Reproductive biology of the white spotted rabbit fish, Siganus sutor, in culture conditions

Growth of gonads and spawning time in white spotted rabbit fish, Siganus sutor, in culture conditions were surveyed. Around 800 juveniles weighing 50-80g were captured from wild and stocked at a density of a15 ind/m ^(3) in concrete tanks during years 2004-2005 located in the Persian Gulf &Oman Sea Ecology Research Center. The fishes were cultured for about 12 and 24 mounts to obtain 1 year and 2 year old specimens. Culture was continued till the year 2007. Using 574 records, the length-weight relationship was determined as W=0.0155(FL). Results revealed that Siganus sutor has alometric growth. Monthly changes in GSI showed the lowest GSI values at stage I and V. We observed that GSI values of females and males peaked in April and May. The total fecundity of Siganus sutorranged from 170,000 to 1,300,000 oocytes in specimens of 22-35cm, F.L. 215-800 g B.W. and ovary weight of 15-117g. The average (cSE) total fecundity was 737931.03 ±77503.41 oocytes per female. The relative fecundity ranged from 458.47 oocytes to 2303.80 oocytes per g B.W. with an average (cSE) of 1606.31 ±131.89 oocytes per g B.W. Results showed the best time for S. sutoe to culture is month of May According to the results, one year old males are mature and produce sperm whereas females are ready to reproduce at age 2