Journal of the Marine Biological Association of India

Age and growth of the fishes of the genus Chirocentrus Cuvier.

Volume 27 Issue 1&2

G. Luther

Abstract

Sexual difference in the rate of linear growth, female growing faster than male, was observed in the fishes of the genus Chirocentrus, namely, C. nudus and C. dorab. These two species form a fishery around the Rameswaram Island. The following results relate to C. nudus which has been studied in some detail. A close agreement has been found between the average lengths of fish calculated by length frequency method and by back-calculation of the lengths to the successive hyaline zones in the otoliths. The respective lengths to caudal fork (LCF) in cm at completion of 1-13 years of age, as derived from the von Bertalanflfy growth equation, those of male being given in parenthesis are : 16.0 (17.5), 26.5 (25.0), 35.5 (31.5), 44.0 (37.0). 51.0 (41.5), 57.0 (46.0), 62.0 (50.0), 66.5 (53.5), 70.5 (56.5), 74.0 (59.5), 77.0 (62.0), 79.5 (64.5) and 82.0 (66.0). Fish of 4-6 years of age, which are well past the size at first maturity in both sexes, form bulk of the catches in the drift net fisherya round the Island. Consistent and significant difference in the size at first maturity between sexes as well as in the sex ratios in the broad length groups, or between juveniles and adults have been found to serve as a good indication for the existence of sexual difference in the rate of linear growth.

Date : 31-12-1985