ATLANTIC MENHADEN PURSE-SEINE FISHERY 



-Estimated number of purse-seine sets in the Atlantic menhaden fishery, by year, month, and area. 



abundance, declined drastically in the Middle 

 Atlantic area in 1963, the mean tons per set also 

 declined. But in the North Atlantic area, where 

 the catch per vessel week also dropped sharply 

 in 1963, the mean tons per set did not drop until 

 1965. Where the decline in the catch per vessel 

 week was not so severe, no changes in the catch 

 per set were noted. Perhaps population density 

 must reach a rather low level before it can cause 

 a significant decrease in school size. A factor 

 which may contribute to an ostensible decrease 



in school size is selectivity by vessel captains, who 

 have a tendency to pass by the smaller schools 

 when fish are abundant. When fish are scarce, 

 captains are less discriminate. 



VARIATION IN ABUNDANCE 



Atlantic menhaden are pelagic, but they rarely 

 range far from shore. Most are caught within 

 20 miles of the coast. People have speculated 

 that a large population, unavailable to the fishery, 



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