Biology reproduction and population dynamics of Caesio cuning (Family: Caesionidae) in Kendari Waters, Banda Sea, Indonesia

Abstract

Abstract The Redbelly yellowtail fusilier with the local name Ekor Kuning (Caesio cuning) is a reef fish species found in the waters of the Indo-West Pacific. In Indonesia, it is an economically important fish and is dominantly caught by gill nets, traps and handlines. The intensity of fishing that is carried out continuously is feared to threaten the stock of the species in nature. In order to make its use sustainable, this study attempts to evaluate population dynamics and reproductive biology. The study was carried out in the Kendari waters of the Banda Sea, Indonesia, between April and December 2018. The findings indicated that this fish’s length distribution covered a range of 11,6-29,0 cm FL and the growth pattern was isometric with the length-weight relationship equation W=0,0206L3,0612. The spawning season peaked in November, and the sex ratio did not deviate considerably from 1:1. The length at first maturity (Lm = 21,73 cm FL) was longer than the length at first capture (Lc =15,5 cm FL) The VBGE for yellowtail was Lt = 30,45 [1 – e−0,89(t+0,171)]. The value of mortality due to capture (F = 2,19 per year) is greater than natural mortality (M = 0,44 per year). The exploitation rate (E) was recorded as 0,72 per year and the SPR value is 0,22 per year. Based on these parameters, it indicates that the level of exploitation of Caesio cuning in Kendari waters is in overfished so that management needs to be implemented by limiting the smallest fish size that can be caught and to reduce fishing operations during the spawning season.