one wished to accept theirio The sailing vessels fished as a rule 

 farther out to sea than they do now because they could find a 

 market only for the larger plaicej, which were to be found in 

 deeper water© Only when the larger fish were reduced by over- 

 fishing and when insufficient plaice were brought to market was 

 it profitable to bring in smaller plaiceo The same thing happened 

 with haddocko After the landing of small fish had started, it 

 increased as soon as new uses were found for them in fish fry 

 shops and the fish-meal industry* 



Since an increase of fishing intensity means that the larger 

 fish are caught before the smaller fish are seriously pursued^ 

 it is impossible to retain the production of marketable fish 

 solely by protecting the non=marke table fisho Suppose that in 

 fishing a stock of large density the only limitation imposed is 

 that fish below a certain minimum size are not to be caughto 

 At first, more and more ships will be attracted by 'the large 

 catcheso The density of the s took will decrease, the catch-per= 

 unit~of=time also will decrease, and attempts will be made to 

 keep landings high by increasing the fishing intensityo Eventually 

 the stock will reach such a low density that it will be impossible 

 to keep the catches at the original levels unless one catches 

 undersized fish, which is forbiddeno Finally, the fishing 

 becomes unprofitable and new areas will have to be sought or 

 ships will have to be laid up« Only a few ships will be able 

 to find employment by catching the fish which barely pass the 

 minimxim sizoo It is clear, therefore, that the fishing of this 

 stock was not organized in a rational way© The returns could 

 be higher if there were not a state of overfishingo Money and 

 energy were wasted by increasing the fleet, which led only to 

 a reduction of the income o 



A second reason for a necessary rationing is that a minimum 

 size reaches its full use only by a constant fishing intensity. 

 He have postulated on page 49 that the minimum size must be set 

 so that enough females mature to produce an amount of eggs large 

 enough to retain the fish stock at its optimum strengtho It 

 appeared that this biological lower limit increases with increase 

 ing fishing intensityo "ffe saw, for instance, that with a total 

 mortality of 50 percent, no haddock below 19 centimeters may be 

 caught if egg production is to be maintainedo Wien the total 

 mortality is 60 percent, none below 23 centimeters, and at fS 

 percent mortality, none below 27 centimeters may be caught© If 

 the fishing intensity is steadily increased, the minimum size 

 does not answer the biological demands any moroo The egg produc- 

 tion will decrease and the yoimger brood will be reduced* This 

 will happen although no tinders ized fish are destroyed by the 

 netSo A minimum size must therefore be combined with a limiting 

 of the fishing intensityo 



Theoretically the possibility of limiting the fishing intensity 

 exists by adopting a minimum size aloneo The minimum size must 

 then be placed so high that fishing is not profitable when the 

 optimum fishing intensity has been passed because insufficient 



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