46 



approximately 74 percent of registered fishermen submitted 

 logbooks and renewed their exemption certificates. 



Observers placed by NMFS aboard fishing vessels provided 

 additional information on fishing effort, incidental takes of 

 marine mammals, and other details about fishing operations such 

 as time of day, depth and length of nets, and soak times. These 

 details enhance our understanding of why and how marine mammals 

 are taken so that methods can be developed for reducing 

 incidental takes. 



Observer data confirmed that numerous marine mammals were in 

 fact being taken during the operations of most Category I 

 fisheries, those with frequent removal of marine mammals. 

 However, at least three Category I fisheries, or specific 

 segments of these fisheries, were determined to have a minimal 

 impact on marine mammal populations and were subsequently 

 reclassified. 



In 1990, the verification of logbooks from eight Category I 

 fisheries indicated that approximately 80 percent of fishing days 

 in observer records were also reported by vessel owners. 

 Mortality of marine mammals reported by vessel owners ranged from 

 40 to more than 100 percent of that reported by observers. When 

 owner logbooks reported more deaths of marine mammals than 



