CONTRIBUTIONS TO THE 



LIFE HISTORY OF BLACK SEA BASS, CENTROPRISTIS STRIATA, 



OFF THE SOUTHEASTERN UNITED STATES 1 



Charles A. Wenner, William A. Roumillat, and C. Wayne Waltz 2 



ABSTRACT 



Ages of black sea bass, Centropristis striata, from the South Atlantic Bight were determined from otoliths. 

 Analysis of marginal increments showed that annulus formation occurred in April and May. The von 

 Bertalanffy growth equation derived from back-calculated mean standard lengths at age was It = 341 

 (1 - e -0-2309(f+o.30io)^ w jj ere £ j s a g e j n y ears an( j \f _ standard length at age. The oldest fish was age 



10. 



Centropristis striata is a protogynous hermaphrodite that undergoes sex succession at ages 1 through 

 8. The process of sex succession is described from histological examination of the gonads. The major 

 spawning period is from March to May, and a minor spawn occurs in September-October. Mature males 

 and females were encountered at age 1. Fecundity estimates ranged from 17,000 in a 108 mm SL female 

 to 1,050,000 in a 438 mm SL fish, and were significantly related to length, weight, and age. 



The instantaneous rate of total mortality of C. striata from catch curve analysis, ranged from 0.721 

 in 1978 to 1.320 in 1981 for commercial fish traps and 0.726 in 1979 to 1.430 in 1981 for hook-and-line 

 gear. Petersen mark-recapture techniques were used to determine the population size of C. striata on 

 two shallow-water patch reefs. Conversions of these estimates to densities gave 14-125 individuals per 

 hectare. 



The black sea bass, Centropristis striata (Linnaeus), 

 is an important recreational and commercial ser- 

 ranid (Huntsman 1976; Musick and Mercer 1977; 

 Low 1981) that occurs along the east coast of the 

 United States from Massachusetts to Florida, with 

 occasional individuals as far south as the Florida 

 Keys (Fischer 1978). Within this range, C. striata 

 is thought to form two populations separated at 

 Cape Hatteras (Mercer 1978). The northern popula- 

 tion migrates seasonally from shallow waters along 

 the Middle Atlantic and southern New England 

 coasts during summer to deeper water in the south- 

 ern part of the Middle Atlantic Bight during the 

 winter (Musick and Mercer 1977). Black sea bass in 

 the Middle Atlantic Bight are harvested commer- 

 cially with traps in shallow water during summer 

 and with otter trawl gear when aggregated in 

 deeper water in winter (Frame and Pearce 1973). 

 Commercial catches are almost exclusively from 

 traps in that part of the South Atlantic Bight from 

 Cape Fear, NC to Cape Canaveral, FL where fish- 

 ing is largely confined to patch reefs (live bottom 

 habitat of Struhsaker 1969 or inshore sponge-coral 



Contribution No. 205 from the South Carolina Marine Resources 

 Center, Marine Resources Research Institute. 



2 Marine Resources Research Institute, South Carolina Wildlife 

 and Marine Resources Department, P.O. Box 12559, Charleston, 

 SC 29412. 



habitat of Powles and Barans 1980) at depths from 

 20 to 46 m. South Carolina commercial landings 

 were as high as 350.7 metric tons (t) in 1970, but 

 show large annual fluctuations (Fig. 1). 



Both the northern and southern populations have 

 been aged by analyzing otoliths (Mercer 1978), with 

 nine age groups identified north of Cape Hatteras 

 and eight along the southeastern U.S. coast. How- 

 ever, sampling techniques could have biased the 

 findings on southern C. striata since fishes came 

 from commercial catches which are frequently culled 

 at sea (Mercer 1978). 



Black sea bass are protogynous hermaphrodites 

 (Lavenda 1949), wherein most individuals function 

 first as a female and later as a male. Most females 

 mature by age 2; older age classes are composed 

 predominately of male fish although sexually active 

 males are in all age groups. Sexual succession oc- 

 curs at ages 1 through 5 (Mercer 1978). The north- 

 ern population spawns from June to October with 

 peak reproduction in July and August off Virginia 

 (Mercer 1978). 



There is insufficient published information to 

 describe the life history of this valuable commercial 

 and recreational species in the South Atlantic Bight 

 in detail. This report describes aspects of the life 

 history of C. striata from the South Atlantic Bight, 

 including age and growth, sex ratios, size and age 



Manuscript accepted October 1985. 

 FISHERY BULLETIN: VOL. 84, NO. 3, 1986. 



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