Mesozooplankton was sampled by JUDAY net with a 37 cm ring diameter and mesh sizes of 125 µm. Integrated hauls (0-200 m) were usually taken. Depth of tow was evaluated by wire paid out and the angle of wire inclination. The 10-20 ml samples were preserved in 3-4% buffered formaldehyde and processed on return to the laboratory. All of copepods were identified to genus level, other taxanomic groups - to type, class, order and family levels.