A multi-faceted approach to assess the sustainability of diving tourism: the case of Rome's MPA

Marine Protected Areas (MPAs) are crucial for conserving biodiversity, ensuring the sustainable use of marine resources, and hosting most diving destinations. Several studies show that diving activities can damage marine life. The present study aimed to assess the disturbance of SCUBA diving activities within the Secche di Tor Paterno MPA through a multi-faceted approach. We considered three levels of analysis. Firstly, to identify the factors influencing the number of diver-substrate interactions, we analysed frequentation of the MPA, behaviour and profiles of visiting divers. Additionally, we identified the hotspots, i.e., the areas most subject to physical disturbance, through small-scale spatial analysis. Finally, we analysed the potential impacts of diving tourism on the structure of benthic communities, using bio-indicator organisms sensitive to such disturbances. A moderate level of frequentation was reported. The mean interaction rate was quantified as 0.13 interactions min^(-1), influenced primarily by diving experience and camera use. Only 1 % of these interactions were recorded as physical damage to benthic organisms. The hotspots coincided with areas attractive to underwater photographers. Despite various diver-substrate interactions, no significant changes in bio-indicator species diversity were observed, confirming depth as the most significant factor explaining the variations in benthic community diversity among dive sites. The multi-faceted approach used in this study provided a comprehensive view of touristic diving disturbance in the MPA, serving as a starting point for improving interventions and conservation strategies in an adaptive management framework.