Population Structure of Vermiculated Spinefoot (Siganus vermiculatus Valenciennes, 1835) in the Waters of Makassar Strait, Indonesia

Abstract

Intensive exploitation of vermiculated spinefoot in the Makassar Strait suggests a potential shift in population dynamics. This study aims to examine various biological aspects of the species, such as size distribution, growth patterns, condition factors, sex ratio, gonad maturity, and the size at first gonad maturity. Conducted through a survey method in the waters of the Makassar Strait, the research utilized tickle net fishing gear continuously operated in the area. Findings revealed that male fish had an average length distribution of 18.3 ± 0.325 cm, while female fish measured 19.8 ± 0.496 cm. Both genders exhibited negative allometric growth patterns. The condition factor was 0.999 ± 0.004 for males and 1.001 ± 0.005 for females. The sex ratio appeared unbalanced, with gonad maturity stages ranging from immature to spawning. The size at which males first matured gonads was 21.587 cm, while for females, it was 19.229 cm, indicating faster gonad maturation in females. To ensure sustainability, fishing efforts should target individuals above the size at which gonads first mature.