896 



Fishery Bulletin 9 7(4), 1 999 



Table 2 



Von Bertalanffy growth parameters for Coryphaena hippurus calculated by different methods. The standard errors of each pa- 

 rameter are in parentheses, n = number of specimens; L, = asymptotic length (cm FL); k = growth coefficient in l/yr; Rn = 

 goodness-of-fit index; r = correlation coefficient; = growth performance index. LFA is length-frequency analysis; S and O are 

 scale and otolith readings. 



Population 



Sample 



Method 



Rn 



<t> 



Juveniles 

 Juveniles 

 Females 



Males 



Whole 



1990 

 1991 

 1990-91 



1990-91 



1990-91 



LFA 

 LFA 

 SandO 



SandO 



SandO 



0.92 



0.91 



0.87 



4.118 

 4.146 

 4.277 



4.302 



4.300 



140 

 120 - 



"E 100 - 



o 



^ 80 

 -H 60 - 

 I 40 - 

 20 - 



0^ 



and Jones, 1992). According to 

 our results and those of Uchi- 

 yama et al. ( 1986 ), the deposition 

 of increments in otoliths begins 

 on the first day of life. In addi- 

 tion, ripe eggs hatch within 50- 

 60 hours after fertilization, de- 

 pending on temperature (Palko 

 et al., 1982). Thus, hatching dis- 

 tribution can be compared with 

 the spawning period of the spe- 

 cies in the area, which is known 

 from adult fish maturity data 

 (Massuti and Morales-Nin, 1995, 

 1997). The agreement between 

 these hatching dates and the 

 above-mentioned data supports 

 the daily ages determined from 

 otoliths of wild juvenile fish. 



Another independent verifica- 

 tion method uses link ft-equency 

 analysis. The modal progression in 

 juvenile catches showed a rapid 

 gi'owth rate, which is reflected by the almost double 

 increase in monthly mean length during the fishing 

 season fi-om late August to early December This rapid 

 growth is in accordance with results obtained in the 

 Mediterranean and other areas with reared specimens 

 (e.g. Hassler and Hogarth, 1977; Renones et al, 1992; 

 Ayari et al., 1995; Benetti et al., 1995b), and with the 

 estimates of growth rates between 3 and 10 cm per 

 month, obtained from modal progression analysis on 

 wild specimens in different areas (Wang, 1979; 

 Oxenford and Hunte, 1983; Murray 1985). 



Growth parameters obtained by the two different 

 methods used for the two population groups were 

 quite different owing to the different length ranges 



+ 



0.5 1 



Juvenile otoliths 

 - Whole 



— I 



1.5 2 



Age (years) 



Adult scales 

  Females 



2.5 3 



 Adult otoliths 

 Males 



3.5 



Figure 4 



Age-length relationships and von Bertalanffy growth curves obtained from scale 

 and otolith interpretation in Coryphaena hippurus adults and juveniles. 



considered. Nevertheless, similar results are ob- 

 tained with the growth performance index. These val- 

 ues are similar to those calculated from growth pa- 

 rameters reported from scales of annuli by Beardsley 

 ( 1967 ) and Rose and Hassler ( 1968), which were 4.27 

 and 4.19, respectively. Those calculated from growth 

 parameters obtained by daily growth increments 

 (Uchiyama et al., 1986) were slightly higher (4.52 

 for females and 4.63 for males), probably owing to 

 the above-mentioned underestimation of age in adult 

 fish with this method, the few adult specimens stud- 

 ied, and the effect of temperature on growth and 

 metabolism. Temperatures can also explain the 

 slower growth rate of C hippurus in the western 



