Table 1. — Mean of counts on known age sagittae of Coryphaena 



hippurus. 



Table 2.— Mean counts on known age sagittae of Coryphaena 



equiselis. 



(Table 2) were plotted against corresponding known 

 ages (Figs. 2, 3). The relationships of mean incre- 

 ment counts (7) to known age (X) were Y = -0.5295 

 + 1.0035X(r = 0.999, P < 0.01) for 10 C. hippurus 

 and Y = -0.6986 + 1.0164X(r = 0.997, P < 0.01) 

 for 13 C. equiselis. These results demonstrated that 

 growth increments are formed daily, and validated 

 their use for aging wild fish up to 191 d for C. hip- 

 purus and 63 d for C. equiselis. 



Growth of Wild Specimens 



Because of sexual dimorphism, separate von Ber- 

 talanffy growth parameters were calculated for male 



and female C. hippurus (Table 3). The male and 

 female von Bertalanffy growth curves and 18 age- 

 length relationships of C. hippurus are shown in 



Table 3.— Von Bertalanffy growth parameters calculated from cap- 

 tured wild specimens of Coryphaena hippurus. 



Sex 



Number Parameter 



Estimate 



SE 



Male 



Female 



10 



200 





DAYS 



Figure 2— Validation of daily increments on sagittae of Cory- 

 phaena hippurus by relationship of known age (X) to mean incre- 

 ment count (Y) up to 191 d (r = 0.999). 



FIGURE 3— Validation of daily increments on sagittae of Cory- 

 phaena equiselis by relationship of known age (X) to mean incre- 

 ment count (Y) up to 63 d (r = 0.997). 



189 



