196 THE PRODUCTIVITY OF THE SEA [PART II 



either utterly sterile, or are productive to a very slight degree. 

 Such are desert-lands ; the higher rocky parts of mountainous 

 country ; the enormous tracts of land covered transitorily or 

 permanently by snow and ice ; and the relatively unproductive 

 moorlands. And even of the productive land surface only a very 

 small part is under cultivation. But everywhere in the sea, even 

 under the ice and in hot and cold areas, we find abundant life. 

 No part is sterile, and the variations in productivity are, when 

 compared with those on the land, of little account. If we take 

 equal average areas of land and sea, we will find that the yield 

 of the latter is greater than that of the former. Even the com- 

 paratively poor yield in fish per acre of the North Sea is probably 

 greater than the yield per acre of all the land in Great Britain 

 and Ireland. 



The impoverishment of the sea. We may regard that part 

 of the sea which is exploited by the fishing fleets of North Europe as 

 an uncultivated water area which bears annually a certain crop 

 of fish flesh. There are only very few spots along the shore 

 where the culture of shellfish is attempted and the product of 

 these cultivated sea-water areas is so small (relatively to the 

 total yield) that it may be neglected. At least 952,000 tons of 

 fish are taken annually from the North Sea, and about a million 

 and a half tons from the whole north-western fishing area. 

 This is the annual crop which the fishermen of North Europe 

 take from the sea. It is a " harvest of the sea " which does 

 not correspond to any sowing. 



Now the necessity for all fishery legislation is based on two 

 considerations : (1) that among a number of fishing vessels and 

 men working on a restricted fishing area, there must generally 

 be the possibilities of disorder, that is, fishermen belonging perhaps 

 to various nationalities, and perhaps practising different methods 

 of fishing, must at times interfere with each other, producing 

 disputes which may be productive of trouble, and not easy of 

 adjustment ; and (2) that since the quantity of useful fish products 

 that may be taken from the sea is limited, the time must come 

 when the produce of the fisheries will suffer impoverishment 

 merely because more fish are being captured than can be replaced 



