_ 35 — JOH. HJORT ANT) C. G. JOH. PETERSEN 



south and west coast of the island as is shown in the Chart (PI. X). This distribution of 

 the pelagic young cod in June agrees, as the Chart shows, with the distribution of the coastal 

 water containing a salinity of about 35 ''/oo and a temperature of over 5° C. ^ In July, many 

 already began to seek the bottom and were found there on the south coast e. g. in depths of 

 47 — 72 m. Very many however, still remain pelagic and can be fished, e. g. in July, along the 

 north coast of Iceland. In August, the most have sought the bottom here, where they are to 

 be found in the fjords in enormous quantities. In agreement with the hydrographical conditions 

 in the Icelandic waters, the young cod are not however, carried away from the coast into the 

 open sea, but move with the great coastal current in the direction from the south to the 

 west coast, from there round Cape North to the north coast, and towards the end of August 

 they begin to appear even on the east coast of Iceland and in September in the fjords there. 

 It is therefore interesting, that practically no cod are spawned on tliis east coast nor on the 

 north coast and that, for example, no cod of the same year occur in July. This was 

 proved by numerous hauls at all depths, pelagic as well as on the bottom. Thus, whilst no 

 cod of the same year (the 0-group) occurred in the fjords of the east coast in July, over 12,000 

 cod of the previous year (the I-group) were taken in only 6 hauls on the 23rd of July. From 

 September onwards, the 0-group is found in increasiog numbers and at the beginning of the 

 following year, they are on the east coast, where none are born, perhaps in greater quantities 

 than anywhere on the coasts of Iceland. 



During 1903 and 1904, extensive investigations were made in the North Sea by the various 

 investigating steamers. Search was made for the young fish of the various gadoid species at 

 several hundred observation-stations over the entire region, on the bottom and in all depths of 

 water with large nets and flne-meshed trawls. It has thus been shown, that the young cod in 

 the North Sea give up the pelagic habit and seek the bottom at much younger stages than 

 happens in the Norwegian Sea. Only very few young cod of over 2 cm. in length were found 

 after the first of June, before that, however, they occurred in great quantities, especially in the 

 neighbourhood of the coasts. It appears that their distribution is determined from the begin- 

 ning by the fact, that they are born on the coastal banks and that the currents of the North 

 Sea also help to keep them at the coasts or to carry them there. In the great 

 northern part of the North Sea, there seems to be a relatively resting mass of water into which 

 they are not carried. Accordingly, if we investigate the first bottom-stages of the 0-group 

 with fine-meshed trawls, we find, as is well sJiown by the existing material, that they occur in 

 great quantities along the coasts, in the neighbourhood of the large estuaries, on the coastal 

 banks and on the more southerly banks as far as the Great Fisher Bank. Further north in 

 the deeper part of the North Sea, where the same temperature (6° — 7° C.) rules the whole 

 year round, they are not to be found or only in single examples. These conditions cannot be 

 carried further into detail, as the whole large material has not yet been completely worked out; 

 it may nevertheless be said, that the international investigations of the last two years have 

 attained the important result of determining the distribution of the 0-group in the North Sea 

 with certainty, whereby one of the most important conditions for understanding the natural 

 history of the cod has been fulfilled. 



> Schmidt, 1. c. p. 72—76. 



