September 1951, In 1950, fish of three to five years also comprised here a considerable percent- 

 age in August and September, which Is indicated in Einarsson's work (2). -' 



TABLE 18. RELATION OF STAGES OF SEXUAL MATURITY OF HERRING IN 

 AUTUMN-WINTER CATCHES 1947-48 (PERCENTAGES). 



Thus, sexually immature herring are found in all the Iceland regions but a specially large 

 number is observed to the south-west of the island, where in the winter of 1946, 1947, and 1947-48 

 they were caught in large numbers by the Icelanders. 



Off the northern coasts of Iceland, according to our observations, young herring are par- 

 ticularly common at the end of the fishing season- -in August and September. 



Distribution^ of Adult Summer Herrings 



Our researches show that the fattening of the older age categories of the summer herring 

 before and after reproduction takes place to the north of Iceland, where the older age groups are 

 always predominant . Young individuals comprise only an insignificant percentage of the catch in 

 this region. 



Table 19 gives a comparison of the age composition of the summer herring in the regions 

 of the north and south coasts of Iceland, based on the materials for 1951 . 



As regards the age composition of the summer herring, these two regions differ sharply 

 from each other. To the north of the island, herring from 7 to 14 years are predominant, while in 

 the southern region those from 4 to 8 years are predominant . Herring aged 9 years or more make 

 up 5.6% in the south and 62.1% in the north. These data lead to the conclusion that the areas of 

 distribution of young and older age groups of the summer herring are fundamentally different. Only 

 the older age categories come to the northern coasts nf Iceland from the south. 



Observations made in 1951 give grounds for supposing that the older herring leave for the 

 fattening grounds earlier than the younger individuals. Thus, in August 1951, herring of 7 years 

 and more made up 26.5% while in September the percentage of the same age categories had fallen 

 to 18.7%, since the younger ones had arrived. 



Our conclusions on the distribution of the young of the summer race are confirmed also by 



1/ In December 1950, the Icelanders caught 14,000 hectolitres of small herring in purse-seines. 



193 



