Refined baseline inventories of non-indigenous species (NIS) are set per European Union Member State (MS), in the context of the Marine Strategy Framework Directive (MSFD). The inventories are based on the initial assessment of the MSFD (2012) and the updated data of the European Alien Species Information Network, in collaboration with NIS experts appointed by the MSs. The analysis revealed that a large number of NIS was not reported from the initial assessments. Moreover, several NIS initially listed are currently considered as native in Europe or were proven to be historical misreportings. The refined baseline inventories constitute a milestone for the MSFD Descriptor 2 implementation, providing an improved basis for reporting new NIS introductions, facilitating the MSFD D2 assessment. In addition, the inventories can help MSs in the establishment of monitoring systems of targeted NIS, and foster cooperation on monitoring of NIS across or within shared marine subregions.

Millions of tons of solid waste, mostly plastics, are annually dumped into the oceans, posing a major 21st-century environmental threat. Commercial shipping and ocean gyres exacerbate pollution on remote islands, resulting in the widespread presence of microplastics throughout the marine environment. Most of this pollution is plastics, and its fragmentation originates from microplastics (particles smaller than 5 mm). These debris are ubiquitous throughout the marine environment, dispersed among beaches, estuaries, on the water surface, and even on the seafloor. This study was carried out on São Miguel Island, Azores, where sediment samples were collected and analysed for microplastic (MP) abundance and dimension across eight areas covering the entire coastline of the island. Each area was divided into four sites along an inland–coastal gradient, from the stream to the ocean (upstream, downstream, coastal, and submerged marine sediments), following a nested design approach. In addition to this first method, 15 beaches, spread along the island’s shore, were also tested and compared. Fibres were the most common type of microplastic, with varying levels of abundance across different locations. Abundance generally increased closer to the coast, but there were occasional instances of high upstream concentrations due to heavy rains, which then accumulated near coastlines and beaches. This study revealed an important local MP source from an apparently pristine touristic region which, aligned with other recent findings, unveils an important and silent pollution issue potentially affecting oceanic islands that should be seriously addressed in future studies and raise concern for litter management and mitigation and environmental awareness actions.

Acrothamnion preissii is an invasive species in the Mediterranean Sea, and is listed among the 100 worst non-indigenous species. In July and August 2009, this non-native red macroalga was found for the first time in the Azores (on Santa Maria), and this represents the first record of this species in the Atlantic. Here, we describe the establishment of this invasive species in the Atlantic. In recent surveys, A. preissii displayed an invasive behaviour. As suggested for the Mediterranean Sea, hull fouling is the most likely vector for its introduction into the Azores.