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Fishery Bulletin 94(2). 1996 



year classes or because there were age-varying mor- 

 tality rates (Fig. 7). The estimates of total mortality 

 rate, Z, ofL. quinquelineatus at LO and MR were 0.153 

 (fish aged 4-22 years, /~=0.711, SE=0.0245) and 0.335 

 (fish aged 5-16 years, ^=0.661, SE=0.0703), represent- 

 ing an annual survivorship of approximately 86% and 

 72% , respectively. Mortality rates ofL. quinquelineatus 

 between LO and MR reefs were significantly different 

 (homogeneity of slopes test, P<0.01). Figure 7 shows 

 that mortality rates and hence survivorship of L. 

 quinquelineatus among reefs is highly variable. 



A comparison of mortality rates among successive 

 years (with a relatively large sample size) could be 

 determined only for L. quinquelineatus at LO. The 



total rate of mortality, Z, of L. quinquelineatus at 

 LO in 1992 was 0.176 (fish aged 4-17 years, r 2 =0.615, 

 SE=0.0402, n = 109), representing an annual survi- 

 vorship of approximately 84% (Fig. 8), whereas the 

 total rate of mortality, Z, ofL. quinquelineatus at 

 LO in 1993 was 0.155 (fish aged 3-14 years, /- 2 =0.409, 

 SE=0.0621, n =64), representing an annual survivor- 

 ship of approximately 869r (Fig. 8). The mortality 

 rates ofL. quinquelineatus at LO were not signifi- 

 cantly different between successive years (homoge- 

 neity of slopes test, P>0. 05; Fig. 8). The natural mor- 

 tality rate, M, of both species among reefs is consid- 

 ered equal to total mortality owing to the negligible 

 amount of fishing mortality. 



