86 NOEWEGIAN INVESTIGATIONS 



Both Dr. Hjort and the Danish biologist, Dr. C. G. J. Peter- 

 sen, were convinced in 1907 that ' in all proposals for preserving 

 the fish supply attention must be directed towards the protec- 

 tion of the older rather than the younger year classes '. They 

 argued that whether protected or no there will always be a large 

 number of young fish hatched out. Their conclusions seemed 

 to approximate to those of Garstang with regard to the plaice 

 when he argued that it is useless to look after the small adult 

 fish. It seems probable that they were rights The main prohlem 

 is to produce the greatest number of haddock of an age ivhen they 

 will fetch the best price. It is towards the solution of this 

 problem probably that science should address itself. For the 

 plaice Garstang's solution is transplantation. For the haddock, 

 so far as the writer is aware, no solution has been suggested. 

 Meanwhile Dr. Hjort and his colleagues have gone far towards 

 explaining the pre-war shortage — such as it was. 



They have shown in the course of their scale reading that 

 1904 and 1912 were years which produced an extraordinary 

 abundance of haddock fry— just as they did of herrings and 

 of cod. And they have shown good grounds for beheving this 

 abundance to be due to an unusual wealth of minute vegetable 

 food in the sea at the exact moment when the baby haddock 

 first began to feed. This theory is discussed in full on pp. 94-6 

 below in connexion with cod. It is here enough to point out 

 that the abundant hatch in 1904 may account for the increased 

 catch 1 in the North Sea in 1907, while that of 1912, which was 

 protected further by the minefields for four years, 7nay explain 

 the great numbers now being caught on all the grounds. Until 

 it can be shown that the present abundance is not due to 

 abnormally small infant mortality in certain years on the 

 spawning grounds, it would be rash in the extreme to ascribe 

 it (solely at any rate) to the ' closure ' during the war. 



See p. 81. 



