Journal of the Marine Biological Association of India

Reproductive biology of the Indian scad, Decapterus russelli (Ruppell, 1830) from Maharashtra waters, Northwest coast of India

Volume 57 Issue 1

Nalini Poojary*,L.R.Tiwari and Sujit Sundaram

10.6024/jmbai.2015.57.1.01792-11

Abstract

The length at which 50% of females of Decapterus russelli attain maturity was estimated at 153 mm. The presence of mature, ripe and spent gonads was observed from June to October and December to April indicating prolonged spawning season. The sex-ratio varied from 1:0.43 in 140-149 mm to 1:1 in 110-119 mm length groups. Month-wise distribution of sex-ratio indicated significant predominance of male at 5% in April, May and November. The absolute fecundity ranged from 29,986 to 1,52,123 eggs. Based on the GSI studies it is inferred that the species has a prolonged spawning season probably falling between December to March and June to October. The relative condition factor value was highest in January which indicates the peak spawning month. Length-wise condition factor of males and females were maximum in the length range of 100-229 mm. In the present study size of ova diameter ranged from 0.01 to 0.97 mm. The species seems to spawn twice in a season and the period between two spawning may not be a long one.

Keywords

Decapterus russelli, Maharashtra, length at maturity, spawning season, fecundity, sex-ratio

Date : 30-05-2015