Urgent need for sustainable fishing of Blue-barred Parrotfish Scarus ghobban (Forsskal, 1775) in Wallace Line, Spermonde Islands, Makassar Strait, Indonesia

Abstract

The Spermonde Islands has an area of approximately 2,500 km2 and 120 islands. These reefs are crossed by the Wallacea Line. The Spermonde waters are a fishing area located on the densely populated coast of South Sulawesi Island. Ecologically, Blue-barred parrotfish Scarus ghobban has an important role in controlling the macroalgae population which can inhibit coral growth. Economically, Blue-barred parrotfish has important economic value because besides being consumed, it is also an ornamental fish for sea water aquariums. The high economic value makes Blue-barred parrotfish exploited intensively. Until present there has been no research on the exploitation rate of Blue-barred parrotfish in the Spermonde Islands waters. This study aims to analyse the exploitation rate of Blue-barred parrotfish in the waters of the Spermonde Islands, South Sulawesi, Indonesia. Fish samples were obtained from the fishermen catch operating in the Spermonde Islands waters who landed at the Paotere Fish Landing in Makassar City in 2020. Age groups were analysed using the Bhattacharya method. The growth rate was estimated using the Von Bertalanffy method. Total mortality (Z) was estimated using the catch conversion curve method. The natural mortality rate (M) was estimated using the Pauly empirical formula. The catch mortality rate (F) was estimated using the equation F = Z-M. The exploitation rate (E) was estimated using the Beverton and Holt equations, namely E = F/Z. The growth rate equation was Lt = 75[1 - e−0.31(t-0.4166)]. The total mortality rate was 6.84, the natural mortality rate was 0.65, the fishing mortality rate was 6.19, and the exploitation rate was 0.90. The high exploitation rate indicates that the Blue-barred parrotfish in the Spermonde Islands requires an urgent call for sustainable fishing.