could also be inferred from acoustic data in sperm whales. Research on cetaceans in the Pelagos Sanctuary also revealed an unexpected genetic separation between fin whales occurring in the Ligurian Sea and their North Atlantic conspecifics. Studies based on mtDNA analysis show that the Mediterranean Risso’s Dolphin population has been found to be genetically differentiated from the one inhabiting the waters of Azores, United Kingdom and from other oceanic populations. There is also some evidence of a possible Mediterranean subpopulation. Also surprising diving capabilities of fin whales and long-finned pilot whales have been highlighted; equipped with time-depth recorders, they showed to be able to dive, respectively, to depths >470m and >820m. The long-term photo-identification study of fin whales in the Pelagos Sanctuary (1990-present) points to the existence of a persistent site fidelity and reaffirms the importance of this area as a major feeding ground and critical habitat for the Mediterranean subpopulation, providing baseline data for targeted conservation and mitigation measures. A satellite telemetry research programme, funded by the Italian Ministry of the Environment and carried out in collaboration with the International Whaling Commission (IWC), the University of Siena, ISPRA, and the Alaska Fisheries Science Center in Seattle (USA), investigated fine-scale habitat use, movements and migration patterns of fin whales in the Pelagos Sanctuary in September 2012. Results indicate that tagged fin whales remained in the Pelagos Sanctuary summer feeding grounds until late autumn, much longer than expected, most likely due to the unusual climate conditions triggering prolonged productivity and whale feeding activity. Satellite tracking also revealed that the feeding habitat of fin whales extends substantially to the West of the Pelagos Sanctuary’s boundaries, well into the Gulf of Lion and into Spanish waters. Fine scale associations with oceanographic features and potential feeding habitats within the Sanctuary were also observed. Short-term responses of fin whales in the Pelagos Sanctuary to approaching vessels have been described through passive plotting of the whales’ tracks with laser range-finder binoculars. Avoidance strategies were observed under disturbance: travel at increased speed, reduction of the time spent at the surface, and switching from supposed feeding behaviour to travelling. A pilot project aimed at investigating the potential use of a medium fixed-wing aircraft system (RPAS) for monitoring cetaceans, as an alternative method to conventional aerial manned surveys, was launched in 2022. Thanks to a long-lasting collaboration with the Italian Coast Guard, the RPAS, provided by the REACT consortium