FISHERY BULLETIN: VOL. 80, NO. 4 



on 

 _J 

 < 



O 



Q 



40-i 



30- 



20- 



10 







110- 



100- 



90 



80- 



70 



60 



1979 



n= 126 



1,1 M I I I M I 



a 



UJ 50 

 CD 



5 



z 



40 

 SO 



20 

 I 0- 



1980 



n= 511 



20 



25 30 



FORK LENGTH (cm) 



-M-M- 



-i — i — i — i — i 



Figure 8.— Length-frequency subsamples from trawl caught 

 Calamus leucosteus landed in South Carolina offshore trawl 

 fishery, 1979 and 1980. 



DISCUSSION 



The time of annulus formation is similar in 

 otoliths and scales, it occurs when water temper- 

 atures are warm, photoperiod is long, and, in 

 mature fish, just after spawining. The annulus 

 is formed later in the year (June-July) than in 

 some other reef species: vermilion snapper, 

 Rhomboplites aurorubens, March-May (Grimes 

 1978); black sea bass, Centropristis striata, 

 March-June (Mercer 1978); red porgy, Pagrus 

 pagrus, March-April (Manooch and Huntsman 

 1977). 



Twelve age groups could be identified using 

 otoliths, whereas only nine were determined 

 from scales because of the inability to read those 

 of older fish. In addition, some older fish aged 

 with otoliths had one or more rings than scales. 

 As a result, larger fish aged by scales appear 

 younger than those aged by otoliths, and this is 

 reflected in back-calculated and theoretical 

 lengths at age. The relationship of fork length 

 to otolith radius appears to be curvilinear. The 

 measurement of otolith radius used in this study 

 is actually a measurement of otolith thickness. 

 Beamish (1979) noted in the Pacific hake, Merluc- 

 cius productus, that growth of all parts of the 

 otolith was not identical throughout the 1 ife of the 

 fish. He found that growth of older otoliths con- 



tinues, but that increases in thickness, especially 

 in the ventral interior portion, becomes propor- 

 tionally more important than increases in otolith 

 length or height. Calamus leucosteus appears to 

 be best aged, using this measurement from sec- 

 tioned otoliths. 



Estimates of L^ = 331 mm FL for otoliths and 

 362 mm FL for scales appear low since a maxi- 

 mum size of 18 in TL (391 mm FL) was reported 

 by Jordan and Gilbert (1884) and we observed a 

 407 mm FL fish. The calculation of L x depends 

 on the number of age groups present and the dis- 

 tribution of individuals within each group. 

 Higher values of L x should have been expected if 

 a larger number of bigger older fish could have 

 been aged and included in the calculations. Com- 

 parison of growth coefficients (scales: K = 0.2Gll; 

 otoliths: K = 0.1731) indicates that C. leucosteus 

 attains maximum size at a rate similar to Centro- 

 pristis striata, K = 0.219 (Mercer 1978), Pagrus 

 pagrus, K = 0.096 (Manooch and Huntsman 1977), 

 Rhomboplites aurorubens, K = 0.198 (Grimes 

 1978), and red grouper, Epinephelus morio, K- 

 0.179 (Moe 1969). 



Calamus leucosteus spawns from April 

 through August, with peak spawning in May. 

 Both sexes may mature at age 1 and fecundity 

 estimates range from 30,400 to 1,587,400 eggs. 

 Pagrus pagrus, another commercially important 

 sparid occupying the same range, spawns from 

 January through April, matures at age 2, and 

 has fecundity estimates ranging from 48,660 to 

 488,600 eggs (Manooch 1976). 



Calamus leucosteus, as well as several western 

 Atlantic sparids (Reinboth 1970; Manooch 1976; 

 Roumillat pers. obs.), demonstrates protogynous 

 hermaphroditism, which can only be determined 

 by histological observations. Sexual transition 

 in C. leucosteus involves the rapid proliferation 

 of testicular tissue in the posteroventral tunica of 

 the ovary which is the typical sparid protogynous 

 pattern (Smith 1975). The testes does not infil- 

 trate the ovarian lamellae as in groupers (Smith 

 1965), but envelops the regressing female tissue. 

 Male and female tissues are separated during 

 transition by connective tissue, but the sperm 

 ducts pass within the ovarian wall. Other west- 

 ern Atlantic families that demonstrate protogy- 

 nous hermaphroditism in addition to the Spari- 

 dae are the Serranidae (Smith 1965, 1975), the 

 Labridae (Warner and Robertson 1978), and 

 Scaridae (Robertson and Warner 1978). The 

 labrids and scarids have complex socially in- 

 fluenced reproductive strategies that have not 



872 



