Population Dynamics of Mackerel Scad (Decapterus macarellus) in the Banda Sea

Abstract

Mackerel scad is a one of small pelagic fish that has important economic value in the waters around Ambon Island. This study aims to determine population dynamics including the length distribution, growth, gonad maturity, mortality and the rate of exploitation of mackerel scad in the waters around Ambon Island. This research was conducted during the period of September 2016 to July 2017. Total fish samples analyzed were 2534 individuals. The total length (TL) of fish caught during the eleven months of the research ranged from 9.0 - 31.9 cm with an average length of fish caught of 20.11 cm. Growth curve formed with the equation: Lt = 33.35 [1-exp0.560 (t + 0.2799]. Gonad I maturity level was 8.13-10 16%, TKG II (gonad II maturity level) was 46.49-49.11% , TKG III (gonad III maturity level) was 16.54-18.93%, TKG IV (gonad IV maturity level) 24.34-26.02%, and TKG V (gonad V maturity level) was 0.07-0.21%, F value was 1.36/year with the rate of exploitation (E) of 0.53/year, the total mortality rate (Z) = 2.58/year and the natural mortality rate (M) = 1.23/year.