288 FISHES AND MAN xi 



considered unsatisfactory by the fishermen, since the yield per unit of 

 effort is much greater when the richer stock is fished. 



The yield of haddock in the North Sea per day's absence averaged 

 5 -8 cwt between 1906 and 191 3, rose to 15-8 cvvt in 19 19, averaged 

 6-5 cvvt in 1 922-1 929, and 3-7 cwt in 1930-7. The fish are divided into 

 large, medium, and small categories, and the percentage of the last 

 category was 50 before the war, 70 in 1922-9, and 85 in 1930-7; 

 evidently the fish were becoming smaller throughout this period, yet 

 the total haddock catch changed only slightly, from 121 million kg 

 ( 1 910-13) to 138 million kg (1922-9) and 94 million kg (1930-6). 

 Fishing seems to have made the population consist of smaller fish, 

 giving a smaller yield per unit of fishing effort. This is a true index 

 of stock and its decline shows the extent of reduction. 



The figures available for plaice and cod taken from the North Sea 

 show much the same tendencies. Over a long period fishermen have 

 been afflicted by the consequences of the decline in yield per unit 

 effort indicated by such statistics. Already in the last century those 

 giving evidence before Royal Commissions expressed an uneasy feel- 

 ing that the profitability of the industry was declining. This situation 

 has been met by continual improvement in methods of fishing and the 

 exploitation of new grounds. The proportion of the total English 

 catch that is obtained from the nearer waters of the North Sea is now 

 much less than formerly, although the catch is no greater. We have 

 already seen that steam trawling and better gear all mean increased 

 labour for the crews, at greater distances from port. With all the 

 improvements in technique and discovery of new grounds we succeed 

 in obtaining from the sea little more fish than at the end of the last 

 century; and there is no greater profit for those engaged in the 

 industry. 



The 'Great Law of Fishing', as Graham calls it, 'that fisheries that 

 are unlimited become unprofitable' has been tested on at least three 

 occasions. During the two Great Wars the intensity of fishing in the 

 North Sea was reduced and thereafter both of the expected changes 

 were seen : (a) fishing became more profitable, (b) there were found to 

 be more old fishes in the stock. Perhaps more encouraging is a case 

 where the intensity of fishing has been regulated not by war but by 

 law. The halibut fishery of the Pacific coast of North America showed 

 the typical history of increasing effort and decreasing yield. Fishermen 

 went farther and farther afield in larger and more expensive boats, 

 setting ever more and more lines, but yet brought home the same or 

 a smaller amount of fish. Thus in 1907 there were 1,800,000 sets of 



