FISHERY BULLETIN; VOL. 87, NO. 1 



Estimates of specific and absolute growth rates 

 (Table 4) were calculated from length-at-age (L,) 

 for various ages as predicted by the Laird-Gompertz 

 equation 



5.26 exp[0.104/0.075 (1 - e 



-0.076( 



)]• 



Specific growth rate declined from 7.4% to 1.1% 

 per day SL at 30 days after hatching, before level- 

 ling off at around 0.5% per day SL over the latter 

 half of larval life. Absolute growth showed a similar 

 pattern, with a rapid decline from a maximum value 

 of 0.57 mm/d at day 5 to a value of approximately 

 0.1 mm/d approaching metamorphosis, 40-50 days 

 after hatching. 



Spawning occurred over three months (mid-July 

 to mid-October), peaking around the first week in 

 September (Fig. 5). There are indications of lunar 

 periodicity within those months; spawning peaks 

 were separated by approximately two weeks, ap- 

 parently associated with first and third quarter 

 moon phases. Time series analysis also indicated a 

 14 d periodicity in spawning peaks. Autocorrelation 

 coefficients larger than two standard errors of the 

 mean autocorrelation coefficient are considered sig- 

 nificant (fn. 5). Coefficients greater than this value 



Table 4.— Growth rates of Herklotsichthys castel- 

 naui larvae predicted from the Lalrd-Gompertz 

 growth equation at various times after hatching. 



(0.29) occurred on day (0.62) and day 14 (0.39), in- 

 dicating the existence of a periodicity in the data 

 of 14 days. 



DISCUSSION 



Clear growth increments consisting of alternating 

 light and dark bands were visible in all three pairs 

 of otoliths in Herklotsichthys castelnaui. Asterisci 

 and lapilli were formed, however, some time after 

 the sagittae. This suggested that the number of 



F 

 R 

 E 

 Q 

 U 

 E 

 N 

 C 

 Y 



n  378 



7/11 7/19 7/27 8/4 8/12 8/20 8/28 9/5 9/13 9/21 9/29 10/7 10/15 



DATE OF INITIAL INCREMENT FORMATION 



Figure 5.— Spawning periodicity of Herklotsichthys castelnaui based on back-calculated dates of initial increment 

 formation. Frequency values are 2 d class means, two increments being the maximum accepted error in increment 

 counts. 



80 



