Cetacean presence and distribution in the central Mediterranean Sea and potential risks deriving from plastic pollution

Highlights: • Eight cetacean species were recorded in the Sicilian and Sardinian Channels. • Cetacean long-term presence was estimated, and suitable habitats were identified. • A spatially explicit risk assessment analysis for plastic threat was performed. • Results represent a great improvement for cetacean knowledge in this region. • Findings can contribute to design effective conservation management strategies. The Sardinian and Sicilian Channels are considered hotspots of biodiversity and key ecological passages between Mediterranean sub-basins, but with significant knowledge gaps about marine mammal presence and potential threats they face. Using data collected between 2013 and 2019 along fixed transects, inter and intra-annual cetacean index of abundance was assessed. Habitat suitability, seasonal hot spots, and risk exposure for plastic were performed using the Kernel analysis and the Biomod2 R-package. 661 sightings of 8 cetacean species were recorded, with bottlenose and striped dolphins as the most sighted species. The north-eastern pelagic sector, the coastal waters and areas near ridges resulted the most suitable habitats for these species. The risk analysis identified the Tunis, Palermo, and Castellammare gulfs and the Egadi Island as areas of particular risk of plastic exposure. The study represents a great improvement for cetacean knowledge in this region and contributes to the development of effective conservation strategies.