Population Parameters of Shortfin scad Decapterus macrosoma (Bleeker, 1851) in Antique, Philippines

Abstract

Growth, mortality, exploitation rate, and recruitment of Decapterus macrosoma in the waters off Antique province, Philippines, were investigated based on the length-frequency data collected from April 2019 until March 2020. Using the FISAT-II software, D. macrosoma growth parameters were computed as follows: L∞ = 26.18 cm TL, K = 1.00 yr-1, ø' = 2.836 yr-1, and an estimated life span of 3 years. Mortality values were estimated as: total mortality (Z) = 4.66 yr-1; natural mortality (M) = 1.88 yr-1; and fishing mortality (F) = 2.78 yr-1. The exploitation rate (E) was computed as 0.60 while Emax was 0.42 yr-1. The length at first capture Lc/L50 was estimated at 11.96 cm TL. There were two recruitment events in one year: July and December. D. macrosoma in Antique was growing isometrically and in good condition with the relative condition factor (Kn) values ranging from 0.99 to 3.39. The computed exploitation rate suggested that D. macrosoma faces a high level of exploitation in Antique waters. These results offer valuable information on the utilization, conservation, and management of D. macrosoma in the East Sulu Sea area.