11 968 Sparus marcrocephalus with average body length of 60 .2mm were tagged and released in Daya Bay during 1997 .955 Sparus marcrocephalus were recaptured and the recapture rate was 8 .0 %.The most part of them distributed in the shallow waters along the coast of the top Bay , only few appeared in the ialands of the middle Bay .The tagged fish were well growing , the average body length of them had got to 235mm after 240 days .