Reproductive biology of the sawtooth barracuda, Sphyraena putnamae (Jordan and Seale, 1905) along the coastal waters of Karnataka, southeastern Arabian Sea

Abstract

The reproductive cycle, maturity, sex ratio, and fecundity of the sawtooth barracuda Sphyraena putnamae was investigated from 1108 specimen samples along the Karnataka coast off the southeastern Arabian Sea. The sex ratio between males and females (1:1.08) was not significantly different. The fork length at 50% maturity (Lm50) for females and males was estimated at 39.4 cm and 38.0 cm, respectively. The pattern of Gonadosomatic index (GSI) and the maturity stages of females suggest two peaks in the spawning, with a distinct one during April–May and a less prominent one between November–January.​ However, the incidence of spawning capable, regressing and regenerating fishes all through the year in varied frequencies implies that spawning takes place throughout the year. The absolute fecundity estimates vary from 69,689 eggs for a female of 30.4 cm fork length (FL) to 944,793 eggs for a female of 73 cm FL. The average batch fecundity was calculated as 310,763 hydrated oocytes per female. The relative batch fecundity ranges from (female gutted weight) 285 to 964 eggs g−1 with an average of 605 eggs g−1. Fecundity correlates positively with fish length and weight indicating that larger females produce a greater number of eggs compared with the smaller ones. The biological information on maturation, reproductive cycle, spawning periodicity and potential provided for the first time in this study can be useful for developing appropriate management strategies for the conservation and judicious exploitation of this commercially important barracuda species.