FISHERY BULLETIN: VOL. 69, NO. 4 



Table 7. — Mean catch of Atlantic menhaden per vessel week, in metric 

 tons, Atlantic menhaden fishery. 



a Records not available. 



between 87 and 173 metric tons and averaged 

 132 tons, and from 1955 to 1968 fluctuated be- 

 tween 156 and 381 and averaged 239 tons. The 

 increased use of airplanes and other improve- 

 ments in fishing methods, rather than any in- 

 creases in the al)undance of menhaden, probably 

 were responsible for the large catches per vessel 

 week in the later years. 



While the catches per vessel week were lower 

 for ports in the South Atlantic area than for 

 ports in the Middle Atlantic, the variation be- 

 tween ports in each area was of about the same 

 magnitude (Table 8). In the South Atlantic 

 the figures for Southport and Fernandina Beach 

 were about ecjual to each other but higher than 

 for Beaufort. In the Middle Atlantic the catch 

 per ves.sel week usually was highest at Tuckerton. 



The monthly catch-per-vessel-week figures 

 were computed for each area, but they showed 

 no consistent trends or variation worth noting. 



NUMBER OF PURSE-SEINE SETS 



The number of purse-seine sets was estimated 

 from logbooks and reduction plant i-ecords by 

 the formula: 



S, 



L,(S^ U) 



where: 



St = number of estimated monthly 

 sets, 



Si = number of sets from logbooks, 



Li = number of days for which num- 

 ber of sets is known, 



Lt = total number of landings days 

 from plant records. 



Vessels at each port were stratified by months 

 and by loading capacity, on the assumi)tion that 

 the number of sets per day varied with both 

 lime and capacity. The number of monthly 

 sets was estimated for vessels in each stratum. 



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