Deep cleaning of alien and cryptogenic species records in the Greek Seas (2018 update)

This work presents a current (2018) annotated list of marine NIS and cryptogenic species in Greek marine waters. For this purpose, we updated information from previous lists, included new data from several new NIS and cryptogenic records and recent taxonomic studies, and followed current taxonomic modifications for the alien/cryptogenic status of several introduced species. Our extensive literature survey and revisions resulted in the exclusion of 61 species, which were included in previous lists, and the addition of 41 new alien species reported in the 2016–2018 period plus ten old NIS records. The current number of introduced species in Greek waters whose presence is not questionable includes 214 alien species and 62 cryptogenic species. Approximately 80% of the introduced species in Greek Seas consists of the taxa—in decreasing order—Mollusca, Polychaeta, Crustacea, Fishes, and Macroalgae. Nevertheless, a considerable increase in the number of NIS Bryozoa and Ascidiacea was observed within the last decade. Unaided natural dispersal of Lessepsian immigrants (57%) and transport-stowaways (36.7%) are the major pathways of introduction reported for Greek waters. However, with few exceptions (6.8% of species), the confidence level in assigning a pathway was medium to low. Several species reported from adjacent marine areas are expected to reach Greek waters within the next years. The intensification of underwater observations by citizen scientists combined with further research in hot spot areas, understudied habitats and overlooked taxa will significantly raise the number of NIS species in Greek waters. This study can serve as a basis that could greatly benefit from the coordination and harmonization of monitoring initiatives under international, EU and Regional Policies, and the compilation of new data from established monitoring programs, and rapid assessment surveys.JRC.D.2-Water and Marine Resource

A benthic macroinvertebrate size spectra index for implementing the Water Framework Directive in coastal lagoons in Mediterranean and Black Sea ecoregions

Size spectra show common patterns of variation among ecosystem types, functional guilds and taxonomic groups, as well as predictable responses to pressures. Here, we extend the size spectra approach to macroinvertebrate ecological status assessment in transitional waters, by developing, testing and validating a multi-metric index of size spectra sensitivity (ISS), which integrates size structure metrics with metrics describing the sensitivity of size classes to anthropogenic disturbance and species richness measures. The ability of different theoretical models of size spectra sensitivity to discriminate between undisturbed and disturbed ecosystems and levels of environmental stress was evaluated. We have used data on benthic macroinvertebrates within 12 Mediterranean and Black Sea transitional water bodies (i.e. coastal lagoons) from Italy, Albania, Greece, Bulgaria and Romania and compared the models’ efficiency through their pressure-impact response along organic load and enrichment gradients. Data from a thirteenth Mediterranean lagoon was used for validation purposes. Asymmetric models of size class sensitivity, assuming higher sensitivity of larger body size classes, were found to be more effective than symmetric models, with higher sensitivity of less common size classes, in distinguishing undisturbed from disturbed lagoons and lagoon stations. The ISS based on the asymmetric sensitivity model that was most efficient in identifying the anthropogenic impacts also showed significant dose–response relationships along environmental parameters describing the organic load and enrichment gradients. A scheme for the classification of Ecological Quality Status based on the macroinvertebrate ISS is proposed and validated. The validation procedure found that ISS is an effective and sensitive monitoring tool, easy to apply and to inter-calibrate among laboratories. Moreover, the tests performed here over a very large ecoregional area have proved the spatial robustness of the new index.JRC.H.5-Rural, water and ecosystem resource

EUSeaMap. A European broad-scale seabed habitat map

In order to most benefit from the potential offered by the European marine basins in terms of growth and employment (Blue Growth), and to protect the marine environment, we need to know more about the seafloor. European Directives, such as the MSFD, but also the Horizon 2020 roadmap explicitly called for a multi-resolution full coverage of all European seas including bathymetry, geology and habitats. The present work, following on a suite of past initiatives, has made a big step forward in this direction. It has first boosted the collation of existing maps from surveys by setting up a framework and a procedure to encourage people to submit their maps and data. This resulted in a more attractive EMODnet seabed habitat portal and a snowball effect with more and more people willing to join. However, collation will eventually come to an end and as new creations of seabed habitat maps are so complex and time-consuming, a cost-efficient way to meet the need for a full-coverage habitat map was found to be low-resolution maps and models to predict seafloor habitat types. The broad-scale map referred to as EUSeaMap has been created by this project and after the first two phases it now covers all European basins from the Barents Sea to Macaronesia and to the Black Sea. By harmonising mapping procedures - based on the EUNIS classification - and fostering a common understanding among seabed mappers in Europe, EUSeaMap provides today the community with a comprehensive, free and ready-to-use map that can find applications at regional scale for management and conservation issues. Tables and maps for all basins can be found in section 3 “Results and disciussions”. The project has played a key role in giving feedback to other EMODnet communities dealing with bathymetry, geology and biology, all essential data sources for the broad-scale map. It has also improved the understanding of the EUNIS habitat classification - with a focus on the Adriatic and the Black Sea - by better specifying transitions between classes based on benthic ground-truth data. It has fostered the development of oceanographic variables such as light, waves and currents that have a strong bearing on habitats. Finally it has also been instrumental in developing map confidence assessment methods that account for the broad spatial variation in data sources quality and for uncertain boundaries between habitat classes. The EUSeaMap methods are repeatable and ensure that the predictive maps can continue to be improved in the future, as a result either of EUNIS enhancements or increase in resolution. From today’s 250m resolution it is likely that new deliveries of enhanced source layers due to steady progress in oceanography and geophysics will enable constant refinement of the maps over time

EUSeaMap 2019, A European broad-scale seabed habitat map, technical report

EUSeaMap 2019 is the third iteration of EUSeaMap. All versions have been produced as part of the EMODnet Seabed Habitats project, which is one of several thematic lots in EMODnet. The project has brought together a European consortium of specialists in benthic ecology and seabed habitat mapping. The partners first collaborated in EMODnet phase 1 (2009-2012) to deliver a prototype predictive seabed habitat map in four trial basins (Greater North Sea, Celtic Seas, Baltic, Western Mediterranean). This predictive model was named EUSeaMap (Cameron and Askew, 2011). In EMODnet Phase 2 (2012-2016), the consortium extended EUSeaMap coverage to all European regions (Populus et al, 2017). In the new version, the spatial coverage was extended further North in order to include the Barents Sea. The spatial detail was substantially improved. This was made possible by improvements to the physical predictor variables created by the other EMODnet lots which are the input data to the EUSeaMap model. A substantial revision of the map creation process has also been carried out in order to make it more reproducible. This document describes all these modifications which have led to the elaboration of EUSeaMap 2019