Korespondensi - Length-weight relationship, body condition, and fishing gear selectivity of shortfin scad (Decapterus macrosoma) landed in Banjarmasin fishing port, Indonesia

Abstract

The present study provides scientific information on growth pattern and relative condition of the Shorfin scad (Decapterus macrosoma) landed in Banjarmasin fishing port, Indonesia. A total of 313 individual scads comprising 178 males and 135 females, ranged from 152-225 mm total length and 37-110 g weight were investigated. The body shape of both male and female showed isometric growth pattern (b = 3.02-2.96). The regression coefficient was significantly different between the sexes. The total length, body weight, body depth, W/TL and BDD/TL ratios, and also condition factors of female were comparatively higher than those of male (P < 0.001). The highest percentage of catch falls between 180 and 189 mm TL (32.59-40.45%) and weighted between 50 and 59 g (20.65-21.79%). The relative condition factor values were ranged of 0.799-1.433 reflecting well-being of fish samples. The estimated length at first capture (Lc50) and selection factor values were 180 mm and 3.54 for male, and 185 mm and 3.64 for female. In the present work, the purse seine is considered male-biased gear, with the sex ratio of 1.3: 1. Outcomes of research could be useful for a sustainable pelagic fisheries management and the precautionary measures of over exploitation for this species