Spatial risk analysis of floating marine macro litter along the Western Sicilian coast: Overlap with bottlenose dolphin and seabird hotspots.

Abstract

Marine litter is known to be a major stressor in coastal marine habitats. Therefore, the aim of this study was to identify the areas where species could be most threatened by floating marine macro-litter (FML) The composition and density distribution of FML along the waters of the Agrigento province was monitored from 2019 to 2021, together with the density distribution for the protected species Tursiops truncatus, Hydrobates pelagicus melitensis, Calonectris diomedea, and Puffinus yelkouan.. The areas where marine litter poses the biggest threat to these species were identified by overlapping the core areas of their distribution with that of FML. The results showed that FML’s was mainly composed of plastics (90 %). There was a high degree of overlap between FML’s core area and focal species: 65 % for bottlenose dolphins, 76,3 % for the European storm-petrel, and 85,1 % for the shearwaters. Our findings highlight a key area of about 54 km2, within the 25–70 m depth, where the highest presence of protected species and FML was observed. The high degree of overlap of the species and FML core-areas underlines the need to enact specific management measures.