Newman et a\ Variability in the population structure of Lutjanus adetii and L quinquelmeatus 



323 



Discussion 



The significant differential growth in length and 

 weight of both species among reefs and between sexes 

 indicates that rates of growth in terms of weight at 

 length of both species was variable at the spatial 

 scale of individual reefs. However, statistical and 

 visual comparisons of the VBGF for L. adetii indicate 

 that the pattern of growth in individuals among reefs 

 with increasing age was relatively similar. Because only 

 one gear type was used and the distribution of juvenile 

 L. adetii was not determined and is presently not 

 known, it was not possible to obtain a sufficient range 

 of sizes to describe the first few years of growth. The 

 growth patterns of L. quinquelineatus described by the 

 VBGF were significantly different among reefs. How- 

 ever, no significant differences were detected in the 



mean lengths of individuals in age classes 2-6 among 

 reefs (Table 6 ). These results indicate that initial growth 

 rates among reefs were not significantly different and 

 that the significant differences in the overall growth 

 rates among reefs probably reflected the number of 

 young fish available for capture at each reef. 



The necessary pooling of size-at-age data over two 

 different years may have biased the resulting growth 

 patterns, if growth was variable among years. There 

 was, however, no evidence to suggest that growth of 

 either species was variable among years. The pool- 

 ing of data over a number of years was necessary in 

 order to sample a wide cross section of age classes. 

 The inclusion of size-at-age data over a number of 

 years has the advantage of providing a general de- 

 scription of the growth patterns of each species at 

 each reef. However, large sample sizes covering a 



