508 
Fishery Bulletin 99(3) 
— •— Present study 
— O — Suda and Kume (1967), size frequency 
Yukinawa and Yabuta (1963), scales 
— is — Yukinawa and Yabuta (1963). size frequency 
— • — Shomura and Keala (1963), M, size frequency 
Figure 8 
Growth curves of Pacific bigeye tuna estimated by different 
authors. 
with the slow-growth period indicated by the narrow and 
translucent rings. Similar findings have been reported for 
skipjack tuna (Antoine et ah, 1983), bigeye tuna (Gaikov 
et ah, 1980), and swordfish (Ehrhardt, 1992; Tserpes and 
Tsimenides, 1995). Our efforts only partially validate fish 
age; complete validation requires either mark-recapture 
data or the study of known-age fish in the population 
(Beamish and McFarlane, 1983; Prince et ah, 1995; Tser- 
pes and Tsimenides, 1995). 
We estimated the parameters of the VBGF by using the 
Ford-Walford and nonlinear methods and found that the 
nonlinear method had a better fit (r 2 =0.95) than the Ford- 
Walford method (r 2 =0.91). Comparisons of our VBGF pa- 
rameters with previous studies (Fig. 8, Table 4) showed 
similar results to those of Yukinawa and Yabuta (1963) 
who used scales and to those of Suda and Kume (1967) 
who also used Pacific samples of bigeye tuna. The values of 
t 0 differed because different aging techniques were used. 
Following the suggestion of Gallucci and Quinn (1979), 
Vaughan and Kanciruk (1982), and Hanumara and Hoe- 
nig (1987) that Ford-Walford and other linear methods be 
replaced by nonlinear fitting techniques; we propose using 
parameters of VBGF estimated by the nonlinear method 
(Table 3) for description of age and growth for the western 
Pacific bigeye tuna. 
Acknowledgments 
We thank Pei-Ching Chiang who assisted in the field sam- 
pling at the fish market. We thank Sheng-Ping Wang 
who assisted in preparing some figures and tables. We 
also thank Clay E. Porch, Southeast Fisheries Sci- 
ence Center, National Marine Fisheries Service, and 
Chu-Fa Tsai, visiting professor at the Taiwan Endemic 
Species Research Institute, who reviewed the manu- 
script. We are indebted to three anonymous referees 
for their valuable comments and to John V. Merriner 
(scientific editor) and Sarah Shoffler (editorial assis- 
tant) for their editorial suggestions in revising the 
manuscript. 
Literature cited 
Alves, A., P. de Barros, and M. R. Pinho. 
1998. Age and growth of bigeye tuna Thunnus obesus 
captured in the Madeira Archipelago. Int. Comm. 
Conserv. Atl. Tunas, Coll. Vol. Sci. Pap., vol. 48(2): 
277-283. 
Antoine, L. M., J. Mendoza, and P. M. Cayre. 
1983. Progress of age and growth assessment of Atlan- 
tic skipjack tuna, Euthynnus pelamis , from dorsal fin 
spines. In Proceedings of the international workshop 
on age determination of oceanic pelagic fishes: tunas, 
billfishes, and sharks (E. D. Prince, and L. M. Pulos, 
eds.), p. 91-97. U.S. Dep. Commer., NOAA Tech. Rep. 
NMFS 8. 
Beamish, R. J., and G. S. McFarlane. 
1983. The forgotten requirement for age validation 
in fisheries biology. Trans. Am. Fish. Soc. 112:735- 
743. 
Calkins, T. P. 
1980. Synopsis of biological data on the bigeye tuna, Thun- 
nus obesus (Lowe, 1839), in the Pacific Ocean. In Syn- 
opses of biological data on eight species of scombrids (W. 
H. Bayliff, ed.), p. 219-259. Inter-Am. Trop. Tuna Comm. 
Spec. Rep. 2. 
Cayre, P. M., and T. Diouf. 
1983. Estimating age and growth of little tunny, Euthynnus 
alletteratus, off the coast of Senegal, using dorsal fin spine 
sections. In Proceedings of the international workshop 
on age determination of oceanic pelagic fishes: tunas, bill- 
fishes, and sharks (E. D. Prince, and L. M. Pulos, eds.), p. 
105-110. U.S. Dep. Commer., NOAA Tech. Rep. NMFS 8. 
Chen, Y., D. A. Jackson, and H. H. Harvey. 
1992. A comparison of von Bertalanffy and polynomial func- 
tions in modelling fish growth data. Can. J. Fish. Aquat. 
Sci. 49:1128-1235. 
Compean-Jimenez, G., and F. X. Bard. 
1983. Growth increments on dorsal spines of eastern Atlan- 
tic bluefin tuna, Thunnus thynnus , and their possible 
relation to migration patterns. In Proceedings of the 
international workshop on age determination of oceanic 
pelagic fishes: tunas, billfishes, and sharks (E. D. Prince, 
and L. M. Pulos, eds.), p. 77-86. U.S. Dep. Commer., 
NOAA Tech. Rep. NMFS 8. 
Delgado de Molina, A., and J. C. Santana. 
1986. Estimacion de edad y crescimiento del patudo (Thun- 
nus obesus , Lowe 1839) capturado en las Islas Canarias. 
Int. Comm. Conserv. Atl. Tunas, Coll. Vol. Sci. Pap., vol. 
25:130-137. 
Draganik, B., and W. Pelczarski. 
1984. Growth and age of bigeye and yellowfin tuna in the 
central Atlantic as far data gathered by RW “Wieczno”. 
Int. Comm. Conserv. Atl. Tunas, Coll. Vol. Sci. Pap., vol. 
20( 1 ):96— 103. 
