Scales were used for the determination of age with back‐calculation of length. The oldest fish was VII + years old. Back‐calculation did not exhibit Lee's phenomenon. The most rapid growth occurred in summer at water temperatures over 25°C. The growth in weight was c. 331 g year‐1 after IV vears of life. Growth was well described by von Bertalanffy equation : ll ‐ 91·0 [l=0·122(l0·25)] The length‐weight relationship followed the cube law (b = 3·0601) Kn ranged from 0·74 to 1·18 with a mean value of 1·0. Spawning occurred in January, fecundity was 74 509 with a mean of 1157 eggs ‐1 body weight. Mean diameter of eggs was 1071 (pm). A developed ovary had ova of two sizes, immature oocytes and mature ova. The fish is a carnivorous feeder.
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