Seafloor macrolitter as a settling platform for non-native species: A case study from UK waters

• Published in: Marine pollution bulletin 2024-07, Vol.204, p.116499, Article 116499
• Main Authors: Barry, P.J., Silburn, B., Bakir, A., Russell, J., Tidbury, H.J.
• Format: Article
• Language: English
• Subjects: Marine litter; Non-native species; Polymer; Settlement patterns; United Kingdom
• ISSN: 0025-326X; 1879-3363; 1879-3363
• DOI: 10.1016/j.marpolbul.2024.116499

Marine litter is increasingly recognised as a vector for the spread of non-native species (NNS). However, our understanding of its role in the propagation of NNS in UK waters remains limited. As part of the Clean Seas Environmental Monitoring Programme, we opportunistically analysed seafloor macrolitter items trawled from various locations around the coast of England and Wales and examined each for the presence of NNS. Of the 41 litter items analysed, we identified a total of 133 taxa, including two non-native and four cryptogenic species. This confirms that NNS are settling on seafloor macrolitter in UK waters and that these can be detected using morphological taxonomic analysis. Furthermore, we propose a methodology to classify litter based on size, rugosity and polymer/material type to explore whether there were detectable patterns governing community composition and litter characteristics. This exploratory investigation provides evidence to inform future risk assessments of NNS vectors and pathways. •We analysed seafloor litter samples for the presence of non-native species•We found two non-native species on seafloor litter from around the UK•We found four cryptogenic species on seafloor litter from around the UK•We describe a methodology for analysing the litter, by looking at the material composition (e.g., polymers), surface texture and size•We discuss some of the major groups we have found on the litter and how it relates to previous studies