over a period of several years (15) . 



In the pre-spawnlng concentrations of Murman herring spawning for the first time, we 

 found the young specimens having the highest rate of growth, \nrtiich, as we established, arrived 

 from the schools of fat herring of the littoral zone. 



Only single specimens of Murman herring, having an exceptionally higfi rate of growth, 

 mature at the age of 4 years . Mass maturation begins at the age of 5 years . Only the fish with the 

 highest rate of growth (having the mean length of at least 22.5-23 cm.) become sexually mature at 

 that age while the specimens developing more slowly mature 1 or 2 years later. 



This theory has been confirmed by data on the growth rate of herring, which attained sexual 

 maturity at varying ages (see table 3) . 



The specimens becoming sexually mature at the age of 5 years have the highest rate of 

 growth; the growth indices of the herring maturing at the age of 6 years are somewhat lower and of 

 those becoming mature at the age of 7 - still lower. 



TABLE 3. GROWTH RATE OF THE HERRING THAT REACHED SEXUAL MATURITY 

 AT THE AGE OF 5, 6 and 7 YEARS (PRE-SPAWNING CONCENTRATIONS 

 -January, 1939). 



In early April, 1939, the exploratory fishing trawler "Beluga" discovered on Malangen Bank 

 these schools of herring of the 1934, 1933 and 1932 year classes spawning for the first time. This 

 information, as well as observations conducted on board the exploration boat "Persey-II" in 1949, 

 showed that the spawning of first-time spawners takes place in the north-eastern half of the Lofoten 

 spawning region 30-40 days following the spawning of older herring. 



The process first-time maturation of Norwegian herring has not been studied thus far. It 

 doubtless occurs in a manner similar to that of the Barents Sea herring namely: large specimens 

 become mature changing from the fat fish stage to the maturing stage, earlier. They arrive in the 

 spawning grounds after the spawners of older age groups and reproduce at the end of March, even 

 beginning of April . 



Iceland herring first-time spawners probably populate the waters to the south-west from 

 the island. 



FEEDING MIGRATIONS OF ADULT HERRING. 



The study of migrations of Atlantic-Scandinavian herring of older age groups was initiated 

 by the Polar Institute of Fisheries and Oceanography in 1939, when, in summarizing data collected. 



28 



