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 PART III 



ASSESSMENT CAPABILITIES AND NEEDS 



I. ASSESSMENT TOOLS 



Tools Used on the Vessel 



As assessments depend primarily upon observations of the marine 

 ecosystem, the tools utilized to provide those observations must be 

 examined. 



As outlined in Part I of this report, survey information is developed 

 through the use of selected survey tows with small -meshed nets, although 

 abundance estimates for use by industry must be developed with gear 

 utilized by industry (nets using regulated mesh sizes). Such tows are 

 traditionally made on the basis of stratified random sampling, wherein 

 several locations are sampled at different times of the year, with efforts 

 made to remove as much bias as possible. 



Samples from the tows are then examined, measured, weighed, and 

 aged. Models predicting abundance on the basis of yield from such tows 

 are well -developed and sophisticated, requiring extensive laboratory 

 work and analysis before compilation. 



Environmental evidence is developed through temperature and salinity 

 sampling, using sounders that are dropped at selected areas and then 

 retrieved. Studies of currents and weather patterns are also made. 



All of these tools are utilized to develop data that is then analyzed 

 through the use of models. Statistical theory is well -developed and, 

 given good data, one can expect good results. 



Almost all of this data, however, must be gained through use of a 

 vessel. It should be noted that such data does not serve to predict 

 man's effects on the marine environment— catch and effort figures provide 



