Population Dynamics of Kurisi Fish (Nemipterus hexodon) from Madura Strait

Quantitative estimation over the size of fish populations is needed in the development and management of fish resources. Utilization of fish resources can be performed optimally when the stocks and the distribution of fish resources is known that the exploitation policy can be done properly without endangering its sustainability. This study aimed to investigate the length-weight relationship of ornate threadfin bream (Nemipterus hexodon), the growth parameters (maximum length, age and growth rate), yield/recruit (Y/R) and biomass/recruit (B/R) of threadfin bream and the level of exploitation. The research was conducted in the Madura Strait in February-December of 2010. The biology and some aspects of population dynamics were studied. Length weight relationship W= 0.05 L2.47. Male and female sex ratio 1: 1.178. The mature fish gonad ratio of threadfin bream occurred in February and October. Lm= 16.42 cm and there were 7 months of the year Lc Lm. Growth equation parameters by von Bertanlanffy L∞= 30 cm, k= 0.4, to= -0,001. The exploitation rate (E) was 0.48 E0,5 (0.311). The results of this study suggest that the exploitation rate should be reduced to 35% to maintain adequate spawning biomass of the fish at Madura Strait.