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SUMMARY
The scale studies indicate that the annulus is a reliable year mark. A linear relationship exists between anterior scale radius and body length so that back-calculations of length were possible. Males and females had a similar growth rate. The growth rate is similar to that found by Mulder (1973) for L. capensis in the Vaal River. Fish under 35 centimetres in length had a sex ratio of 1:1, but in larger fish, only 16 per cent were males. Males reach sexual maturity at a length of 15 to 25 centimetres and females at a length of 20 to 25 centimetres. The spawning season extends from September to March with a peak in November. Fecundity increased with an increase in length from 12 664 for a fish of 22.8 centimetres to 106 286 for a fish of 34.8 centimetres.
The results are basically similar to those found by Mulder (1973) in the Vaal River except for fecundity and length at sexual maturity.
