Age and growth of the marine carfish Tachysurus dussumieri (Val.) along the Dakshina Kannada coast

Abstract

Age and growth of the marine catfish, Tachysurus dussumieri along the Dakshina Kannada coast of Karnataka during March 1975 -May 1976 were studied using Petersen's and Bhattacharya's methods. The fish attains 230, 350, 471, 557, 613.6 and 662 mm respectively at the end of first to sixth year. Observations on vertebrae revealed formation of growth checks with in a short period and gradual decrease in growth rate with age. The length at formation of first growth check was 226.43 mm. Average back calculated lengths at formation of successive annual grovvth checks were 224.35, 357.01. 456.77. 553.59. 629.56. 692.05 and 770.90 mm. The Von Bertalanffy growth equation was L, = 1027 1027 [1-e-0.166(t+0.5)]. The life span of the fish was about seven years