FISHERY BULLETIN: VOL. 84, NO. 3 



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Figure 1.— Annual commercial landings of Centropristis striata in South Carolina. 



at maturity and sexual succession, and fecundity. 

 Additional information includes Petersen mark- 

 recapture estimates of standing crop on reefs, and 

 trends in the size and age composition with in- 

 creased exploitation. 



MATERIALS AND METHODS 



Age and Growth 



Most specimens were taken from the inshore 

 sponge-coral habitat between lat. 31.5° and 33.5°N 

 by commercial black sea bass traps (Rivers 1966), 

 Antillean-S traps (Powles and Barans 1980), hand- 

 lines, and trawl surveys from June 1978 through 

 September 1981. Supplemental specimens were 

 obtained from South Carolina commercial landings 

 and other research programs to determine season- 

 al gonadal condition and time of annulus forma- 

 tion. 



Centropristis striata were weighed to the nearest 

 g and total (TL) and standard (SL) lengths were 

 recorded to the nearest mm. Sagittae were removed 

 and stored dry in envelopes for subsequent age 

 determination. Unless damaged, the left sagitta was 

 placed concave side up in a dish of water over a dark 

 field and viewed at 12 x magnification using a binoc- 

 ular microscope. When viewed with reflected light, 

 sagittae displayed a central opaque field surrounded 

 by alternating translucent and opaque bands. The 



central field varied in size and shape from a small 

 opaque nucleus to a large opaque zone consisting of 

 one or more broken rings (Fig. 2A, B). Since ap- 

 parent daily growth rings have been observed on 

 both the sagitta and lapillus of C. striata (Johnson 3 ), 

 this zone was interpreted by counting rings from 

 the primordium to the edge of the central field. Oto- 

 liths were finely ground on both sides until the cen- 

 tral area of apparent daily rings could be observed 

 (Fig. 3A, B). They were then viewed with trans- 

 mitted light on a compound microscope at 500 x 

 and/or 1,000 x magnification. 



The intercept of the otolith radius-SL relationship 

 was used to derive mean back-calculated size at age 

 by the Fraser-Lee method (Poole 1961; Carlander 

 1982). The von Bertalanffy growth equation (Ber- 

 talanffy 1938) was fitted to mean back-calculated 

 SL at age using the SAS NLIN procedure (Helwig 

 and Council 1979) employing Marquardt's algorithm 

 and the SAS NLIN weight statement; mean back- 

 calculated lengths were weighted by the reciprocal 

 of the standard error of the mean squared. Both 

 standard least squares linear regression (Sokal 

 and Rohlf 1981) and geometric mean (GM) func- 

 tional regression analyses were used to describe 

 the relationship of length to length and length to 

 weight. 



3 G. David Johnson, Fish Division, U.S. National Museum, 

 Washington, D.C. 20560, pers. commun. April 1982. 



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