FISHERY BULLETIN: VOL. 69, NO. 4 



Table 11. — Mean number of purse-seine sets per vessel day in the Atlantic menhaden fishery, by year, month, and 

 area. Raw means are weighted, column means are unweighted. 



may occur far offshore. There is no available 

 evidence to support this view. 



There is evidence, however, that the entire 

 population is fished. Since 1945 Atlantic men- 

 haden have been exploited from northern Florida 

 to the Gulf of Maine, an area constituting nearly 

 their entire range. With the advent of airplanes 

 that could search larger areas and vessels that 



could range up to a hundred miles from port, 

 no areas have been unsearched or unfished, ex- 

 cept where prohibited by local restrictions. 



Under these conditions changes in the catch 

 per unit of effort are assumed to reflect changes 

 in actual, rather than aijjiarent, abundance. 

 Even though the figures have been influenced 

 by changes in vessel efficiency, they are sensitive 



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