Assessing the state of pelagic fish communities within an ecosystem approach and the European Marine Strategy Framework Directive (original) (raw)

Indicators of the health of the North Sea fish community: identifying reference levels for an ecosystem approach to management

ICES Journal of Marine Science, 2006

The shift in emphasis away from the single-species focus of traditional fisheries management towards an ecosystem approach to management requires application of indicators of ecosystem state. Further, an ecosystem approach to management requires the identification of ecological reference points against which management objectives might be set. In applying indicators, identifying reference points, and setting objectives, an obvious requirement is that the indicators respond primarily to the anthropogenic activity being managed and are sufficiently sensitive that impacts of the activity and the responses to management action are clearly demonstrable. Here we apply a suite of 12 indicators to Scottish August groundfish survey data collected in the northern North Sea over the period 1925–1997. These include indicators of size structure, life-history character composition, species diversity, and trophic structure within the community. Our choice of analytical design has two purposes; fir...

Status of pelagic habitats within the EU-Marine Strategy Framework Directive: Proposals for improving consistency and representativeness of the assessment

Marine Policy

Anthropogenic activities have transformed the pelagic habitat in the last decades with profound implications for its essential functions. While the EU-Marine Strategy Framework Directive 2008/56/EC and the Commission Decision (EU) 2017/848 have set criteria and methodological standards for the assessment and determination of Good Environmental Status (GES) for pelagic habitats in EU waters, there is strong evidence that Member States have not yet harmonized the pelagic GES assessment across EU marine waters. Today, pelagic habitats are assessed by evaluating whether good status is achieved by each of the pelagic indicators, but this approach fails to observe the high variability of the pelagic environment. To this end, GES is not estimated at pelagic habitats scale but only for each individual indicator. This paper synthesises the latest developments on pelagic habitats assessment and identifies the main factors limiting the consistency of the assessment across Member States: i) coarse spatial and temporal scales of sampling effort as regards to the pelagic habitat dynamics, ii) little consideration of the whole range of plankton (and, to some extent, of zooplankton) size and trophic spectra, iii) lack of integrated hydro-biogeochemical and biological studies and collaboration among experts from different scientific fields, iv) limited availability of pressure-based indicators, and v) lack of integration methods of the pelagic indicators' status for the GES determination. This analysis demonstrates the importance of maintaining a consistent sampling frequency and a spatially extensive network of stations across the gradient of anthropogenic pressures, where spatial environmental data can help objectively extrapolating field data.

Fishing impact and environmental status in European seas: a diagnosis from stock assessments and ecosystem indicators

Fish and Fisheries, 2014

Stock-based and ecosystem-based indicators are used to provide a new diagnosis of the fishing 34 impact and environmental status of European seas. In the seven European marine ecosystems 35 covering the Baltic and the North-eastern Atlantic: i) trends in landings since 1950 were examined; 36 ii) syntheses of the status and trends in fish stocks were consolidated at the ecosystem level; and iii) 37 trends in ecosystem indicators based on landings and surveys were analysed. We show that yields 38 began to decrease everywhere (except in the Baltic) from the mid-1970s, as a result of the 39 overexploitation of some major stocks. Fishermen adapted by increasing fishing effort and 40 exploiting a wider part of the ecosystems. This was insufficient to compensate for the decrease in 41 abundance of many stocks, and total landings have halved over the last 30 years. The highest 42 fishing impact took place in the late 1990s, with a clear decrease in stock-based and ecosystem 43 indicators. In particular, trophic-based indicators exhibited a continuous decreasing trend in almost 44 all ecosystems. Over the past decade, a decrease in fishing pressure has been observed, the mean 45 fishing mortality rate of assessed stocks being almost halved in all the considered ecosystems, but 46 no clear recovery in the biomass and ecosystem indicators is yet apparent. In addition, the mean 47 recruitment index was shown to decrease by around 50% in all ecosystems (except the Baltic). We 48 conclude that building this kind of diagnosis is a key step on the path to implementing an ecosystem 49 approach to fisheries management. 50 51 Keywords: Ecosystem approach to fisheries management (EAFM), ecosystem indicators, trophic 52 level, good environmental status, Marine strategy framework directive (MSFD), stock assessment 53 54

Evaluation of marine subareas of Europe using life history parameters and trophic levels of selected fish populations

Marine environmental research, 2015

European marine waters include four regional seas that provide valuable ecosystem services to humans, including fish and other seafood. However, these marine environments are threatened by pressures from multiple anthropogenic activities and climate change. The European Marine Strategy Framework Directive (MSFD) was adopted in 2008 to achieve good environmental status (GEnS) in European Seas by year 2020, using an Ecosystem Approach. GEnS is to be assessed using 11 descriptors and up to 56 indicators. In the present analysis two descriptors namely "commercially exploited fish and shellfish populations" and "food webs" were used to evaluate the status of subareas of FAO 27 area. Data on life history parameters, trophic levels and fisheries related data of cod, haddock, saithe, herring, plaice, whiting, hake and sprat were obtained from the FishBase online database and advisory reports of International Council for the Exploration of the Sea (ICES). Subareas inhabit...

Application of Ecological Indicators of the North Sea for Integrated Assessment

2000

Over the past few decades, various indicator sets have been developed in the Netherlands to measure North Sea 'ecological quality', to evaluate the effectiveness of North Sea nature and water policies, and to assist in the communication of predicted ecological impacts of major infrastructural works and other proposed developments in the North Sea. This research study focused on the development

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

Ecological Indicators, 2015

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-optical (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.

Development of the large fish indicator and associated target for a Northeast Atlantic fish community

ICES Journal of Marine Science, 2014

The large fish indicator (LFI) was developed to support the North Sea fish community Ecological Quality Objective (EcoQO) pilot study, intended to establish an operational ecosystem approach to management. Subsequently, procedures established in the North Sea were applied to the Celtic Sea to derive an LFI and target specific to this region. The Marine Strategy Framework Directive (MSFD) requires EU Member States sharing marine regions to cooperate using the Regional Seas Conventions, and using indicators already adopted by them. The MSFD explicitly suggests the LFI as a foodweb indicator, but it could equally well be used to monitor biodiversity. Here, we apply the established rationale to develop an LFI and target specific to the southern Bay of Biscay. Despite declining in the 1990s, the LFI subsequently recovered to near original values in 2008. Previously, relationships between the LFI and fishing pressure have involved lengthy time-lags. We observe a similar relationship, but ...

Monitoring small pelagic fish in the Bay of Biscay ecosystem, using indicators from an integrated survey

This paper is a practical contribution to two important debates raised by the implementation of marine ecosystem based management: (i) which ecosystem data can be provided by a fisheries survey optimised for ecosystem monitoring; and (ii) how to combine/select potential indicators to derive useful information on marine ecosystem status and dynamics? A suite of 143 potential indicators, including spatial indices, representing small pelagic fish and their biotic and abiotic environments are presented. Indicators were routinely derived from the PELGAS integrated ecosystem survey conducted in spring in the Bay of Biscay (BoB). The general patterns over time in this suite of 5-16 years, non-stationary time series are characterised using a methodology based on min-max autocorrelation factors (MAF), to select the most continuous indicators within, and across, several ecosystem components: hydrology, phytoplankton, mesozooplankton, small pelagic fish and megafauna. Potential interactions between selected indicators and external forcing variables, including climate and fishing, were assessed. The results confirm the importance of river discharges, bottom temperature, chlorophyll-a and mesozooplankton biomass in the dynamics of the BoB pelagic ecosystem. Small pelagic fish species appear to have followed distinct trajectories during the last 15 years. A marked decrease in anchovy and sardine mean weights at ages 1 and 2 over the last 15 years was highlighted; potentially caused by density-dependent competition. The quasi-absence of significant correlation between selected survey indicators and climate and fishing pressure proxies suggests a moderate exploitation rate of small pelagic fish resources, and confirms the so far limited effects of large-scale climate forcing on the BoB pelagic ecosystem. Perspectives for the assessment of marine ecosystem status on the basis of suites of indicators derived from integrated ecosystem surveys are discussed.