Abstract
Area-based management in small-scale fisheries (SSF) is essential for ensuring the sustainability of marine resources, safeguarding ecosystems, and securing livelihoods. Effective management requires understanding the spatiotemporal variability of resource abundance and fishing effort in complex coral reef fisheries. This study supports the management of the Marine Protected Area (MPA) of the Bay of Ranobe (163 km²), southwestern Madagascar, by integrating fine-scale fisheries dynamics. An extensive participatory survey was conducted over 15 months (October 2021–January 2023) with 327 fishers to collect catch data, spatial data of fishing grounds, and effort data using GPS trackers. A spatiotemporal model built with the sdmTMB R package estimated Catch Per Unit Effort (CPUE in kg/min) as a proxy of abundance at a fine-scale 0.25 km² resolution. Results revealed high spatiotemporal variability (SD = 1.02), with resource distributions shifting across habitats and months. CPUE maps indicated higher values on the reef outer slope, decreasing toward inner bay habitats. By combining fine scale CPUE predictions with fisher movement data, the study provided key insights for adaptive fisheries management. The first application of this model in an SSF context demonstrates its value for zoning, seasonal regulations, and assessing potential catch loss due to MPA implementation.