Short term culture of wild caught juvenile rabbit fishes (Siganus javus) in open sea cages at Palk Bay

Abstract

Objectives: The main objective of the study was to collect and rear the unmarketable, small sized S.javus which is mostly rejected by the traditional fisherman. During fishing activities, under sized S.javus ranging in sizes from 25 to 40 kg (< 30-40 % of total catch/day) is being captured. Due to very low marketable value these small fishes (<250 g) get rejected. Therefore, we utilized this as an economically viable option for utilization as seeds for rearing until they reach the necessary marketable size. Methods: Undersized juveniles (12-16 cm, 40 -55 g) were collected from nearby Olaikuda village,Rameshwaram using traditional traps made using bamboo and odai tree bark (Acacia planifrons). The collected juveniles were stocked in sea cages and fed with locally formulated plant based feed containing 28-32 % crude protein. Findings: Harvesting was successfully done after 140 days with 90 % survival. The average growth rate achieved was 2.5 g /day with FCR of 2.01. This resulted in an average harvest size of 400 g/fish from its initial stoking size of 50 g with an attracted market value of Rs. 150/kg. Novelty: Till date, no attempts were made to commercialize such harvesting techniques for the species Siganus javus in pilot scale in India (Except James, 1984). Keywords: Rabbit fish; Siganus javus; sea cage culture; rabbit fish culture; Siganidae