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Makassar Strait is a waters area with a large and relatively fertile water resource potential. The Makassar Strait area represents the confluence zone between the Pacific Ocean and Indian Ocean fish populations. The fertility of the waters makes this area one of the breeding zones for most aquatic biota. This study aims to map the catch of small pelagic fishes with water conditions in the Makassar Strait. The data used in this study was fish catches data from Makassar Strait waters from June to September 2021. Data on environmental conditions in the form of Sea Surface Temperature and chlorophyll-a concentration in the waters during the study period were obtained from the AQUA satellite with MODIS sensors, then combined with the Geographic Information System (GIS). The results of this study indicate that the sea surface temperature range in Makassar Strait waters was between 26.7°C–31.3°C and the concentration of chlorophyll-a was between 0.7 mg/m³ - 1.30 mg/m³. The highest catch points were at two points with the same catch of the purse seine, namely 4,000 kg at 118°51'E and 5°10'59"S and at 118°52'59"E and 5°3'S, while the lowest catch was 5 kg at 118°19'E and 4°57'S. It can be concluded that the presence of fish may be influenced by the water’s conditions favored by the target fish in the Makassar Strait. Abstrak Selat Makassar merupakan kawasan perairan yang memiliki potensi sumberdaya perairan yang cukup besar dan relatif subur. Kawasan Selat Makassar merepresentasikan zona pertemuan antara populasi ikan Samudera Pasifik dan Samudera Hindia. Kesuburan perairannya menjadikan daerah ini sebagai salah satu zona berkembang biak bagi sebagian besar biota perairan. Penelitian ini bertujuan untuk memetakan hasil tangkapan ikan pelagis kecil dengan kondisi perairan di Selat Makassar. Data yang digunakan dalam penelitian ini merupakan data tangkapan ikan dari Perairan Selat Makassar pada bulan Juni-September 2021. Data kondisi lingkungan perairan berupa Suhu Permukaan Laut dan konsentrasi klorofil-a perairan pada periode penelitian diperoleh dari satelit AQUA dengan sensor MODIS, kemudian dikombinasikan dengan Sistem Informasi Geografis. Hasil penelitian ini menunjukkan bahwa kisaran suhu permukaan laut di Perairan Selat Makassar antara 26,7°C–31,3°C dan konsentrasi klorofil-a antara 0,7 mg/m³ - 1,30 mg/m³. Titik tangkapan tertinggi terdapat pada dua titik dengan hasil tangkapan pukat cincin yang sama yaitu 4000 kg pada 118°51’BT dan 5°10’59”LS serta pada titik 118°52’59”BT dan 5°3’LS, sedangkan tangkapan terendah sebanyak 5 kg pada titik 118°19’BT dan 4°57’LS. Disimpulkan bahwa keberadaan ikan kemungkinan dipengaruhi oleh kondisi perairan yang disukai ikan target tangkapan di Selat Makassar.

Makassar Strait has been identified as an area of interesting studies for marine science and operational fisheries. It provides the unique ocean structures such as topographic feature, the main path of the Indonesia Throughflow (ITF) and dynamics of thermal fronts. The aims of this study were to map the dynamic spatial and temporal of the thermal fronts, and to describe their implications to the pelagic fisheries. We used satellite data of sea surface temperature (SST) for the period of January-December 2018 with spatial and temporal resolutions of 4 km and monthly, respectively. For fishery data, we used sampling data of skipjack tuna fishing ground distributions in October and December 2018. Thermal fronts throughout the year were estimated using a Single Image Edge Detection (SIED) algorithm and the available fishing ground data were overlain on the SST front map. The results showed that the spatial distributions of thermal fronts along Makassar Strait tended to be different every month. However, the thermal fronts were consistently detected near the upwelling area from June to September. Skipjack tuna fishing grounds associated with fish aggregating devices (FADs) developed in the northern area of upwelling in October. Two month later, the FADs and free swimming skipjack fishing grounds again well formed around the same location. It implies that the formation of the thermal fronts after upwelling contributes the positive effect on development of pelagic fishery especially skipjack in Makassar Strait.

The aims of this study were to compare skipjack catch between FAD and free school fishing grounds and to describe the effect of the oceanographic factors on either skipjack tuna Fish Aggregating Device (FAD) or free school. We used a field survey method for collecting the skipjack catch and the fishing positions for both near FAD and free school areas. Remotely sensed satellite data of sea surface temperature (SST) and chlorophyll-a concentration (Chl-a) were also used to extract the oceanographic data corresponding with both the fishing locations. To find out the vital oceanographic factors, we examined the characteristics of the oceanographic variables and skipjack catch using t-test. Results indicated that the fishing operations of skipjack tuna at FAD tended to locate areas of relatively higher Chl-a than at free school locations. We also found that skipjack tuna catch was higher near the FAD than the other area, where the Chl-a was the most significant factor that affected the difference. This study suggests that the number of skipjack tuna FAD in the coastal waters of Bone Bay should be calculated accurately to ensure and support the tuna fishing management in that study area.

Putri ARS, Zainuddin M, Musbir, Mustapha MA, Hidayat R. 2021. Mapping potential fishing zones for skipjack tuna in the southern Makassar Strait, Indonesia, using Pelagic Habitat Index (PHI). Biodiversitas 22: 3037-3045. Southern Makassar Strait is one of the potential fishing grounds for skipjack tuna in the Indonesian waters. Oceanographic factors become the primary factors that limit the distribution and abundance of fish. The study aimed to identify the relationship between fish distribution with sea surface temperature (SST) and primary productivity (PP) and map out the potential fishing grounds of skipjack tuna in the southern Makassar Strait. It used pelagic habitat index (PHI) analysis, which is strengthened by the results of correlation analysis in the form of generalized additive models (GAM) and Empirical cumulative distribution function (ECDF) analysis. The results showed that the distribution of skipjack tuna was significantly associated with the preferred range of SST 29-30.5°C and PP 350-400 mg C/m2/day. The potential fishing zone is well established near the coast to offshore of Barru and Polman waters (3°-6°S and 117°-119°E), with the peak season in May and October. The spatial pattern of potential fishing grounds for skipjack fishing is associated with hotspots (oceanographic preference), leading to increased feeding opportunities. This study suggests that the spatial pattern of high potential fishing zones could improve fishing, management, and conservation strategies along the southern Makassar Strait.

Penelitian ini bertujuan untuk mengidentifikasi potensi sumberdaya ikan pelagis besar dan memberikan gambaran kondisi oseanografi di WPP 713 secara temporal dan spasial. Data yang digunakan dalam penelitian ini adalah data statistik produksi perikanan tangkap serta data citra satelit berupa data suhu permukaan laut dan klorofil-a tahun 2005-2014. Data-data tersebut dianalisis menggunakan Sistem Informasi Geografis (SIG). Hasil penelitian menunjukkan produksi ikan pelagis besar tertinggi di WPP 713 pada tahun 2014 yaitu sebanyak 172.428 ton dengan Suhu Permukaan Laut (SPL) yaitu sebesar 29.4°C dan kandungan klorofil-a sebesar 0,34 mg m-³. Hasil penelitian ini dapat dijadikan acuan dalam manajemen operasi penangkapan ikan pelagis besar di WPP 713 sehingga operasi penangkapan dapat menjadi lebih efesien dan efektif dengan tetap memperhatikan keberlanjutan sumberdaya ikan.Kata Kunci: ikan pelagis besar, klorofil-a, suhu permukaan laut, satelit penginderaan jauh, WPP 713

Penelitian ini bertujuan untuk menghasilkan informasi zona potensial penangkapan ikan serta mengestimasi kelimpahan ikan Cakalang di perairan Selat Makassar berbasis data satelit dan teknik Sistem Informasi Geografis (SIG). Data yang digunakan terdiri dari data primer (titik koordinat penangkapan, suhu permukaan laut, klorofil-a, salinitas, dan jumlah hasil tangkapan) dan data sekunder (citra suhu permukaan laut, klorofil-a, kedalaman, kecepatan arus, dan salinitas). Prediksi kelimpahan ikan cakalang dihitung dengan persamaan multiple regresi kemudian dipetakan dengan teknik sistem informasi georafis. Hasil menunjukkan bahwa zona potensial penangkapan ikan cakalang di perairan selat Makassar pada bulan April – Juli 2018 secara umum berada pada perairan yang lebih dalam. Adapun prediksi kelimpahan ikan cakalang berdasarkan zona potensial penangkapan ikan pada bulan April diperoleh sebanyak 39,6430 ekor/km², pada bulan Mei sebanyak 24,0087 ekor/km², pada bulan Juni sebanyak 18,4314 ekor/km², dan pada bulan Juli sebanyak 8,5404 ekor/km². Kata Kunci: Ikan cakalang, Selat Makassar, kelimpahan, tangkapan

Flores Sea is one of the most productive fishing grounds within the Indonesian Fisheries Management Area 713 which has the unique physical structures such as topographic feature, the seasonal wind driven upwelling, and also the dynamics of frontal patterns. The purposes of this study were to map the dynamic spatial of the thermal fronts in the east and the second transition seasons, and to describe their implications to the skipjack fishery. We applied the satellite data of sea surface temperature (SST) for the period of June-October 2018 with spatial and temporal resolutions of 0.04 degree latitude and longitude and monthly, respectively. For fishery data, we used sampling data of skipjack tuna fishing ground distributions during this period. The thermal fronts were estimated using a Single Image Edge Detection (SIED) algorithm and the available fishing ground data were superimposed on the SST frontal maps. The results showed that the spatial distribution patterns of thermal fronts along Flores Sea tended to be different every month. However, the thermal fronts were consistently detected throughout the study period. Skipjack tuna fishing grounds started to develop in the eastern area of Selayar Island in June (before upwelling event) and reached a peak in October (after upwelling). During these months, the skipjack fishing grounds well formed around the thermal fronts with the distance of 0-40 km. It implies that the formation of the thermal fronts especially after upwelling gives a significant contribution on the development of skipjack fishery in the Flores Sea.

Spatial and temporal studies on the distribution of small pelagic fish by applying oceanographic parameters are essential for fisheries management. An understanding of the spatial characteristics of small pelagic fish distributions is important to optimize the sustainability of marine resource utilization. This study examined the characteristics of small pelagic fish fishing grounds through the analysis of oceanographic parameters using remote sensing satellite data and generalized additive model. Remote sensing satellite data (SST and chlorophyll-α) covering the area of Makassar Strait were obtained from NASA databases, with a spatial resolution of 4 km and monthly temporal resolution. Data on the geographical location and catch volume of small pelagic fish were obtained from a fisheries survey in the Makassar Strait. Remote sensing satellite data and fisheries survey data were plotted graphically to determine the environmental conditions at the sites where the small pelagic fish were caught. Catch volume and catch positions were mapped to show fish distribution. The results show that the highest point was around Barru waters with a catch of 30.70kg - 36.75kg. Small pelagic fish were caught in the SST range between 29.82° C - 31.32°C and mostly caught in chlorophyll-a between 0.34 mg/m3 - 0.62 mg/m3.

Skipjack tuna (Katsuwonus pelamis) plays an important role by pole and line fishery in the Bone Gulf, Indonesia, since it has a high economic value and wide market acceptance. The purpose of this paper was to assess the seasonal changes of skipjack tuna potential fishing ground in the Bone Gulf. We used pole and line fishery and oceanographic data of sea surface temperature (SST) and chlorophyll-a derived from satellite to figure out the seasonal formation of the potential fishing areas. We developed the spatial model to determine the potential fishing ground based on different levels of oceanographic preferences. The results showed that potential fishing grounds were mostly formed in the first transition season (particularly in May) as well as the west season (especially in November), which have a good association with the specific SST and chlorophyll-a of near 30 Deg C and 0.2 mg m-3, respectively. Most of the potential skipjack fishing ground formation developed along with the specific oceanographic signatures. It was likely that the potential seasonal changes of fishing grounds corresponded with enhanced feeding opportunity distribution pattern for skipjack schools. This suggested that these potential areas play an important for conservation and skipjack fishing management within the study area.

Komoditas unggulan sektor perikanan laut merupakan salah satu komoditas strategis untuk meningkatkan pendapatan asli daerah. Penelitian ini bertujuan untuk menentukan komoditas perikanan tangkap yang menjadi unggulan di Kabupaten Polman, Sulawesi Barat. Penelitian ini menggunakan metode deskriptif dan metode pengambilan sampel adalah purposive sampling berbasis data statistik tahun 2016. Analisis yang digunakan dalam peneltian adalah Location Quotient (LQ), dan analisis Specialization Index (SI). Penentuan komoditas unggulan apabila baik nilai LQ maupun SI >1. Perangkingan komoditas menggunakan indeks komoditi. Hasil penelitian menunjukkan bahwa komoditas perikanan tangkap Kabupaten Polman di Sulawesi Barat yang menjadi unggulan utama adalah ikan teri (Stolephorus Sp), ikan madidihang (Thunnus albacores), ikan cakalang (Katsuwonus pelamis) dan ikan biji nangka (Upeneus moluccensis). Diantara keempat komoditas unggulan tersebut, ikan madidihang memiliki nilai LQ dan SI yang paling tinggi yaitu 1.87 dan 10.19. Hasil ini berimplikasi pada pentingnya strategi penangkapan dan pengelolaan ikan tuna madidihang di Kabupaten Polman untuk meningkatkan pendapatan daerah. Kata kunci: Komoditas Unggulan, perikanan laut, LQ, SI dan Kabupaten Polewali Mandar

Mentri Supeno Park is an open public space in the form of a park located in the middle of the city in which its position is a strategic location as a social space. This park has various facilities, one of them is the Wi-Fi Network. A combination of open space and Wi-Fi has become a necessity in almost all levels of society to form community activity points that spread to both individual and groups on each side of the park. The purpose of this study was to find out how the role of Wi-Fi in generating social space in open spaces in the park, so it could be known the types of created social spaces and management of spaces that were obtained. This study used a qualitative method with a behavioral mapping approach as its analysis technique. The results of this study showed five types of social space activities, with types of individual and collective activities. With the results obtained, it is expected to provide recommendations for the management of social space, so it does not lead to uncontrolled things. Moreover, it can help build the character of the community and align with the regional development agenda.

Sangiang Island had been established as a Nature Recreation Park (TWA) in Indonesia, that requires comprehensive data support for good management. The rise of marine tourism that increased in TWA Sangiang Island behoove to be a concern, especially in coral reef ecosystem. The study aimed to determined the condition of the coral cover and the biomass composition of coral reef fishes, then to identify parameters that affect coral health and the coral reefs health index in TWA Sangiang Island. The observation was carried out in area near to the estuary (Legon Waru), entry point for shipping (Tembuyung), and diving tourism (Legon Bajo). The highest of biomass of target fish was Legon Bajo (0.013 kg / ha) and the lowest was Tembuyung (0.002 kg / ha). Coral reefs health index values in each station varied from 1 (low) to 4 (high). Coral reefs health index in Legon Waru was strongly influenced by live coral cover, and also in Legon Bajo was influenced by live coral cover, rubble and biomass of target fishes, while in Tembuyung was much influenced by fleshy seaweed cover. The results indicated that the coral reef ecosystem on Sangiang Island wasn’t in good condition as a whole.

The Atmospheric dynamic condition during heavy rainfall on 18 June 2016 in Banjarnegara was examined using the Weather Research and Forecasting (WRF) model. This study calculated hourly atmospheric instability indices and three kind of atmospheric dynamic parameters such as vorticity, vertical velocity, and divergence. Vorticity described cyclonic movements for the cloud growth, vertical velocity described the speed of lift force, and divergence described the existence of air mass encounter in the atmosphere. The final (FNL) data and suitable schemes are applied for the nested domains (27 km, 9 km, 3 km) in model. The result ofinstabilityindices is the convection was occured 1 hour before heavy rain. The result of vorticity is -0.25 × 10−3/s; 0.9 m/s in vertical velocity; and -0.5 × 10−3/s in divergence. From the study, it was also found that the process of cloud development has been seen for 30 minutes to 1 hour before the heavy rain.

This study aimed to compare the differences between characteristics of skipjack tuna (Katsuwonus pelamis) fishing grounds in the Gulf of Bone and in the Makassar Strait. We used catch size and volume data from FAD areas in the Gulf of Bone and Makassar Strait, and satellite image data including sea surface temperature (SST) and chlorophyll-a (CHL-a). We used ECDF (Empirical Cumulative Distribution Function) analysis to determine the relationship between the oceanographic variables and skipjack CPUEs that occurred in the Gulf of Bone and the Makassar Strait. The resulting data for the two fishing areas were then compared using the Spatial Analyst in ArcGIS 10.2. The analysis showed that the average SST and CHL in the Gulf of Bone (30°C and 0.3 mg m−3) were higher than those in the Makassar Strait (29.5°C and 0.24 mg m−3). The size of skipjack tuna caught in the two fishing areas was different. The mean total length of Skipjack tuna caught in the Makassar Strait was 23 cm, while in the Gulf of Bone it was 41 cm. There was little overlap in the size distributions. These data suggest that skipjack tuna caught around FADs in the Gulf of Bone tend to be larger than those in the Makassar Strait which may be stimulated by relatively higher productivity and thus feeding opportunity.

Fish Aggregating Devices (FADs) have become the preferred choice in skipjack tuna fisheries rather than looking for free-swimming schools (FSS) which is considered less effective. This study aimed to identify the effect of oceanographic conditions on skipjack tuna catches in the FADs versus free-swimming schools in the Makassar Strait. We collected fishing data from vessels using purse seine fishing gear and satellite-based oceanographic data (Sea Surface Temperature (SST) and chlorophyll-a (chl-a)) from May to July 2017. The satellite and catch data were analysed using a Generalized Additive Model implemented in R and mapped using Spatial Analyst in ArcGIS 10.6. The results showed that SST ranges in the FAD areas were relatively wider (29 – 31°C) than those in free-swimming school areas (29.5 – 30.5°C). The chl-a concentrations in free-swimming school areas were relatively higher (0.25 – 0.80 mg m-3) than those in the FAD areas (0.15 – 0.50 mg m-3). It was also found that mean skipjack tuna catches in the FAD areas (337 fish/setting) were relatively higher than in the free-swimming school areas (145 fish/setting). These findings suggest that the high skipjack tuna catches in Makassar Strait were significantly affected by specific SST ranges and relatively low chl-a.

Skipjack tuna is an important fishery species, targeted by purse seine and handline fisheries in Makassar Strait. Fish distribution patterns are markedly influenced by several underlying oceanographic factors. This study aimed to assess the relationship between skipjack CPUE and some oceanographic variables, and map out the distribution pattern of this fish in the study area during January-May 2018. To meet these objectives, we combined satellite data of sea surface temperature (SST) and chlorophyll-a concentration (chl-a) with catch data. We used generalized additive models (GAMs) to explore skipjack abundance in relation to the oceanographic conditions and we employed the gravity centre of fishing ground movements to map the fish distribution pattern. Results indicate that SST and chl-a significantly influenced skipjack tuna CPUE. The fish schools were mostly located in the eastern Makassar Strait. In January skipjack schools were initially in Majene offshore waters and moved to Mamuju waters in February. The skipjack schools returned to the border area between Polman and Majene waters in March and then made a continuous migratory journey to the south-western areas of Barru and Pare-pare offshore waters in April. In May, the skipjack tuna returned to concentrate in southern areas of Majene waters. We proposed that the fish schools followed a clock-wise distribution movement pattern where the habitat displacements may have a link with the dynamic ranges of preferred oceanographic conditions (habitat hotspots). It is likely that these areas provide good feeding opportunities for skipjack tuna.