Spatial distributions of the thermal front and of catches of mackerel (Scomberomorus commerson) in the Java Sea, Indonesia

The thermal front can be used as an indicator to estimate the potential fishing ground in the ocean, especially for pelagic fishes. To determine the potential fishing areas, it is necessary to analyze the relationship between the distributions of the thermal front and mackerel catches. This research was conducted in the Java Sea, at the central part of the Indonesian seas by using oceanographic satellite datasets. The research method used was descriptive analysis with spatial and temporal approaches. Data on average sea surface temperatures and mackerel catches were analyzed from 2018-2020 (on a monthly basis). Based on the results, the thermal front distribution from 2018 to 2020 is mostly located near the coast, where the frequency of occurrence fluctuates every month and season. Data on mackerel catches are spread throughout the Java Sea, with an average sea surface temperature of 29°C. In general, it can be concluded that the mackerel catches distribution does not always coincide with the occurrence of a thermal front, except for January and August 2020. We highlighted that there is no direct relationship between the fishing location and the thermal front.