CHAPTER 2 



Conservation of Marine Resources 



A. T. Pruter 



The term ''conservation" as applied to a living resource, such as fish 

 or shellfish, has an entirely different meaning from that applied to a non- 

 living resource such as minerals or oil. The latter are nonrenewable. Man 

 must exploit them with reserve, recognizing that once used they cannot 

 be restored. 



In contrast, failure to use a living resource is to waste it. If not utihzed 

 by man, fish eventually die of old age or other natural causes. They are 

 continually being replaced by new individuals. As long as enough adult 

 fish are left to perpetuate the species, the surplus can be harvested. 



The generally accepted objective of conservation of a living aquatic 

 resource is to maintain the populations at levels which provide maximum 

 yields to man on a sustainable basis. This involves balancing removals by 

 man and losses from natural causes with additions to the populations 

 from recruitment of new individuals and their growth in weight. The 

 problem is complicated because populations differ in their rates of removal 

 and additions. Thus, conservation must be adapted to each population 

 according to its particular rate of recruitment, growth, and mortahty. 



Need For Conservation 



Soon after intensive fishing activities began in this country, it became 

 clear that man could over-exploit marine resources. Populations of Atlan- 

 tic and Pacific salmon have been decimated by man. Intensive sealing 

 activities twice brought the fur seal of the North Pacific to the verge of 

 extinction. As early as the 1920's it was evident that the Pacific haUbut 



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