Long-Term Monitoring of Parrotfish Species Composition in the Catch of Fishermen from the Spermonde Islands, South Sulawesi, Indonesia

Abstract

Abstract Parrotfishes, aside from playing an important ecological role in coral reef ecosystems, are an economically important fish group exploited for human consumption. Excessive exploitation of parrotfishes could cause ecological disturbances in the coral reef ecosystem. This study aimed to examine the species composition and population dynamics of parrotfishes caught by fishermen in the Spermonde Islands, South Sulawesi, Indonesia. Parrotfishes were collected from the catches landed in Makassar Fisheries Port. Monthly samples comprised all parrotfishes landed on the sampling day. Sampling was carried out throughout 2014 and from January 2018 to May 2019. The parameters observed were the name and the number of each species. The composition and dynamics of the Parrotfishes species were analysed using the Diversity Index, Evenness Index, Dominancy Index, and Similarity Index. During the study, 6,684 parrotfishes were collected belonging to 34 species, of which 10 species had a mean sampling presence over 90%, i.e. Chlorurus bleekeri, C. capistratoides, C. sordidus, Scarus chameleon, S. flavipectoralis, S. ghobban, S. niger, S. quoyi, S. rivulatus, and S. schlegeli. Long-term monitoring of parrotfish species composition indicate that parrotfish diversity was consistently at the moderate level, indicating moderate productivity, fairly balanced ecosystem conditions, and moderate ecological pressure. Over the study period, parrotfish species were evenly distributed, no one species was really dominant, and the high Similarity Index indicated little change in species composition. These results indicate that the fishing pressure from traditional capture of parrotfishes using nets and spears has not had a serious impact on the condition of parrotfish resources.