Reproductive life of the Indian Mackerel Rastrelliger kanagurta (Cuvier 1817) in Uttara Kannada coast, Karnataka, West coast of India

Abstract

The investigation on the reproductive life of the Indian Mackerel, Rastrelliger kanagurta (Cuvier 1817) in the Uttara Kannada coast for a period of 13 months was performed from Jan 2018 to Jan 2019. A total of 1299 fishes were dissected for entire period and their biological parameters were investigated. Of these total fishes, 734 fishes were female, 435 were male and 130 were indeterminate. Throughout the year the fishery was present with copiousness in pre-monsoon and post-monsoon period .Significantly the length and total weight of Indian Mackerel, Rastrelliger kanagurta was found to be linear and the Pearson's correlation was 0.913 (p<0.005). (Bervian et al., 2006, Fontoura et al. 2010 found that mooting the fishes can change its growth pattern during its life span and many authors sign it a mark of reproductive intricacy. The total body weight, the gonad weight and the fecundity was at its peak in the monsoon period and the maximum length was observed in the pre monsoon period. By using cumulative frequency method Lm was found to be 16.65 cms for males and 17.85 for females in Indian mackerel Rastrelliger kanagurta. The intent of the present work is to built a relationship between length and weight in relation to the size of first maturity of Indian Mackerel Rastrelliger kanagurta also classifying of developmental stages of the gonads and predicting the GSI.