Wrasses are reef fish that play an important role in maintaining the health of coral reef ecosystems. Some species of wrasse, such as the Napoleon wrasse Cheilinus undulates, have high economic value and are threatened with overexploitation. This study aims to analyse the species diversity of wrasses caught by fishermen operating in the Spermonde Islands, South Sulawesi, Indonesia. The study was conducted from January 2018 to May 2019, on a monthly basis. Sampling was carried out by collecting all wrasses landed on one chosen day at Makassar Fisheries Port. The species diversity parameters observed were the species name and the number of individuals of each species. Based on these data, the diversity index, evenness index, domination index, and similarity index were calculated. Wrasse diversity was always in the medium range, indicating that ecologically wrasse habitat is still quite productive and has remained balanced over a considerable period time. It appeared that capture fisheries had not caused serious problems for the wrasse community diversity and structure.
The redbreasted wrasse Cheilinus fasciatus is an ornamental fish exploited for the marine aquarium trade. Even though it has white flesh, the redbreasted wrasse is not popular as a food fish because the flesh is quite thin. The redbreasted wrasse is widely distributed in the Indian and Pacific Oceans. It lives in tropical waters at depths of 4 to 60 m and at temperatures of 23 to 27°C. The objective of this study was to describe the gonad maturity stages of this fish using macroscopic characteristics. Sampling was carried out at Makassar Fishing Port from January 2018 to May 2019. The parameters observed in both male and female specimens were gonad length, width, weight, and gonad colour. Each specimen was also weighed and measured. Five gonad maturity stages were identified and described: Stage I (Immature or transition), Stage II (Early maturation), Stage III (maturation), stage IV (mature) and Stage V (post spawning or spent). These stages were described based on macroscopic structure and morphometric parameters of the gonads. The five stages coincided with changes in the Gonadosomatic Index (GSI), indicating that the five stages were valid. These stages could be used as a practical reference for identifying gonad maturity and describing the reproductive cycle of the redbreasted wrasse C. fasciatus.
As the largest trepang producer in the world, Indonesian trepang product still depends on wild catches. This wild catch could cause overfishing. In many fishing areas, sea cucumber populations have decreased to the point where they can be considered as a rare species. The wild catch could lead to a negative impact on size at maturity. Biologically, there are two types of reproductive strategies at marine organisms, i.e. ‘r-selection’ and ‘K-selection’. The ‘r-selection’ type was found in organisms that are dominantly controlled by their environmental factors and tend to reach physical maturation faster, while the ‘K-selection’ type was controlled more by biological factors, such as the presence of competitors. This study aims to analyze the size at the maturity of sea cucumber Holothuria scabra for different years to find out if the size at maturity can be used as a reference of the overfishing sign in the Wallacea region. The H. scabra or sandfishes were taken from the catches of fishermen at the Sub-district Liukang Tupabbiring Utara, Pangkep Regency, South Sulawesi, Indonesia. The Liukang Tupabbiring area is in the Spermonde Islands region, which is part of the Wallace line trajectory. Samplings were carried out for four years, from 2016 to 2019. The parameters measured were a total length (TL), total weight (TW), and gutted body weight (BW). The parameters observed were the color and stage of the gonad. The sizes at maturities were defined as the percentage of sexually mature, which were the sandfish with gonad stages of III, IV, and V. The study reveals that the size at maturity of sandfish was reached at a smaller size than previously reported. Biologically, smaller sizes at maturity could be a sign that sandfish has overfishing. As one organism whose biological organ structure was still primitive, Sea cucumber probably maintains the continuity of its generation by adapting reproductive strategy “r-selection type”.
Parrotfishes have an important ecological role in the coral reef ecosystem of the Spermonde Islands. The Spermonde Islands is located in the Makassar Strait, who was Wallace’s line trajectory. The Spermonde Islands consist of 120 islands, which have an area of around 2,500 km2, consisting of 50 vegetated islands and 70 non-vegetated sand dunes. Vegetated islandswere inhabited around 50,000 people. The ecological role and economic value of Parrotfishes place Parrotfishes in a paradoxical situation. Economically, Parrotfishes are an important protein resource for coastal and highlands communities. The Socio-economic contribution of Parrotfish can be overlooked, especially after the call not to eat Parrotfishes. For this reason, it necessary to overview the species composition and abundance of the Parrotfishes catch in Spermonde Islands by a monthly sampling of Parrotfish landed at Makassar Fisheries Port. The study aims to analyze the species composition and abundance for two different sampling periods (20014 and 2018) and to analyze their annual similarities. The study was expected to provide a preliminary description of the Parrotfishes. The number of species found in 2014 was 31, and in 2018 was 34. The similarity index between 2014 and 2015 was 0.912. The similarities indexes for monthly catches were lower. It was between 0.423 (May) and 0.680 (December). The catch was randomly distributed; this result shows that there were no target species in the catch of Parrotfish; the fishermen caught whatever Parrotfish they found. The sample conditions prove that large-sized Parrotfish were captured using the spear, whereas the medium and small size of Parrotfish seems to be captured using the net. The net use was quite worrying because the net was generally not selective. In order to maintain a balance between Parrotfish’s ecological role and socio-economic functions, regulations should be made regarding the prohibition on parrotfish catch with nets. It is recommended that Parrotfish should only be caught using the spear regularly and orderly so as not to damage the coral reefs.
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.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.