262 



Fishery Bulletin 102(2) 



250 



H 200 



150- 



100- 



50- 



Male 



Standard VB - method 1 

 Standard VB - method 2 

 Richards function - method 1 

 Richards function - method 2 



-5 -4 -3 -2 -1 



1 2 3 4 5 6 7 8 9 10 11 12 -5-4-3-2-1 



Age (year) 



9 10 11 12 



Figure 8 



Observed and back-calculated length-at-age and standard von Bertalanffy and Richards function model-predicted growth curves 

 for male and female sailfish <■!. platypterus) in the waters off eastern Taiwan. 



300 -i 



250 



200 



150 



100 - 



50 - 



-de Sylva (1957) -sexes combined' 



- Koto and Kodama (1 962) - sexes combined' 



- Farber (1981) - sexes combined* 



- Hedgepeth and Jolley (1 983) - male" 



- Hedgepeth and Jolley (1 983) - female' 



- Alvarado-C and Felix-U. (1998) - sexes combined 



- Present study - male 



- Present study - female 



6 7 8 

 Age (year) 



10 



12 13 



Figure 9 



A comparison of the growth curves for sailfish (/. platypterus) esti 

 by different authors. I  Data from Table 1 of Hedgepeth and Jolley 



mated 

 1983.1 



use in stock assessments of the sailfish popu- 

 lation in the western Pacific Ocean. 



Acknowledgments 



The authors express sincere gratitude to 

 Andre Punt, School of Aquatic and Fishery 

 Sciences. University of Washington, for his 

 valuable comments and comprehensive edit- 

 ing of the manuscript. This study was in 

 part supported financially by the "Fisheries 

 Agency, Council of Agriculture, Taiwan," 

 through grant 91AS-2.5.1-FK7) to Chi-Lu 

 Sun. 



Literature cited 



Even though the aging method used in the present study 

 is the same as that of Hedgepeth and Jolley (1983) and 

 Alvarado-Castillo and Felix-Uraga (1998), there are nev- 

 ertheless differences in the estimated length-at-age. This 

 difference could be due to spatial differences in growth, 

 the range of ages and sizes used in the analysis, or the 

 form of the growth model applied. The size range in the 

 present study is broader than those in previous studies and 

 the growth curve is based on the Richards function rather 

 than the standard VB function. Therefore, we believe that 

 our growth parameter estimates are more appropriate for 



Akaike. H. 



1969. Fitting autoregressive models for pre- 

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 247. 

 Alvarado-Castillo, R. M.. and R. Felix-Uraga. 



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 1998. Growth of Istiophorus platypterus (Pisces: Istiophori- 

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 Antoine, L. M.. J. J. Mendoza, and P. M. Cayre. 



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 Beamish, R. J., and D. A. Fournier. 



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