begin catching summer herring off the nortn coast in July, when the summei herring is leaving for 

 the reproduction grounds in the southern regions, and finish catching in the last v/eek of August, 

 when a large proportion of the post-spawning herring have not yet reached the northern regions. 

 It is precisely in these two periods --at the beginning of the season and af the end-- that, accord- 

 ing to our observations, the summer herring is found in large quantities in the northern regions. 



Fridriksson (5) explains the large influx of young herring into the fjords of the west coast 

 in 1946-48 by an increase in the numbers of the summer race in those years. One can hardly agree 

 with this assumption. 



Large catches of larvae of the summer herring were observed by I. Schmidt in 1903-1904; 

 Taning in 1925, 1933, 1936, and 1946. There were large numbers of summer herring in Faxa Bay 

 in 1946-47, 1947-48. Finally, we found large concentrations of summer herring off the west coast 

 in 1951 . All these observations confirm that the summer herring during the last 50 years has had 

 considerable wei^t in the total stock of herring in the Iceland region. 



2. The basic spawning grounds of the summer herring are along the southern, western and 

 south-eastern coasts of Iceland and are distributed along the slopes of the continental plateau, in 

 the zone of the warm waters of Irminger current . This is confirmed by the distribution of the 

 early stages of larvae (less than 10 mm. in length) and also by the departure of the summer herring 

 from the northern Iceland regions during its spawning period. PINRO investigations in 1954 (Yuda- 

 nov) revealed pre -spawning concentrations of summer herring in the region to the north of the 

 Faroes. The most important spawning grounds of the summer herring in the Iceland region are 

 known: in the south-east (Cape Stoksnes), in the south - in the region of Westmannaeyjar Island, 



in the region of Cape Reykjanes and also around Snaefellsnes peninsula . It is highly likely that 

 there are summer race spawning grounds in Faxafloui Fjord, Breida Bay and Isa Fjord. The larg- 

 est number of early stages of larvae has been found above depths of 30-40 m. and 100 110 m. 

 Apparently the basic spawning grounds are disposed in these depth zones . 



The spawning of the summer herring begins at the end of June and continues in July and 

 August . It is quite likely that in some regions spawning may occur in the first half of September . 

 Spawning occurs at a temperature of 8° -9. 5° in a salinity near to 35%. 







3. Taning's researches, especially in recent years (1939, 1946), show a drift of larvae in 

 a westerly direction along the south coast and further to the north along the western coast of the 

 island. It was in fact in the latter region that he found the largest larvae - 18-25 mm. in length. 



One may assume that a large part of the young remains in the relatively shallow bays of the 

 west coast, where the warm waters of the Irminger current penetrate. 



Tlie western shores of Iceland are the regions where the younger age categories fatten. 

 There, in the region of Cape Reykjanes, Fridriksson discovered wintering young of the summer 

 race. In Faxafloui Fjord, numbers of fat, sexually immature herring were observed. 



4. A fundamental difference in the age composition of the summer herring of the northern 

 regions and the southern regions, namely the predominance of the older stages in the north and the 

 younger in the south, leads to the conclusion that their respective areas of distribution are some- 

 what dissociated. The northern shores of the island are frequented principally by the older age 

 groups, the younger ones keeping to the southern regions. 



The plan of the feeding migration of the summer herring appears as follows . After winter- 

 ing, which takes place in the southern regions of the island, the summer herring at the beginning 



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