Fine-scale fishery patterns reveal challenges and opportunities for coastal management and conservation in Madagascar

The blue economy agenda has generated tensions over marine space use, often marginalising small-scale fisheries in development policies. Boat tracking technology has only recently begun to be applied in these fisheries, but it offers a promising approach to accurately map fishing distribution. In this study, we explored how environmental, technological, and social factors influenced fishers’ spatial behaviour and catches at sea in one of the Madagascar's most heavily exploited coral reef fisheries. We recorded boat movements at 30 s intervals and reef fish catches simultaneously during a 12-month participatory survey. The spatial distribution of annual fishing effort (h·ha−1) and fish catch rates (kg·ha−1) was characterised by fishing community and gear type (beach seine, mosquito net trawl, gillnet, handline, and speargun) at 250−m resolution. A total of 75 reef fish families were recorded in catches (1,466 t·yr−1) across approximately 218 km2. Annual catch rates of the seven dominant families (comprising 62% of total catches) were highly variable and heterogeneous (mostly 1–391 kg·ha−1) across marine habitats. A total of 7,359 tracks by 521 boats were recorded. Fishing pressure was highly variable spatially (mostly 1−150 h·ha−1) among communities and gear types. The results revealed preferential target areas, informal marine tenure, limited travel distance to fishing grounds, and overexploitation patterns within the fishery, offering critical insights for fishery management and inclusive marine spatial planning. This study showed the usefulness and opportunities of deploying combined boat tracking and catch surveys in small-scale fisheries through participatory research.