PrimoryeSea
 Pacific herring, Chipea harengus
Pacific herring        The outer appearance of this species shows that it is a pelagic fish that spends most of its life in movement. A typically gregarious fish, it is born to live and die surrounded by its own ilk. A solitary specimen would fall into a state of stress, stop feeding and quickly perish. Herring life essentially involves consecutive movement from fattening and wintering sites to spawning sites, often quite remote. Observers used underwater equipment to register the state of herring at nighttime as something similar to sleep, during which the fish rest, having dispersed in various postures (belly or tail up).
   In summer, the herring intensely fattens near the coastline, feeding on small plankton organisms. After fattening, their fat content reaches 18-25%. Large specimens of up to 50 cm long are especially fat, sometimes weighing 0.7 kg each.
   The Pacific herring population fluctuates considerably. The fish become sexually mature in the second-third year of life. Herring makes its first approaches to the coastline under ice. In Peter the Great Bay, it spawns from March through May when water temperatures range from +1.5 to +8oC on shallows of 1-15 m deep. It lays roe on rocks, sea grasses and algae. The Pacific herring is a highly valuable commercial species. To enhance its productivity, biologists have developed methods for creating artificial spawning grounds.
  
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