Reproduction of the Shotted halibut in the southern Korean waters

Abstract

was investigated based on the samplescaptured in South Korean waters from January 2008 to December 2009. Gonadosomatic index began toincrease in December , and reached maximum between January to March . After spawning it began todecrease from May . Reproductive season was estimated to January -April , with peak in February . Fecunditywas proportional to the size of the female , with the clutch size varying from 170,000 eggs in the smallestfemale (total length , 28.9 cm ) to 1,300,000 eggs in the largest (total length , 41.5 cm ). Size at 50% sexualmaturity (TL 50), determined from mature females , was 28.8 cm . Annual reproductive cycles of this speciescould be divided into six successive stages ; immature stage (May -October ), nucleolus stage (November -January ), yolk vesicle stage (January -February ), vitellogenic and ripe stage (January -April ) and spent stage(April -May ).Keywords: Maturation , Spawning , Annual reproductive cycle , Shotted halibut , Southern Korean waters