Living on the Extinction Edge: Resilience to Fishing and Rebound Potential of the Mediterranean Elasmobranchs

Abstract

Mediterranean elasmobranchs are experiencing significant declines due to intense fishing activities, making the region a global hotspot for elasmobranch conservation concerns. These declines are worsened by limited fisheries data, constraining stock assessments and evidence-based management. Demographic models based on life history parameters (e.g., survival rate, age-at-maturity, litter size and longevity) offer critical alternatives for estimating population productivity in data-poor contexts. In this study, we estimated the intrinsic rate of population increase ((Formula presented.)) for 82 stocks across 51 species of Mediterranean sharks and rays to assess their relative capacity for recovery under hypothetical sustainable exploitation scenarios. Using demographic modelling and updated life history data, we provide a comparative analysis of species-specific productivity and identify those with the lowest recovery potential. Many IUCN-listed threatened species exhibited very low rebound potential, highlighting their vulnerability to fishing. Significant data gaps, especially for pelagic and deep-sea taxa, underscore the need for targeted life history research. Our results also showed how the rebound potential can provide valuable insight for data-deficient species, supporting informed assessments with limited biological input. Furthermore, we confirmed that age-at-maturity is a valid proxy of (Formula presented.) when other parameters are unavailable. This study delivers a comprehensive, regional-scale productivity baseline for Mediterranean elasmobranchs, providing essential input for prioritising species-specific conservation actions, guiding fishery policy development and improving regional compliance with international conservation frameworks. By addressing critical data limitations, our approach enhances the scientific foundation necessary for the sustainable management and recovery of shark and ray populations in the Mediterranean Sea.