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The variability of atmosphere-ocean interactions highly influences the distribution of fishing zones in the surrounding Indonesia Through Flow (ITF) channel, such as the WPP-716 region. Therefore, the seasonal determination of the fishing zone is crucial in this zone as one of the regional fisheries managements in Indonesia. This study aims to create a potential fishing zone (PFZ) model in the Regional Fisheries Management of Indonesia (WPP-RI) 716 based on the remote sensing satellite data. This study used the daily SST data extracted from the Suomi-National Polar-Orbiting Partnership-Visible Infrared Imaging Radiometer Suite (SNPP-VIIRS) image Level 2 from 2018 to 2019. A Single Image Edge Detection (SIED) method is applied to determine the PFZ points. Supporting data, such as sea current patterns, chlorophyll-a, fish-catching zones and Catch per Unit of Effort (CpUE), are also considered to bolster this study's findings. The models were validated and compared with the results established by central authority fish catch data. Of particular concern, the highest detection of PFZ is observed during the second transitional season, reaching 1835 points scattered all over the study area. The frequently detected PFZ is identified in northern Sulawesi and Sangihe Islands, where the circular eddy current observed during the second transitional season, ranging from 0.6 to 0.8 m/s, indicating upwelling (high productivity) events proven by the variability of surface temperature and chlorophyll-a and aligned with the high value of CpUE (ranging from 20 to 28 kg/GT/day). The developed model is expected to be a basis for further decision-making regarding fishery resources management in the study area. [ABSTRACT FROM AUTHOR]

Ketersediaan informasi tentang informasi Potensi Penangkapan Ikan (PPI) sangat diperlukan untuk meningkatkan produktivitas perikanan. Secara tradisional, nelayan memanfaatkan indera dan kebiasaan turun-temurun mereka untuk menentukan PPI. Secara tradisional, nelayan memanfaatkan panca indra dan kebiasaan yang bersifat turun-temurun untuk menentukan PPI. Cara ini, selain kurang efisien, juga bisa menyebabkan ekploitasi berlebihan jika kegiatan penangkapan ikan dilakukan pada tempat yang sama secara terus-menerus. Keberadaan teknologi penginderaan jauh dapat dimanfaatkan untuk penentuan PPI secara lebih cepat dengan tetap memperhatikan aspek akurasi dan sebaran spasial. Salah satu metode penentuan PPI berbasis data penginderaan jauh, memetakan daerah thermal front terlebih dahulu sebelum menentukan PPI melalui interpretasi manual berdasarkan keberadaan piksel diantara suhu perairan yang hangat dan dingin. Interpretasi manual memiliki keterbatasan, diantaranya: tergantung pada manusia dan memerlukan waktu yang lama. Untuk mengatasi keterbatasan tersebut, dalam penelitian ini, metode Single Image Edge Detection (SIED) yang dikembangkan oleh Cayulla dan Cornillon diaplikasikan dalam bentuk toolbox agar bisa digunakan secara otomatis. Data Suhu Permukaan Laut (SPL) yang diperoleh dari MODIS Level 2 (6 April 2018) selanjutnya diproses dengan menggunakan toolbox ini dan berhasil mendeteksi 22 titik PPI di perairan selatan Pulau Jawa. Sementara itu, deteksi PPI dengan metode Temperature Gradient Analysis (TGA) yang dilakukan secara manual menghasilkan 28 titik. Terdapat 20 lokasi titik yang sama menggunakan dua metode ini. Penggunaan metode SIED berbasis toolbox dapat mempercepat pemrosesan data, mengurangi kesalahan manusia dengan tingkat akurasi 64%.

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.