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• There exists a reasonably identifiable sustainable yield that, 

 properly controlled, ensures the renewability of the resource 



• 



Increasing fishing effort tends to reduce the average size and age 

 of the yield, although not necessarily the weight. 



Based upon these biological assumptions, the information requirements 

 outlined earlier are met in part through the following stock assessment 

 methods. All survey techniques must be carried out through the use of a 

 vessel, although catch and effort data are usually reported by the host 

 governments of fishing fleets; in each case the accuracy of conclusions 

 depends largely on the accuracy of the data, rather than the mathematical 

 models that have been developed to analyze that data. 



