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Report2021Open access

Marine Strategy Framework Directive- Descriptor 2, Non-Indigenous Species : delivering solid recommendations for setting threshold values for non-indigenous species pressure on European seas

Tsiamis, Konstantinos; Palialexis, Andreas; Connor, David; Antoniadis , Stavros; Bartilotti, Catia; Bartolo, Angela G.; Berggreen, Ulrik Christian; Boschetti, Simona; Buschbaum, Christian; Canning-Clode, Joao; Carbonell, Aina; Castriota, Luca; Corbeau, Clemence; Costa, Ana C.; Cvitkovic, Ivan; Despalatovic, Marija; Dragicevic, Branko; Dulcic, Jakov; Fortič, Ana; Francé, Janja;
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Marine Non-Indigenous Species (NIS)are animals and plants introduced accidently or deliberately into the European seas, originating from other seas of the globe. About 800 marine non-indigenous species (NIS)currently occurin the European Union national marine waters, several of which have negative impacts on marine ecosystem services and biodiversity. Under the Marine Strategy Framework Directive (MSFD) Descriptor 2 (D2), EU Member States(MSs)need toconsider NIS in their marine management strategies. The Descriptor D2 includes one primary criterion (D2C1: new NIS introductions),and two secondary criteria (D2C2and D2C3). The D2 implementation is characterized by a number of issues and uncertaintieswhich can beapplicable to the Descriptor level (e.g. geographical unit of assessment, assessment period, phytoplanktonic, parasitic, oligohaline NIS, etc.), to the primary criterion D2C1 level (e.g. threshold values, cryptogenic, questionable species, etc), and to the secondary criteria D2C2 and D2C3. The current report tackles these issues and provides practical recommendations aiming at a smoother and more efficient implementation of D2 and its criteria at EU level. They constitute a solid operational output whichcan result in more comparable D2 assessments among MSsand MSFD regions/subregions. When it comes to the policy-side, the current report callsfor a number of different categories of NIS to be reported in D2 assessments, pointing the need for the species to be labelled/categorised appropriately in the MSFD reporting by the MSs.These suggestions are proposed to be communicated to the MSFD WorkingGroup of Good Environmental Status (GES)and subsequently to the Marine Strategy Coordination Group (MSCG) of MSFD. Moreover, they can serve as an input for revising the Art. 8 Guidelines.

Published in

EUR (Luxembourg)
2021, number: 30640ISBN: 978-92-76-32257-3
Publisher: Publications Office of the European Union