Some biology aspects of Indian Scad (Decapterus russelli, Rupell, 1928) in Pemangkat Fisheries Port, West Kalimantan

Abstract Absrtact. Indian Scad (Decapterus russelli, Rupell, 1928) is one of small pelagic fish that have important values in the south of China Sea. The objective of the study was to investigate some biology aspects of Indian scad caught by purse seine in the south of China Sea. The research was conducted from March to August 2014. This study used 395 fish samples with size between 14.1-21.9 cmFL (average 18.9 cmFL) and the sex ratio between female and male was 1:1.09. The growth patterns of Indian scad for male and female were positive allometric expressed by the following equation: W=0.0093L3.1309 (R2=0.8719) for male and W=0.0094L3.1359 (R2=0.8576) for female. The condition factors were about 0.25-6.22. Indian scads observed ranged between Maturity stage I and maturity stage V with GI for male and female were 0.056–6.36 % and 0.09 – 6.35 %, respectively. The Von Bertalanffy Growth Equation of Indian scad in the South of China Sea was Lt = 23.60 (1 - e 0.6(t+-0.2789)) with the length of infinity (L∞)=23.60 cmFL, coefficient of growth (K) = 0.6 year-1 and the theoretical age (t0) Indian scad that was equal to (t0) = - 0.2789.