58 
Fishery Bulletin 95 ( 1 ), 1997 
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Figure 9 
Mean monthly (circles) and monthly (crosses) gonadosomatic indices for mature 
female and male Argyrosomus inodorus sampled in the southeastern Cape, April 
1990-January 1992. n=sample size. 
(rc=l,764) was significant (even at PcO.OOl), one of 
1.3:1 (n= 80) was not (Table 3). Thus researchers 
studying sex ratios should make every effort to ob- 
tain large samples, particularly if the chi-square 
method is to be used as a test for significant difference. 
Nursery areas 
Argysomus inodorus landed by the line fishery were 
mostly adult fish between 40 and 120 cm TL (Fig. 
12). Although fish <40 cm TL were not represented 
in the present study owing to the minimum size limit 
imposed on linefishermen, experimental linefishing 
indicated that silver kob on the linefishing grounds (reef 
substrata) were mostly >30 cm TL (Fig. 12) and that in 
the southeastern Cape and in the southern Cape they 
were generally larger than the female L 50 estimates. 
Argysomus inodorus trawled between Cape 
Agulhas and Port Alfred during SCBS’s (nonreef sub- 
strata) ranged between 5 and 120 cm TL but were 
generally <45 cm TL, and largely immature (Fig. 13). 
The modal length class increased from 20-25 cm at 
depths of 25-50 m, to 25—30 cm at 50-100 m and 
30-35 cm at 100-150 m; and the proportion of ma- 
ture fish increased accordingly. Although depths <25 
m were not sampled during SCBS’s, silver kob (iden- 
tified as “A. hololepidotus ”) trawled in <9 m during 
an earlier survey of the bays between Mossel Bay 
and Algoa Bay were mostly 9-18 cm TL (Smale, 
1984). Beckley ( 1984) recorded A. inodorus (also iden- 
