94 FISHERIES OF THE NORTH SEA 



distance it covers and of its numbers. Its 

 annual journey down the East Coast of 

 Britain has been a great source of profit to 

 the British and Dutch for hundreds of 

 years. In spring it is found off the North 

 of Scotland, where Stornoway is the centre 

 of operations. As the shoals move down, 

 the fleets work successively from Wick, 

 Peterhead, Fraserburgh, Shields, Scar- 

 borough, Grimsby, Yarmouth, and Lowes- 

 toft. Always the centre is moved south 

 as the season advances. The reasons for 

 this great annual movement are intimately 

 connected with feeding and breeding. The 

 great oceanic currents, the changing 

 temperatures of the waters, the presence 

 or absence of plankton, aie all factors in 

 the cause of the journey and the direction 

 it takes. 



The study of these inter-relating move- 

 ments would probably be amply repaid in 

 commercial profit, for a proper knowledge of 

 the dependence of migrations on currents 

 and temperatures may perhaps point out 

 new routes and fishing grounds at present 

 unknown. As the industry gains in im- 

 portance, the fisheries will extend farther 



