Corrigendum: Analysis of Long-Term Changes in a Mediterranean Marine Ecosystem Based on Fishery Landings

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Erratum to: Governance and Sustainability of Responsible Research and Innovation Processes

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The second workshop on lists of commercial fish and shellfish species for reporting of MSFD D3 (WKD3Lists2)

WKD3Lists2 created lists of regionally relevant commercial fish and shellfish species (and higher order taxa) for the use of Article 8 reporting by EU member states under Descriptor 3 of the Marine Strategy Framework Directive (MSFD). The regional taxa lists were based on landings data from the Fisheries Dependent Information data base (FDI) provided by EU member states and compiled by the Joint Research Centre (JRC). The taxonomy of landings data was consolidated by regional experts and the consolidated data were combined to obtain absolute and proportional landing weights and values for each (sub)re-gion, which were used to apply dual (weight and vale) selection thresholds to compile (sub)re-gional D3-taxa-lists. Regional D3-taxa-lists were produced for two MSFD regions (Baltic Sea & Black Sea) and eight MSFD subregions: The Greater North Sea, Celtic Seas, the Bay of Biscay and Iberian Coast, Mac-aronesia, Western Mediterranean, the Ionian Sea & Central Mediterranean, the Adriatic Sea and the Aegean-Levantine Sea. To exclude taxa with very low landing weights or value from the final lists, two types of thresh-olds (cumulative and minimum) with differing cut-off values were evaluated (90%, 95%, 98% and 99% for cumulative and 0.1% and 1% for minimum thresholds). Depending on the cut-off value, the number of taxa included varied substantially and in most (sub)regions the application of thresholds reduced the initial number of taxa by more than 50%. WKD3Lists2 did not recommend any threshold type or cut-off value to be applied generically in all (sub)regions, but identified trade-offs between inclusiveness and parsimony of relevant con-tent i.e. higher cut-off values will lead to longer lists including many taxa with relatively low landings weights/values. In some (sub)regions, thresholds with lower cut-off values (90% to 95%) were considered feasible by regional experts (Mediterranean subregions, Bay of Biscay and Iberian Coast, Macaronesia), whereas in other MSFD (sub)regions cut-off values in the range of 98-99% were considered as appropriate (Baltic Sea, Greater North Sea, Celtic Seas). The regional D3-taxa lists by WKD3Lists2 were created without considering the availability of data or assessments i.e. many species are included, for which no assessment information is avail-able. WKD3Lists2 decided on this approach because a representative selection of commercially targeted taxa was considered to indicate knowledge and data gaps in current data collection and assessment schemes. Regional species lists shall be used by EU member states for the national reporting of D3. Stocks and species from the regional lists shall be considered by member states, and additional stocks/species can be added where appropriate (e.g. those stocks/species of national or local of importance that do not appear on the regional lists). x WKD3Lists2 discussed and compiled recommendations on how Member States can complement the regional lists of D3-taxa. A key recommendation is to maintain taxa reported in 2018 under D3, even if they are not part of the regional D3-taxa list for 2024. Wherever possible, Member States should report on stock level. WKD3Lists2 also discussed linkages between D1 and D3-reporting of commercial taxa.info:eu-repo/semantics/publishedVersio

Technical guidance on monitoring for the Marine Stategy Framework Directive

The Marine Directors of the European Union (EU), Acceding Countries, Candidate Countries and EFTA Countries have jointly developed a common strategy for supporting the implementation of the Directive 2008/56/EC, “the Marine Strategy Framework Directive” (MSFD). The main aim of this strategy is to allow a coherent and harmonious implementation of the Directive. Focus is on methodological questions related to a common understanding of the technical and scientific implications of the Marine Strategy Framework Directive. In particular, one of the objectives of the strategy is the development of non-legally binding and practical documents, such as this technical guidance on monitoring for the MSFD. These documents are targeted to those experts who are directly or indirectly implementing the MSFD in the marine regions. The document has been prepared by the Joint Research Centre of the European Commission (JRC) with the contribution of experts from Member States, Regional Seas Conventions and ICES and following consultation of the Working Group on Good Environmental Status.JRC.H.1-Water Resource

Coding Early Naturalists' Accounts into Long-Term Fish Community Changes in the Adriatic Sea (1800–2000)

The understanding of fish communities' changes over the past centuries has important implications for conservation policy and marine resource management. However, reconstructing these changes is difficult because information on marine communities before the second half of the 20th century is, in most cases, anecdotal and merely qualitative. Therefore, historical qualitative records and modern quantitative data are not directly comparable, and their integration for long-term analyses is not straightforward. We developed a methodology that allows the coding of qualitative information provided by early naturalists into semi-quantitative information through an intercalibration with landing proportions. This approach allowed us to reconstruct and quantitatively analyze a 200-year-long time series of fish community structure indicators in the Northern Adriatic Sea (Mediterranean Sea). Our analysis provides evidence of long-term changes in fish community structure, including the decline of Chondrichthyes, large-sized and late-maturing species. This work highlights the importance of broadening the time-frame through which we look at marine ecosystem changes and provides a methodology to exploit, in a quantitative framework, historical qualitative sources. To the purpose, naturalists' eyewitness accounts proved to be useful for extending the analysis on fish community back in the past, well before the onset of field-based monitoring programs

Workshop to scope and preselect indicators for criterion D3C3 under MSFD decision (EU) 2017/848 (WKD3C3SCOPE)

The workshop to scope and preselect indicators for Descriptor 3 criterion 3 under MSFD Commission Decision (EU) 2017/848 (WKD3C3SCOPE) provided a platform for experts from the EU member states and relevant regional bodies to meet and support development and progress the assessment methodology, based on a request by the EC (DGENV). WKD3C3SCOPE is the first of a series of three workshops (WKD3C3THRESHOLDS and WKSIMULD3) to provide guidance in relation to operational indicators for MSFD D3C3. The workshop was organized as a series of presentations with intermittent group discussions. On the first day of the workshop the participants discussed what defines a ‘healthy population structure’ for species with different life history traits (ToR a). During the following days, the group discussed and identified relevant D3C3 indicators (ToR b) and developed criteria to select among the identified D3C3 indicators to allow further testing and setting of thresholds at WKD3C3THRESHOLDS (ToR c). The participants found that overall, healthy fish stocks are characterized by high productivity, wide age and size structuring in the population, and the ability to quickly recover from disturbances. The groups noted that environmental factors, along with stock biomass and fishing pressure, influence the productivity and health of a stock, with environment playing a particularly large role in the recruitment of short-lived stocks. It was suggested that the age structure of a stock might be more relevant for evaluating the health of long-lived stocks. However, it was acknowledged that not all stocks have sufficient data to evaluate all proposed indicators, and a single indicator is unlikely to suffice for all stocks. Data availability, species- specific factors and regional or sub-regional variation are thus also important considerations. In relation to ToR b, the participants presented their work on potential indicators including: recruitment time-series, proportion of fish larger than the mean size of first sexual maturation, F rec/Fbar, length distribution L 90, relative proportion of old fish above A 90, indicators of spawner quality, and SSB/R. A discussion on pros/cons, benefits to the population of high or low indicator values, benefits supported by empirical evidence, applicability to data-poor stocks and benefits supported by simulation/theoretical considerations followed the presentations. Finally, in relation to ToR c, the difficulty emerged in ranking the indicators alone without considering the data used to estimate them and a new set of evaluation criteria for use in WKD3C3THRESHOLDS were defined. Based on the outputs of the meeting a list of indicators to be further evaluated has been drafted, which also emphasizes the stocks for which studies have empirically demonstrated effects on productivity. In addition to the listed indicators, indicators of genetic diversity and proportion of fish with parasite infestation were mentioned but to the knowledge of the participants, widespread data for these are currently not publicly available.info:eu-repo/semantics/publishedVersio

Top predator status and trends: ecological implications, monitoring and mitigation strategies to promote ecosystem-based management

The conservation and management of marine ecosystems hinge on a comprehensive understanding of the status and trends of top predators. This review delves into the ecological significance of marine top predators, examining their roles in maintaining ecosystem stability and functioning through an integrated analysis of current scientific literature. We first assess the efficacy of various monitoring methods, ranging from traditional field observations to cutting-edge technologies like satellite tracking and environmental DNA (eDNA) analysis and evaluating their strengths and limitations in terms of accuracy, spatial coverage, and cost-effectiveness, providing resource managers with essential insights for informed decision-making. Then, by synthesizing data from diverse marine ecosystems, this study offers a comprehensive overview of the trends affecting top predator populations worldwide. We explore the multifaceted impacts of human activities, climate change, and habitat degradation on the abundance and distribution of these key species. In doing so, we shed light on the broader implications of declining top predator populations, such as trophic cascades and altered community structures. Following a thorough assessment of successful strategies for reversing the decline of top predators, a compilation of recommendations is presented, encompassing effective governance interventions. A crucial aspect of effective ecosystem-based management is the implementation of robust monitoring strategies. Mitigation measures are imperative to reverse the adverse impacts on marine top predators. We present a comprehensive array of mitigation options based on successful case studies. These include the establishment of marine protected areas, the enforcement of fisheries regulations, and the promotion of sustainable fishing practices. We deepen the synergies between these strategies and their potential to mitigate human-induced stressors on top predator populations to safeguard their pivotal role in maintaining marine ecosystem structure and function. By examining marine top predators’ ecological significance, analyzing population trends, discussing monitoring techniques, and outlining effective mitigation strategies, we provide a comprehensive resource for researchers, policymakers, and stakeholders engaged in fostering ecosystem-based management approaches. We conclude that integrating these insights into current management frameworks will be essential to safeguard both top predators and the broader marine environment for future generations

Ecological stages of the Venice Lagoon analysed using landing time series data

The time series of landings in the Venice Lagoon from 1945 to 2001 were analysed with the aim of explaining the ecosystem changes occurred. The comparative analysis of the total landings and mean Trophic Level (mTL) time series allowed to identify four different stages in the lagoon ecosystem. The first period, from 1945 to 1973, was characterised by increasing trends in the landings and their mTL. The second one, from 1974 to 1989, showed a decrease in the landings but still an increase in the mTL. The third period, from 1990 to 1998, had again a positive trend in the landings, but the mTL showed a sharp decline. After 1998, a slight decreasing trend in both mTL and landings was observed: the analyses of the artisanal fishery landings only date back to 1995 this effect. The presence of four distinct periods was also confirmed by the analysis of the trends of other indices estimated using landings data: the Fishing in Balance index (FiB), the Trophic Efficiency (TE) and the Pelagic on Demersal landings ratio (P/D). In the first period, the increasing fishing pressure, along with no evidence of ecosystemcrisis, suggested that an increased nutrient dischargewas supporting it; analogously, the bottom-up effects had driven the dynamics of the ecosystem also in the second period, when the decrease in nutrient loads caused a shift of the primary producers fromplanktonic tomacrobenthic. The spreading of theManila clam, a non-native species, and the development of its massive mechanical exploitation have been the main forces driving the ecosystem during the third period, forwhich, however, no signs of criseswere detected. The fourth period showed evidence of the ‘‘fishing down the food web’’ effect. Possible causes of such an effect were investigated and allowed us to conclude that not overfishing, but the effects ofmechanical harvesting of theManila clamhad caused relevant impacts on habitat and benthic communities, concluding that the present level of exploitation of the stock ofManila clamis not sustainable in the long term. Our findings were also compared with the general evolution of enclosed seas, subjected to high nutrient loads, fishing pressure and invasion by non-native species

The Biodiversity of the Mediterranean Sea: Estimates, Patterns, and Threats

The Mediterranean Sea is a marine biodiversity hot spot. Here we combined an extensive literature analysis with expert opinions to update publicly available estimates of major taxa in this marine ecosystem and to revise and update several species lists. We also assessed overall spatial and temporal patterns of species diversity and identified major changes and threats. Our results listed approximately 17,000 marine species occurring in the Mediterranean Sea. However, our estimates of marine diversity are still incomplete as yet—undescribed species will be added in the future. Diversity for microbes is substantially underestimated, and the deep-sea areas and portions of the southern and eastern region are still poorly known. In addition, the invasion of alien species is a crucial factor that will continue to change the biodiversity of the Mediterranean, mainly in its eastern basin that can spread rapidly northwards and westwards due to the warming of the Mediterranean Sea. Spatial patterns showed a general decrease in biodiversity from northwestern to southeastern regions following a gradient of production, with some exceptions and caution due to gaps in our knowledge of the biota along the southern and eastern rims. Biodiversity was also generally higher in coastal areas and continental shelves, and decreases with depth. Temporal trends indicated that overexploitation and habitat loss have been the main human drivers of historical changes in biodiversity. At present, habitat loss and degradation, followed by fishing impacts, pollution, climate change, eutrophication, and the establishment of alien species are the most important threats and affect the greatest number of taxonomic groups. All these impacts are expected to grow in importance in the future, especially climate change and habitat degradation. The spatial identification of hot spots highlighted the ecological importance of most of the western Mediterranean shelves (and in particular, the Strait of Gibraltar and the adjacent Alboran Sea), western African coast, the Adriatic, and the Aegean Sea, which show high concentrations of endangered, threatened, or vulnerable species. The Levantine Basin, severely impacted by the invasion of species, is endangered as well