THE COD FISHERIES NEAR THE LOFFODEN ISLANDS. G47 



a better insight into the natural history of the herring. My investiga- 

 tions, made during my stay on board the Ilansteen, had led to a definite 

 result in this matter, whicli, at any rate, throws more light on the natu- 

 ral history of the herring. This result is of a purely negative eliarac- 

 ter, but nevertheless it is undoubtedly of great importance, as in con- 

 nection with the observations of the last two years it leads to a definite 

 and, as I think, more correct and more important opinion regarding the 

 nature and Migrations of the herring. 



As I have said above, it was quite a common opinion among modern 

 zoologists that the spring-herrings when not near the coast, therefore 

 during summer and autumn, live in the deep valleys or basins of the sea, 

 oft" that same coast where they spawn during winter and spring, an opin- 

 ion which I shared as fiir as the cod was concerned.* This opinion was 

 lirst advanced by Professor IsTilsson, and is chiefly based on the great 

 difference exhibited by tne various herrings found on the Swedish coast. 

 Also regarding our coast, similar views have been expressed, viz, that 

 the spring-herrings, when not near the coast, live in the great deep, 

 chiefly in the very deep trough, which, varying in breadth from ten to 

 fifteen Norwegian miles, extends along our western coast as far as Stat 

 and empties into the North Sea.t The results of the investigations of 

 the depths of the sea, which of late years have been carried on, on a large 

 scale, do not seem to contradict this opinion, since it has been shown 

 that even in the great deep there may be a rich and varied animal life, 

 so that the herring would find sufficient food all the year round even at 

 the greatest depth. These same investigations, however, have proved 

 that the nature of the deep is not the same everywhere, but that just 

 as on the dry land there are barren places with very little animal life — 

 submarine deserts — which are traversed by the greedy schools of fish, 

 but which could never be their permanent place of sojourn. This is 

 chiefly dependent on the nature of the bottom, and, to some extent, on 

 the varied depth. Where the nature of the bottom is such as to allow 

 the smallest animal to live and develop in any considerable quantity, 

 animals of a higher grade, which live on these, will make their appear- 

 ance, and from the same reason the place will become a convenient place 

 of sojourn for fish and other large marine animals. But where the con- 

 ditions are not favorable for the development of lower animals, the 

 higher animals {e. g., fish) cannot live. 



On account of this actual dependence of the various marine animals 

 on each other, it will be comparatively easy for a zoologist to decide 

 from the nature of the bottom whether it will be suitable as a perma- 

 nent place of sojourn for fish. The investigations made by me on board 

 the Hansteen during this and the preceding year have sufficiently 



* I have, however, as will be seeu from my second report, changed my opinion, as I 

 consider the large hanks olf the coast as the home of the winter-cod. 



tSee A. Boeck's work : " Om Silden og Sildefiskerierue'' (on the herring and the her- 

 ring fisheries), p. 47. 



