Seasonal patterns of floating macro-litter across the Western Mediterranean Sea: a potential threat for cetacean species

摘要: Marine litter is a major form of pollution in the Mediterranean, but despite legislative requirements, additional information still needed to evaluate basin-scale amounts, trends, and potential threats for biota, especially Habitats Directive listed species, such as cetaceans. Through repeated sampling floating macro-litter along fixed transect between Spain Italy, this study provided detailed data within four marine sectors Western Mediterranean Sea, characterized by seasonal variability oceanographic/ecological conditions anthropogenic pressure. Moreover, we identified areas overlap high density plastic cetacean sightings. Litter was composed more than 65%, with diverse compositions occurring Balearic Sardinian Sea compared semi-enclosed Bonifacio Tyrrhenian sectors. The average amount ranged 1.9 2.8 items km−2 reached highest values spring/summer all basins, suggesting relationship increasing touristic maritime activities, both coastal offshore waters. showed higher amounts larger accumulation plastic, likely due combination multiple sources oceanographic processes influencing distributional patterns. Cetacean sightings were recorded fin whale (Balaenoptera physalus) striped dolphin (Stenella coeruleoalba) most frequent species. presence cetaceans densities emerged mostly during sectors, other specific exposure identified, indicating need dynamic definition threat.