Dentzau and Chittenden Population dynamics of Polydactylus octonemus in the Gulf of Mexico 



453 



Weight, girth, and length relationships 



Total weight-total length regressions for males and 

 females (Table 5) were not significantly different in 

 slope (F = 2.91, df = 1, 798), but they differed in eleva- 

 tion (F= 7.73, df = 1, 799). Therefore, equations are 

 presented for each sex and for males and females 

 pooled. Total weight-total length regressions for all 

 fish and for males and females pooled were significantly 

 different in slope (F = 99.10, df = 1, 2056); however, the 



one equation that pools all fish may be useful at this 

 stage of management. 



Discussion 



Spawning periodicity 



The primary winter-spring spawning period we found 

 for Polydactylus octonemus in the northwestern Gulf, 



