FISHERY BULLETIN: VOL 86, NO 1 



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Louisiana 

 Dec 1980 



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Louisiana 

 Feb 1981 



Florida 

 Dec 1980 

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Texas 

 Feb 1981 



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60 



ESTIMATED AGE (days) 



Figure 6.— Growth of larval gulf menhaden collected in the winter 1980-81 in the northern Gulf of Mexico. The Gompertz growth 

 model was used to describe the data. Coincident data points are labelled as in Figure 4. 



statistical difference in growth of larvae caught 

 off Texas in February 1981 and 1982, and it ap- 

 pears that the 1982 larvae grew at a faster rate. 

 Conclusions from these statistical differences in- 

 volving TX February 1981 larvae collections 

 should be viewed with caution because of the rel- 

 atively poor fit (r^ = 0.526) of the model. Inade- 

 quacies, such as the lack of larvae <13 or >31 

 days old, in that data set probably resulted in the 

 relatively poor parameter estimates (Table 2). 

 Additional sampling would be necessary to fur- 

 ther test the hypotheses of differences in growth 

 between geographic areas in the northern Gulf of 

 Mexico and between years for Texas larvae. 



84 



Estimated Spawning Times 



Gulf menhaden larvae observed in this study 

 were estimated to have been spawned from mid- 

 October to mid-February (Fig. 8). The limited ex- 

 tent of seasonal sampling precluded estimation of 

 the probable total range of the spawning season. 

 Most larvae captured in December and February 

 had been spawned in November and January re- 

 spectively (Fig. 8). The considerable overlap in 

 spawning times of larvae caught the same month 

 in different years is a reflection of the similarity 

 of sampling dates. The relatively narrow distribu- 

 tion of spawning dates for larvae caught off Flor- 



