Population structure of Indian scad fish (Decapterus russelli) that was landed at the Nusantara Fishing Port of Ternate, North Maluku, Indonesia

Abstract

Indian scad fish (Decapterus russelli) is a small pelagic fish species commonly caught in Indonesian seas. Excessive fishing efforts can cause population degradation, so it is necessary to understand its population structure. The purpose of this study was to analyze the population structure parameters of Indian scad fish, including growth parameters, cohort, and mortality. Sampling was done by Stratified Random Sampling method. Data analysis used the FISAT II application. Study results showed that there were 4 cohorts. The growth parameters of Indian scad fish obtained asymptote length (L∞) of 296.15 mm, coefficient of growth rate (K) of 0.60 per year, and initial age (t0) of -0.66 years. Value of coefficient of growth rate (K) indicated that growth of scad was relatively slow. The total mortality value (Z) was 0.51 per year, natural mortality (M) was 0.0034 per year, and fishing mortality (F) was 0.51 per year. So that the highest Indian scad fish mortality was caused by fishing mortality. The exploitation rate (E) was 1 per year, indicating that the Indian scad fish resources have been overexploited.