Maturity, spawning and feeding intensity of cobia Rachycentron canadum (Linnaeus, 1766) in northwest coast of India
An attempt has been made to provide some vital aspects of reproductive biology of cobia Rachycentron canadum (Linnaeus, 1766). Samples for a period of two years from exploratory vessel and from the landing centers of Mumbai were used for the study. The average sex ratio between male and female observed was 1: 0.80. Dominance of number of female above the size of 100 cm was noticed. The size at first maturity of male and female was 72 and 83 cm respectively. Similarly, age at first maturity of male and female was estimated at 1.77 and 2.17 years respectively. Spawning season based on occurrence of five maturity stages and Gonadosomatic index (GSI) values indicated a throughout the year spawning behavior with peak spawning activity during July-August and November- January. Percentages of feeding condition of various maturity stages indicated that cobia take very less food during their spawning period. spawning period. The results obtained were compared with the results of similar studies round the world and elucidated.