Wyanski et al : Growth, population age structure, and aspects of the reproductive biology of Epinephelus niveatus 



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per caught with longHnes in 1993-94. Comparisons 

 of age-length keys based on all specimens and speci- 

 mens for which there was a difference of 0-1 incre- 

 ments between readers revealed a strong similarity in 

 age distribution for 20 intervals (P>0.00256; Table 6). 



Slightly less initial agreement was noted when our 

 age estimates were compared with those of Waltz'* 

 for specimens caught in 1982-85 with longlines and 

 Kali poles. Ages were assigned to 85.3%^ of 129 speci- 

 mens that were examined in both studies. The same 

 age was assigned to 18. 2% of the specimens and 

 there was a difference of 0-1 increments between 

 studies for 40.0% of the specimens. Although the 

 percent agreement was low, the estimates of mean 

 size at age were similar (Fig. 5). Age distributions 

 in the five length intervals that could be tested were 

 similar (P>0.01021; Table 6). Given the similarity of 

 age distributions, we decided to use the age data of 

 Waltz^ for snowy grouper caught with snapper reels 

 in 1979-85 without reexamining the otoliths. 



The low initial agreement between readers was due 

 to a lack of a readily discernible growth pattern in 

 many otoliths. Typical abnormalities included crys- 

 talline areas that obscured increments (Fig. 6A) and 

 rounded opaque deformities that distorted increment 

 spacing ( Fig. 6B ). In addition, the axis of otolith growth 

 frequently changed direction at least once after 6-7 



increments (Fig. 6C). Despite our inability to make 

 linear measurements for back calculations, counts 

 of increments were usually possible, although easily 

 intei-preted otoliths (Fig. 6D) were the exception. 



We attempted to identify the first annulus 1) by 

 examining daily increment structure in the sagittae 

 of three specimens that were most likely YOY, and 



