남해 연안의 보리새우(Marsupenaeus japonicus) 개체군의 생식 생물학적 연구

Abstract

Population dynamics of Marsupenaeus japonicus were investigated in the south-eastern coastal area of Korea, between May 2000 and October 2000. This paper describes sex ratio, length composition, sexual maturity population and reproductive aspects about Marsupenaeus japonicus. The sex ratio showed that male is more numerous than female. Female maturity was determined by frequency both of ovigerous females and of females with maturing ovary. The size at 50% sexual maturity was estimated as carapace length 49.62mm. The gonadosomatic indices (GSI) showed the highest value during four mounths from June to September. Based on the month when there was high proportion of incubating females with a high GSI, the estimated spawning season of Marsupenaeus japonicus. was September. Spawning by a single female seems to occur consecutively in a single reproductive period. These spawning seasons was controlled the water temperature, so deeply relationships between gonadosomatic indices and water temperature.