and volumes of consumption for walleye pollock in the Okhotsk Sea in the 2000s

Abstract

Mean daily ration of walleye pollock (various size) in the Okhotsk Sea is estimated as 2.3 % of fish body weight in spring, 5.4 % in summer, 3.4 % in autumn, and 2.2 % in winter. Its total annual consumption is amounted as 98.88 · 106 t on average for the 2000s. Zooplankton dominated in the diet, with its mean annual grazing 80.42 · 106 t, including 41.84 · 106 t of euphausiids (44.1 % of total consumption) and 19.83 · 106 t of copepods (20.9 %), while only 11.29 · 106 t of nekton (11.9 %) was grazed annually by pollock. Pollock grazed annually 16.7 % of the Euphausia stock, 5.0 % of the Copepoda stock, 40.7 % of the Amphipoda stock, and 1.1 % of the Sagitta stock, on average. About a half (50.7 %) of the nekton total consumption in the Okhotsk Sea is provided by pollock.

Keywords

• охотское море
• минтай
• состав пищи
• суточные рационы
• выедание
• кормовые объекты