1Corresponding author
The feeding biology, spawning season, size at first maturity, sex ratio and fecundity of the commercially important lizardfish (Saurida undosquamis) from Neendakara area, south west coast of India were studied. Fishes formed the predominant food item. Diversity of the prey items showed maximum value (H'log 2–3.61±0.11) during the post monsoon season and minimum during the monsoon season (2.89±0.17). The richness (1-lambda') also showed a similar of trend and varied from 0.81±0.13 (monsoon) to 0.91±0.01 (post monsoon). The size at first maturity (50% incidence of mature fish) was 195 mm. But when the size at first maturity was calculated by adjusting the proportion of maturity percentages, the maturity size was found to be 140 mm. This method is advantageous from the point of view of fisheries management as above 140 mm species can be exploited rather than above 195 mm. The gastro somatic index was found maximum during postmonsoon and minimum during the monsoon season showing an inverse relationship between feeding and spawning. This species was found to spawn from August to January with a peak in November. The fecundity values ranged from 19, 856 in a fish measuring from 20.1 cm in length (97 g) to 79,282 in a fish of 29 cm (290 g). The overall sex ratio (1:1.2) was found to deviate significantly from the expected 1:1 ratio. (χ2 = 19.1, p<0.005). High gonadosomatic index values were observed during October-December and that can be attributed to the spawning activity of the fish during the period.
Fecundity, Gastrosomatic Index, Maturity, Neendakara
