FISHERY BULLETIN: VOL. 76, NO. 2 



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Figure 2.— The study site at Clayton's Rocks. 



RECRUITMENT AND GROWTH 



Di plod us sargus 



The monthly and total length-frequency dis- 

 tribution is given in Figure 3. The lumped sample 

 show^s a mode in the 10- to 20-mm size class, indi- 

 cating that larger fish tend to emigrate to deeper 

 water. The juveniles appear in the littoral zone 

 when between 9 and 10 mm standard length (SL), 

 and leave when about 90 mm long. It appears that 

 large fish utilize the intertidal area at high tide as 

 two fish of 107 and 108 mm SL were collected in 

 the intertidal area some 2 h after low tide and 

 another 164 mm long was collected 3 h after low 

 tide. 



Visibility was <15 cm in the pools of the re- 

 search area during September, October, and De- 

 cember due to flooding of the Fish River. No dives 

 could be made during this period in the subtidal 

 area with the result that fish >40 mm were not 

 collected. 



Recruitment of the juveniles into the littoral 

 appeared to be relatively constant as no monthly 

 peaks of abundance were found during the survey. 

 This tends to confirm Biden's (1954) suggestion 

 that females of this species spawn throughout the 

 year, though mainly in summer. 



No monthly modes could be followed over the 

 period of study as it is a continuously recruiting 



Standard Length (mm) 



Figure 3. — Monthly and total length- frequency distribution of 

 Diplodus sargus, showing three age-classes (O-t-, 1-I-, and 2 + ). 



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