Diving into ecosystem value: a travel cost assessment of shark-related tourism in the mediterranean sea

This study represents the first attempt to apply the Travel Cost Method to scuba diving tourism associated with shark presence in the Mediterranean Sea, focusing on the Banco di Santa Croce—a marine area of high ecological value located in the Gulf of Naples (Italy), known for its iconic elasmobranch species. In the absence of official databases on the Italian diving population, the reference universe was reconstructed through engagement with the main national diving associations and the use of other official sources. Based on data collected through a survey of 137 divers conducted between November 2024 and February 2025, the estimated average consumer surplus amounts to approximately €519 per visit, resulting in an annual aggregate recreational value of about €1 million. This value highlights the significant, often unaccounted-for economic contribution of recreational activities linked to marine biodiversity and underscores the need to integrate the assessment of ecosystem services into public policy decisions. In a coastal context under high anthropogenic pressure, such as the Gulf of Naples, the results provide a solid economic basis supporting more sustainable marine management policies oriented towards biodiversity conservation. The study contributes to the growing literature on marine natural capital and proposes a replicable methodological model for the evaluation of ecosystem services in data-limited contexts.