Mesozooplankton was collected in vertical hauls covering three layers: 0 m - upper border of thermocline, the layer of thermocline, lower border of thermocline - 200 m with Juday net with mesh size 0.145 mm and a mouth area of approximately 0.1 m**2. Depth of tow is evaluated by wire paid out and the angle of wire inclination. Nansen's closing device.