tools4MCDA: An R-Package to estimate spatial fishing effort, weight and value of landings using multi-criteria decision analysis

Effective spatial monitoring of fishing activities is often limited by the absence of vessel positioning systems, particularly in fleet segments <12m overall length. Small-scale fisheries (SSF) are a prominent example, particularly in the Mediterranean, where they play a significant socio-economic role but remain underrepresented in management due to the lack of spatially explicit data. To address this gap, we developed tools4MCDA, an open-source R package that implements a refined Multi-Criteria Decision Analysis (MCDA) approach. The tool integrates diverse open source datasets, including the EU Fleet Register and Fisheries Dependent Information (FDI), alongside environmental/anthropogenic criteria to estimate spatial patterns of fishing effort and landings (weight and economic value). Its flexible design allows adaptation to different contexts and fleet segments, including gear types beyond SSF, with minor modifications. The tools4MCDA accommodates varying data availability, enabling estimations even in the absence of species distribution or positioning data. In addition to its analytical capabilities, it generates tables and maps across multiple spatiotemporal scales and by métier. To demonstrate its application, the method was applied to a Greek case study, generating spatially explicit estimates of SSF effort and landings by species. By addressing key data limitations and enabling flexible integration of several datasets, the tool enhances the capacity for ecosystem-based fisheries management and spatial planning. Ultimately, it contributes to the more effective inclusion of various fishing sectors, including small-scale and under-monitored fleets, within broader sustainability and policy frameworks.