102 



Fishery Bulletin 102(1) 



some suggestion that, like the GW-TW relationship, the 

 GSI-TW relationship varies between the island groups, 

 although to a much lesser extent (ANCOVA: df= 1,125; 

 F=7.44;P=0.007). 



o 



o 



There is some indication that larger fish spawn over 

 a longer period at the Palm Island group. During the 

 September-February spawning season, mean GSI values 

 were always higher for mature Palm Island group females 

 >230 mm FL compared with mature fe- 

 males <230 mm FL at the same location 

 (Fig. 10). This pattern is likely due in part 

 to the higher relative gonad weights of 

 larger fish (Fig. 9B) but also seems to be 

 driven by greater proportions of stage-IV 

 ovaries among larger mature females in 

 September, October, and February com- 

 pared with fish <230 mm FL (Fig. 10). 

 During these months, 13%, 13% and 25% 

 more large fish were at stage IV, respec- 

 tively, than were small fish. 



1 2 3 4 5 6 7 



B 



9 10 11 12 13 14 15 16 17 M 

 Age class (years) 



53 44 25 11 3 2 



1.0 

 0.8 

 0.6 

 0.4 

 0.2 

 0.0 



10 50 90 130 170 210 250 290 330 



Size class midpoint (mm fork length) 



Figure 6 



Proportion of mature female Lutjanus carponotatus and estimated age-spe- 

 cific (A) and size-specific (B) logistic maturation schedules at the Palm  

 solid lines) and Lizard (□, broken lines) island groups. Sample sizes for the 

 Palm (top value) and Lizard (lower value) Island groups are presented above 

 the data for each age or size class. Parameters of the maturity functions are 

 provided in Table 3. 



Discussion 



Demography and reproduction of 

 L. carponotatus 



Growth of L. carponotatus is rapid for the 

 first two years of life, slows over the next 

 two years, and nearly ceases by age 4. The 

 slowing and cessation of growth coincide 

 with the ages at 50% and 100% maturity, 

 respectively, and support the argument of 

 Day and Taylor (1997) that maturation 

 represents a pivotal physiological trans- 

 formation and consequently a fundamen- 

 tal shift in the growth trajectory. Further 

 supporting the idea that reproductive 

 development occurs at the expense of 

 somatic growth is the apparently longer 

 average spawning season among larger 

 fish that have ceased most somatic growth. 

 The limited growth over much of the lifes- 



