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.

The sandfish Holothuria scabra is a sea cucumber with a very high economic value. Sandfish cultivated in brackish water ponds will face a high salinity problem in the dry season. This study aimed to analyse the effect of high salinity on sandfish mortality. The study was done in a controlled tank in which the sea water was allowed to evaporate naturally, without the addition fresh water, so that the salinity increased continually. High salinity can cause injury and death to sandfish; before death, there was an evisceration. The death salinity of sandfish was 47 ppt. Sandfish have a greater range of tolerance to salinity than other sea cucumber species.

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”.

The sandfish Holothuria scabra is a benthic animal of high ecological and economic value. The high economic value of sandfish has led to declining populations due to overfishing. Initiatives to improve sandfish production have included restocking, sea-ranching and aquaculture (captive breeding and grow-out). These initiatives require a supply of animals (seed and/or broodstock) that often originate far from the location where they are needed. This calls for a good transportation system so that the sandfish arrive in good condition. This study aimed to assess the evisceration rate of sandfish transported using open and closed transportation modes. During the study, different modes of packing, density, transportation time, and holding time were evaluated. This study indicated that delivery using open systems gave poor results; besides being less practical, post-transport evisceration was very high. The ratio of oxygen and water and the packing density did not appear to affect the sandfish evisceration rate. Evisceration seemed to be triggered by the presence of dead and decaying sandfish in the bag. Sandfish that survived transportation generally recovered swiftly after being placed in a pre-prepared holding tank. The transported sandfish were used for multitrophic aquaculture and the post-transport survival ratio was very high.