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V. COMPLEXITIES 



There are two immediate and significant complexities that must be 

 addressed by stock assessment: 



The ocean represents an integrated and dynamic ecosystem that 

 operates according to little-understood variables. 



Much of assessment must be based on analysis of fishing impacts on 

 that ecosystem. Such impacts are difficult to calculate, particularly 

 when their data are based on reported information. 



These two complexities shall be treated in turn. 



1 . The Ocean 



Easily overlooked in the face of rapid stock depletions 

 there exist several problems implicit in a study of ocean resources. 



First, the ocean within which fisheries resources are found is vast. 

 Georges Bank alone represents several thousand square miles. 



The marine ecosystem is distributed in three dimensions, not two as 

 are most agricultural resources. 



Within this vast area, or volume of water, exist the fish populations 

 of the sea. 



Such populations are of many different species and at least require: 



• Food 



• Breeding Areas 



• Ability to occupy a certain volume of water 



Plankton and phytoplankton, like plants on the land, require oxygen, 

 carbon dioxide and light to survive. They thus concentrate in the light- 



