Biological aspect of mackerel scad (Decapterus macarellus Cuvier, 1833) in Prigi waters Trenggalek Regency East Java Indonesia

Abstract

Abstract Mackerel scad (Decapterus macarellus) is one of the dominant catches in the Java Sea. Sustainability of Makarel scad resources (D. macarellus) needs to be maintained and managed optimally and sustainably. This research was conducted in Prigi Waters, Trenggalek East Java. starting December 2018 to September 2019 which aims to identify biological aspect and food composition of Mackerel scad (D. macarellus). The method used in this study is descriptive and uses a random sampling method. 1610 fish samples. Acquisition of Total length (TL) mackerel scad (D.macarellus) ranges from 16.8-35 cm and weighs between 42-328 grams. The Growth Pattern on (D. macarellus) is negative Alometric with the equation W =0.0163L 2.8447. The ratio of male and female is 1: 1 The Gonad somatic index\value is 1.41%. The value of Lm Female is 25,70 cm Lm male 25,92 cm and the value of Lc is 26,68 cm. L∞ Growth Parameter = 38.73, K = 0.77, to = -0.194 years. The composition of mackerel scad in total sampling seen from the index of preponderance consisted of Zooplankton 51% (arthropods, molluscs, cnidaria, annelida, chordata) and 49% phytoplankton (ochrophyta, bacillarophyta, chlorophyta, cyanobacteria, protozoa, ciliopora, cyanophyta)