(10%). 



TABLE 6. TIME AT WHICH THE SAMPLES TO WHICH FIGURES 3 AND 4 RELATE 

 WERE COLLECTED. 



x/ The first six samples were not subjected to quantity -weight analysis and are therefore not 

 included in Figure 4. 



In the second half of 1955--July, August and the beginning of September- -the area of distri- 

 bution of the herring of different ages became common owing to the fact that some of the large 

 herring left the polar waters. During these months, the presence of the summer plankton complex 

 was still characteristic, and the food of all herring groups consisted of 42-45% Oikopleura , 27-36% 

 Calanus finmarchicus , 11-25% Themisto abyssorum and 4-7% young Euphausiacea (Figure 5). 



Figure 5 gives the results of the quality -weight analysis of the food of the herring in 1955 

 with separate figures for different age groups. The data given draw our attention to the relatively 

 low mean indices for 1955. 



Our material shows that, in all the years, the main feeding season of the herring is the 

 spring and summer periods (April, May, and June). From June onwards, the herring's food re- 

 quirements diminish. The amount of food present in the stomach is not large, except in the case of 

 those individuals which spawned relatively late, were unable to attain the necessary nutritional con- 

 dition during the spring months, and continued to feed intensively. The number of herring with 



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