The Integrated Assessment as the main goal for achieving an Ecosystem Approach to Management in the Western European Shelf Seas

Providing regional integrated ecosystem assessments (IEA) is a key challenge identified in the ICES Strategic Plan (2014-2018). IEAs are seen as a fundamental link between advice and ecosystem science inachieving Ecosystem Based Management (EBM).While EBM is not a new concept, difficulties in achieving such an ambitious goal have been highlighted by the extensive work conducted in this area. The implementation of new regulation policies, such as the Marine Strategy Framework Directive (MSFD) and the reformed Common Fisheries Policy (CFP) in Europe,have challenged the scientific community to rapidly react despite these difficulties and provide scientific advice to support management decisions concerning these policies. RegionalICES groups have been tasked with developing methods and tools for IEA in their corresponding ecoregions; this is the case of the Working Group on Ecosystem Assessment of Western European Shelf Seas (WGEAWESS). The role of this group is to implement, and test tools and methods for the advisory process, focusing on the North Atlantic European continental shelf, including Celtic Seas, Bay of Biscay and Iberian Waters. In this presentation we show the progress made within this WG during its initial three years of activity, in relation to some of the terms of reference already addressed. An adaptation of the ODEMM framework has been selected as a tool for identifying a) links between components, processes, pressures and states, and b) gaps in data availability and indicator implementation. Some preliminary results of a first IEA exercise will also been shownwith emphasis onthe MSFD descriptors D1 (biological diversity) and D4 (food webs)

Interim Report of the Working Group on Ecosystem Assessment of Western European Shelf Seas

The ICES Working Group on Ecosystem Assessment of Western European Shelf Seas (WGEAWESS) meeting was held in Lisbon (Portugal), on 24–28 April 2017. The meeting was attended by 8 participants from 4 countries and chaired by Steven Beggs, Northern Ireland (UK). This was the first year of the new 3-year Terms of Reference (ToR) for WGEAWESS. The main activities for the group at the 2017 meeting were to discuss progress and further development of work towards the ToRs a) Continue metadata compilation for all ecosystem components available for IEA development, b) Continue evaluation of data and trends for a regional Integrated Ecosystem Assessment (IEA). Identify ecosystem trends relevant to stock assessment and management. As an outcome of specific objectives to integrate the activities of WGEAWESS with sister IEA groups, the meeting was held back to back with both the ICES/HELCOM Working Group on Integrated Assessments of the Baltic Sea (WGIAB) and the Working Group on Comparative Analyses between European Atlantic and Mediterranean marine ecosystems to move towards an Ecosystem-based Approach to Fisheries (WGCOMEDA). This back to back meeting had many advantages and provided much opportunity for group integration and future collaboration

Influence of seasonal variability on the trophic structure of pelagic communities

Seasonal variations in hydrodynamic conditions play a critical role in prey availability at the base of the food web and thus have implications for trophic interactions at higher trophic levels. Here we use the combination of stomach content analysis (SCA) and stable isotope analysis (SIA) to investigate predator-prey interactions and trophic structure of the pelagic fish community of the Bay of Biscay (BoB) in spring and late summer of 2020 and 2021. We found that trophic guilds were more influenced by intra-specific affinities rather than seasonal variability. Main prey for the pelagic fish comprised a set of species belonging to different trophic positions (TPs), from low TP class Thaliacea (salps) to mid TP Engraulis encrasicolus. Vertically migrating meso- and macrozooplankton (mainly copepods and krill) also played an important role as food source for the pelagic fish community showing high trophic overlap among most of species. No differences were detected between the trophic structure in spring and late summer with fish, squids and chaetognaths at the top TPs, whereas krill, meso-zooplankton and salps had the lowest values. However, the TPs estimated using both SCA and SIA approaches were consistently lower in spring, likely due to higher densities and, thus, low TP prey availability in spring. When analyzing ontogenic changes in TPs with predator’s size, significant and positive relationships were found when TP was estimated using SIA but not when using SCA. Overall, our results reveal new insights into the seasonal trophic dynamics of the pelagic fish community of the BoB

In support of the IOTC ecosystem report card: Advances in monitoring the impacts on and the state of the “foodweb and trophic relationships” ecosystem component

In support of the development of the ICCAT Ecosystem Report Card, this paper addresses the “foodweb/trophic relationships” ecosystem component. Specifically, it contributes towards developing the following elements: (1) we describe what this component means in the context of ICCAT species and fisheries and the importance of monitoring it; (2) we describe the role of ecological indicators and ecosystem models in monitoring this ecosystem component; (3) we present a list of candidate ecological indicators that could be estimated to monitor this component; (4) we discuss the main challenges in monitoring this ecosystem component and indicator development; and finally (5), we draft a work plan to guide our future work. We invite the ICCAT community and others to contribute towards the development of ecological indicators and ecosystem models to monitor this ecosystem component. If interested, contact the corresponding authors to find out how you can contribute to this initiative

In support of the ICCAT ecosystem report card: advances in monitoring the impacts on and the state of the “foodweb and trophic relationships” ecosystem component.

In support of the development of the ICCAT Ecosystem Report Card, this paper addresses the “foodweb/trophic relationships” ecosystem component. Specifically, it contributes towards developing the following elements: (1) we describe what this component means in the context of ICCAT species and fisheries and the importance of monitoring it; (2) we describe the role of ecological indicators and ecosystem models in monitoring this ecosystem component; (3) we present a list of candidate ecological indicators that could be estimated to monitor this component; (4) we discuss the main challenges in monitoring this ecosystem component and indicator development; and finally (5), we draft a work plan to guide our future work. We invite the ICCAT community and others to contribute towards the development of ecological indicators and ecosystem models to monitor this ecosystem component. If interested, contact the corresponding authors to find out how you can contribute to this initiative.Versión del editor

Selecting ecosystem indicators for fisheries targeting highly migratory species: An EU project to advance the operationalization of the EAFM in ICCAT and IOTC

Several international legal agreements and guidelines have set the minimum standards and key principles to guide the implementation of an ecosystem approach to fisheries management (EAFM). However, the implementation of an EAFM in tuna Regional Fisheries Management Organizations (RFMOs) has been patchy and lack a long-term plan, vision and guidance on how to operationalize it. The Specific Contract N0 2 “selecting ecosystem indicators for fisheries targeting highly migratory species-” (SC02 project) under the Framework Contract - EASME/ EMFF/2016/008 provisions of Scientific Advice for Fisheries Beyond EU Waters- addresses several scientific challenges and provides insights to support the implementation of an EAFM through collaboration and consultation with the International Commission for the Conservation of Atlantic Tunas (ICCAT) and the Indian Ocean Tuna Commission (IOTC). Specifically, this project first highlights properties of success and best practices from other regions of the world in operationalizing the ecosystem approach that potentially could be transferred to ICCAT and IOTC. Second, it delivered a list of potential ecosystem indicators of relevance to tuna RFMOs (ICCAT and IOTC) that are suitable to track the impacts of fisheries targeting tuna and tuna-like species on the broader pelagic ecosystem. Third, it designed a general framework based on a rule-based decision tree to provide guidance on how reference points could be set and used for diverse types of ecosystem indicators. Fourth, it proposed candidate ecoregions within the Atlantic and Indian Oceans which could be used to guide region-based ecosystem plans, assessments and research to ultimately provide better ecosystem-based advice to inform fisheries management. Fifth, it developed two pilot ecosystem plans for two case study regions, the tropical ecoregion within the ICCAT convention area, and the temperate ecoregion within the IOTC convention area. At this stage, these pilot ecosystem plans aim to create awareness about the need for ecosystem planning, start a discussion about the elements that need to be part of a planning process, and initiate a discussion in ICCAT and IOTC about the potential needs of ecosystem plans and their function. Finally, this project provided recommendations to foster the potential development, use, and implementation of ecosystem plans in ICCAT and IOTC

Trophic structure and fishing impacts on an oligotrophic ecosystem in the Western Mediterranean: the Balearic Islands

Within the context of the ecosystem approach to fisheries management, an ecosystem model was developed for the Balearic Islands in the early 2000s, covering from 0 to 800 m of depth. The aim of the study was to describe the structure and functioning of the ecosystem together with the fishing impacts. The results show that the biomass of the primary producers (PP), mainly dominated by Posidonia oceanica meadows and red algae beds, represented a high percentage of the biomass (39.20%) in the ecosystem. Most of the trophic flows occurred between PP (mostly benthic) and trophic level II. The mixed trophic impact analysis also highlighted a positive impact of the functional groups (FGs) at the base of the food web. Besides, there were important trophic flows between several demersal FGs, and many groups of the pelagic compartment, confirming the importance of the benthopelagic coupling previously reported. The mean trophic level of the catch (mTLc=2.76) was lower than those reported in adjacent areas due to the discard of benthic producers. By excluding benthic PP, the Balearic Islands showed the highest mTLc (3.44) among all the Mediterranean areas modelled, probably due to differences in the trophic structure, lower fisheries exploitation levels and lower development of the purse seine fleet targeting small pelagic fishes. The mean transfer efficiency (21.80%) was double than the global average (10%), which highlights the oligotrophy of the system, the importance of demersal production which has lower rates of transfer through the food web, and a more efficient use of nutrients in the ecosystem. Sponges, one of the most important groups of benthic invertebrates in the Balearic Archipelago, are known to recycle dissolved organic matter, which is reintroduced into the food web similar to the microbial loop, but the magnitude of this and other processes remains still unknown in this area. The present study is a first step to develop spatio-temporal simulations under different exploitation scenarios and to calculate ecological indicators to assess the state of the marine environment in this region.The authors would like to acknowledge all the people who worked on the scientific surveys and the financial support by the following projects: European Union’s Horizon 2020 Research and Innovation Program, EcoScope, CANAL, DRAGONSAL, DISCARDLESS and IDEADOS. X.C. was supported by the Spanish National Program Juan de la Cierva-Formación (MICINN/AEI/10.13039/501100011033 FJC2020-044367-I) funded by the Government of Spain (Ministry of Science and Innovation (MICINN) and the State Research Agency (AEI)) and the European Union (NextGenerationEU/PRTR).Peer reviewe

Economic trade-offs of harvesting the ocean twilight zone: An ecosystem services approach

The mesopelagic or ocean twilight zone (OTZ) in the ocean contains huge numbers of fish in a relatively pristine environment and may therefore attract interest as a commercial fishery. In this study we evaluate in economic terms, the likely trade-offs between the different services provided by the mesopelagic layer in the Bay of Biscay and the societal benefits of its commercial exploitation. Benefits arise mainly from the likely use of this group of species as raw material for producing fishmeal and fish oil. Costs are derived from the loss in climate regulating and cultural, services, but also from the loss in the provisioning service of other commercial species. To do so we compare the current non-exploited status with a situation in where mesopelagic fishes are harvested at levels capable of producing the Maximum Sustainable Yield. Results suggest that if mesopelagic fishes are harvested, a mean value of 1.2 million Euro loss in a year will be created in the Bay of Biscay, although in a range between 42 million Euro loss and 48 Euro million benefits. This uncertainty comes, mainly, from the limited existing knowledge of the mesopelagic fishes’ biomass but also from the uncertainty on the biomass of the rest of the species of the studied ecosystem. The large range indicates that a better understanding of the mesopelagic ecosystem is needed, however, results also show that ecosystem services under no exploitation provided by the OTZ could be more valuable than the fishmeal and fish oil that potentially could be obtained from the fishes harvested in this sea layer

Using ecological models to assess ecosystem status in support of the European Marine Strategy Framework Directive

© 2015 The Authors. Published by Elsevier Ltd. The European Union's Marine Strategy Framework Directive (MSFD) seeks to achieve, for all European seas, "Good Environmental Status" (GEnS), by 2020. Ecological models are currently one of the strongest approaches used to predicting and understanding the consequences of anthropogenic and climate-driven changes in the natural environment. We assess the most commonly used capabilities of the modelling community to provide information about indicators outlined in the MSFD, particularly on biodiversity, food webs, non-indigenous species and seafloor integrity descriptors. We built a catalogue of models and their derived indicators to assess which models were able to demonstrate: (1) the linkages between indicators and ecosystem structure and function and (2) the impact of pressures on ecosystem state through indicators. Our survey identified 44 ecological models being implemented in Europe, with a high prevalence of those that focus on links between hydrodynamics and biogeochemistry, followed by end-to-end, species distribution/habitat suitability, bio-opt ical (remote sensing) and multispecies models. Approximately 200 indicators could be derived from these models, the majority of which were biomass and physical/hydrological/chemical indicators. Biodiversity and food webs descriptors, with ∼49% and ∼43% respectively, were better addressed in the reviewed modelling approaches than the non-indigenous species (0.3%) and sea floor integrity (∼8%) descriptors. Out of 12 criteria and 21 MSFD indicators relevant to the abovementioned descriptors, currently only three indicators were not addressed by the 44 models reviewed. Modelling approaches showed also the potential to inform on the complex, integrative ecosystem dimensions while addressing ecosystem fundamental properties, such as interactions between structural components and ecosystems services provided, despite the fact that they are not part of the MSFD indicators set. The cataloguing of models and their derived indicators presented in this study, aim at helping the planning and integration of policies like the MSFD which require the assessment of all European Seas in relation to their ecosystem status and pressures associated and the establishment of environmental targets (through the use of indicators) to achieve GEnS by 2020