Reef Fish Resources in Various Condition of Seagrass Density in Pasi Island Waters, Kepulauan Selayar District, South Sulawesi Province

Abstract

Seagrasses are marine angiosperms, distributed in both tropical and temperate coastal waters creating one of the most productive aquatic ecosystems on earth. Due to the high primary production and a complex habitat structure, meadows formed by seagrasses support a variety of benthic, demersal and pelagic organisms. Many fish species are attracted to seagrass habitats for foraging and shelter, especially during their juvenile life stages. Thus, seagrass meadows are valuable resources for fisheries at both local and regional scales. The study presented the community structure, size distribution, species composition and spatial distribution of reef fish in seagrass habitats at Pasi Island waters. Sampling of fish was conducted in daylight and night using a small trawl. The total abundance and biomass of the reef fish in this research was 431 individual (13129 gram). Out of 55 different reef fish species from 24 families were recorded during the study, only one species accounted for more than 25% of the total abundance and biomass is Siganus canaliculatus. The study showed that the diversity and dominant indices of fish were generally significantly higher at station V with sand and reef fraction substrate dominated by Thalassodendron ciliatum and Cymodocea serrulata. Seagrass species with high density and percent cover value as Syringodium isoetifolium, Cymodocea serrulata and Thalassodendron ciliatum has a high fish diversity value. Seagrass species that has large and long leaves such as Thalassia hemprichii and Enhalus acoroides favored by reef fish planteater (herbivore) i.e. Siganus canaliculatus (Siganidae), Apogon melas (Apogonidae) and Scarus forsteni (Scaridae).