Some Aspects of the Reproductive of Japanese Threadfin Bream (Nemipterus japonicus Bloch, 1791) Caught in the Area Around the Artificial Reef In the Pitu Sunggu Waters of the Makassar Strait

Japanese Threadfin Bream is a demersal fish commonly found around artificial reefs. Food availability in the artificial reef ecosystem is essential for the sustainability of this species. Hence, this research aimed to determine several aspects of bio-reproduction of Japanese Threadfin Bream caught in the artificial reef (bioreeftek). Samples were taken using handline fishing, twice a month (April-July 2020) in Pitu Sunggu Waters, Makassar Strait. The samples were observed for its reproduction aspects. The result showed that the Japanese Threadfin Bream fish caught have a balanced sex ratio between males and females, 1:1.03. The analysis of the gonad maturity stage obtained was II-IV, and the gonado somatic index ranged from 0.541-0.940 for males and 1.156-2.358 for females. The first mature Japanese Threadfin Bream size was 18.29 cm for males and 16.99 cm for females. The Japanese Threadfin Bream fish fecundity ranged between 35.042-42.061 eggs.