Length Frequency Analysis of Indian Mackerel, Rastrelliger Kanagurta (Cuvier,1817) Off Ratngiri Coast, Maharashtra, India

Abstract

A study on length frequency distribution of Rastrelliger kanagurta along Ratnagiri coast, Maharashtra showed that, random samples of fish collected from the commercial catches were ranged from 4. 6 to 29. 9 cm of total length mainly clustering between size groups 10-12 cm, 13-15 cm, 16-18 cm, 19-21 cm, 22-24, 25-27 cm and 28-30. It was observed that modal group of 22-24 cm size fish caught during March 2011 to Feb 2012. Shifting of the modes to next modal class was evident from the ELEFA -II analysis. The analysis showed a curve indicating the broods or spawning periods. The recruitment was observed in April (Projected values). From the cumulative frequency calculations, it was observed that R. kanagurta attained first maturity in in first year. It attains 20. 15 cm, 27. 6 cm and 30. 5 cm at the completion of 1st , 2nd and 3rd years, respectively. The asymptotic length (L") obtained in the present study was 31. 8 cm.