FISHERY BULLETIN: VOL 85, NO. 3 



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NUMBER OF EGGS IN TRILLIONS 



Figure 12. — Numbers of Atlantic menhaden recruits (R) in millions plotted against esti- 

 mated egg production IP) in trillions for year classes 1955-1978. Curve a represents the 

 fitted Beverton and Holt function, R = 1/(0.00019 + 0.00027/P). Curve b represents the 

 fitted Ricker function, R = 325..35 P exp (-0.0158 P). 



Table 8. — Estimates of Atlantic menhaden population size and catch in numbers 

 in thousands (age 1 to maximum observed age), population exploitation rates, 

 population F. and catch in thousands of metric tons, by year. 



remained slightly below the MSY value (Fig. 13). 

 Catch and F^^^ values were also fitted to a mod- 

 ified version of the Pella-Tomlinson (1969) model, 

 which compensates for nonequilibrium conditions 



(PRODFITXFox 1975), assuming two significant 

 year classes. This technique resulted in an MSY 

 estimate of 557,000 t at Fpop = 0.336 (Fig. 13). 

 The scatter plot of yield/Fpn^ contains three 



pop 



586 



