The development of the eggs of White Sea herring takes place in a littoral distinguished 

 by great inconstancy of external conditions, especially in the spring period. 



For example, the development of the eggs of the small Kandalaksha herring begins at a 

 below-zero temperature and ends when the water has been considerably warmed up. Other herring 

 in this connection enjoy more favorable conditions. Thus the spawning places of the Atlantic herr- 

 ing are at a depth of more than 50 metres, and the development of the eggs of this herring takes 

 place under more uniform environmental conditions. 



The biological peculiarities we have mentioned have a great importance for the organiz- 

 ation of a rational herring fishery in the White Sea . They show that the stocks of White Sea herring 

 are in need of cdreful conservation and that the conditions of reproduction have a big influence on 

 the number of these herring. And yet the reproductive ability and the conditions of reproduction 

 of the fish are considerably vitiated by the present fishing methods . 



EXiring the last 30 years, very real changes have taken place in the White Sea herring 

 fishery. A spring catch of herring has become general in all regions. As late as the 20s, in most 

 fishery regions of the White Sea, herring were caught only in autumn or winter. A spring catch 

 either did simply not occur, or else it was insignificant. At the present time, it has become funda- 

 mental everywhere (Table i ). 



TABLE 1. HERRING CATCHES IN DIFFERENT YEARS OF THE FISHERY 

 (IN PERCENTAGES) . 



Already in pre-war years, the spawning herring were cau^t in a larger quantity than the 

 fat herring; in the post-war period, the catch of this herring increased still more . During the 

 last few years, both in the Onega and in the Dvina gulfs, the greatest quantity of herring was caught 

 during its spawning period. At the same time, there was a decrease in the fishery for fat and 

 especially for pre-spawning herring. 



If, in pre-war years on the eastern coast of Onega Gulf, the winter catch of herring 

 amounted to 40% of the yearly catch, in post-war years on the other hand, catches of pre-spawning 

 herring dropped by half. At the same time, the catch in the spring period increased and the catch 

 of spawning herring began to constitute about three-quarters of the annual catch. In Dvina Gulf, 

 the catches of spavraing herring have latterly increased notably, but those of pre-spawning herring 



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