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groundfish. Such catches are called by-catch, and a mount of by-catch be- 

 comes extremely important when such by-catches are of a depleted species. 

 A recent estimate has suggested that 38 percent of the total biomass 

 presently harvested on Georges Bank is achieved through by-catch. (■^^) 



Distortions likely in assessment of fishing activities as they relate 

 to stock sizes, the, result from the following variables: 



• Rapid changes in harvesting technology 



§ Noncompliance with management regulations 



• Intermittent and scattered gathering of necessary data 



• Outright falsification of necessary data 



• Problems with development of a catchability coefficient 



• Great difficulties in monitoring fishing activities 



It is within these variables that stock assessment science must operate. 

 Recognition of these variables has created sophisticated and specialized 

 probability forecasting models. In addition, political bargaining of common- 

 property resources has increased the pressures on assessment science, demand- 

 ing ever-more specific numbers as species have continually been depleted. 



Assessments seek to quantify information from an ecosystem that is: 



• Difficult to observe 



• Highly variable 



• Perturbed by fishing activities 



• Managed according to political rather than biological decisions. 



On the following pages the Georges Bank groundfishery in relation to 

 assessment will be examined. While not a history of assessment in the area. 



