Status of marine fish and shellfish stocks in European seas

Indicator Specification
Indicator codes: CSI 032 , MAR 007
Created 10 Jun 2019 Published 04 Oct 2019 Last modified 04 Oct 2019
13 min read
The indicator tracks both the status of commercial fish stocks in European regional seas and the pressure exerted by fisheries on those stocks, as well as the quality of the information available. To that end, the following is reported: the status of marine fish and shellfish stocks based on the current level of exploitation and reproductive capacity; the importance of the (sub-)region, reflected by the total landings (as a proxy of catch) of fish from commercial fisheries in European seas per MSFD (sub-)region; the availability of appropriate information for the status assessment, as reflected by the proportion of those landings covered by quantitative stock assessments (i.e. the proportion providing the required indicators and their reference levels). Status of marine fish and shellfish stocks The MSFD requires GES to be achieved by 2020 (EC, 2008). According to the MSFD (Descriptor 3), three criteria are relevant to determining if a fish or shellfish stock has achieved GES:  (1) it should be exploited sustainably, consistent with high long-term yields; (2) it should have full reproductive capacity, to maintain stock biomass; and (3) a certain proportion of older and larger fish/shellfish should be maintained (or increased), as this is an indicator of a healthy stock. Sustainable exploitation: sustainably exploited stocks are stocks for which F is at or below levels that deliver MSY, i.e. F ≤ F MSY . Thus, a stock is considered to have been assessed against this criterion only if values for F and F MSY  are available, and the stock is considered to have achieved GES only if F ≤ F MSY . Reproductive capacity: in areas assessed by the International Council for the Exploration of the Seas (ICES), the criterion for sustainable reproductive capacity (SSB > SSB MSY ) has been changed, for pragmatic reasons, to SSB > MSY B trigger . SSB is consistently provided as part of ICES stock assessments, i.e. of the North-East Atlantic Ocean and Baltic Sea, but not, for the most part, by assessments of the Scientific, Technical and Economic Committee for Fisheries (STECF), i.e. of the Mediterranean and Black Sea stocks. Similarly to the above, a stock is considered to have been assessed against this criterion if values for SSB and a good proxy for SSB MSY  (i.e. MSY B trigger ) are available, and the stock is considered to have achieved GES only if SSB > SSB MSY  (or an appropriate proxy). Healthy age and size structure: in this case, the assumption is that a stock with sufficient numbers of old and large fish is healthy. However, this criterion is not sufficiently developed and no threshold for GES is known for this criterion. Therefore, it is not included. This has resulted in four assessment categories: not assessed: no sufficient information available to assess status; F: status assessed based only on F and F MSY; SSB: status assessed based only on SSB and SSB MSY  (or some proxy, i.e. MSY B trigger ); F and SSB: status assessed based on both F and SSB.   Because of ongoing discussions about the criteria integration rules for descriptor 3, the stocks are classified as: assessed stocks for which adequate information is available to determine GES based on F and SSB; assessed stocks for which insufficient information is available to determine GES based on F or SSB; assessed stocks for which insufficient information is available to determine GES according to both reference points F and SSB.   For those stocks for which adequate information is available to determine GES based on fishing mortality (F) and/or reproductive capacity (SSB), a second distinction is made between (1) stocks in good status based on both fishing mortality and reproductive capacity; (2) stocks in good status based on only one criteria (either because one of the two criteria is in good status or data are available for only one criteria and it is in good status); and (3) stocks not in good status (either because one of the two criteria is not in good status or data are available for only one criteria and it is not in good status). Total landings Landings information for the North-East Atlantic and the Baltic Sea is based on the ICES  official nominal catches, 2006-2017 data set . Fisheries nominal catch statistics are reported annually by national offices. In cooperation with Eurostat and the Food and Agriculture Organization of the United Nations (FAO), the ICES prepares and publishes the official nominal catch statistics data set for the North-East Atlantic (FAO major fishing area 27). Landings information for the Mediterranean Sea and the Black Sea is based on the FAO's capture production data set. For the Mediterranean and Black Seas, the figures are based on 2016 landings data. Only some of the species/taxa in the landings data can be considered 'commercial fish', which, for assessment purposes, may consist of several stocks. Only some of these stocks are covered by quantitative stock assessments such that their status can be assessed based on the above criteria. Stocks In the North-East Atlantic area, stocks are generally defined based on biological criteria and knowledge of population migration, mixing and spawning areas. For example, cod in the North-East Atlantic is currently considered to form 16 different stocks, between which mixing is generally negligible. These stocks are found over multiple MSFD ecoregions, and some individual stock distributions cover more than one ecoregion. However, in this analysis each stock has been assigned to a single ecoregion (see Methodology). In the Mediterranean and Black Seas, on the other hand, stocks are mostly defined by management area because of a lack of biological knowledge. Because these stocks are based on a specific geographical area, most can be attributed to a specific MSFD (sub-)region.

Assessment versions

Published (reviewed and quality assured)

Rationale

Justification for indicator selection

Commercial fish and shellfish provide most of the seafood derived from European waters and, if sustainably exploited, they could be a continuous source of healthy protein. However, the heavy exploitation of fish and shellfish can affect their reproductive capacity and thus their potential for recovery. To achieve sustainability, the levels of exploitation and reproductive capacity need to be analysed to assess the status of marine fish and shellfish in Europe. The fact that only those stocks for which regular quantitative stock assessments are conducted can be included in such a status assessment means that it is important to show what proportion of commercial species is covered by quantitative stock assessments.

Therefore, this indicator consists of three parts:

  • the proportion of the total catch in the MSFD (sub-)regions of Europe covered by the quantitative stock assessments conducted by the ICES and the General Fisheries Commission for the Mediterranean (GFCM);
  • the proportion of the total landings in the MSFD (sub-)regions of Europe covered by quantitative stock assessments conducted by the ICES and the GFCM;
  • an overview of the status of assessed fish stocks per MSFD (sub-)region and its trend over time, with GES being based on two criteria being met:
    • a sustainable level of exploitation (assessed by F);
    • reproductive capacity not being compromised (assessed by SSB).

Scientific references

Indicator definition

The indicator tracks both the status of commercial fish stocks in European regional seas and the pressure exerted by fisheries on those stocks, as well as the quality of the information available. To that end, the following is reported:

  • the status of marine fish and shellfish stocks based on the current level of exploitation and reproductive capacity;
  • the importance of the (sub-)region, reflected by the total landings (as a proxy of catch) of fish from commercial fisheries in European seas per MSFD (sub-)region;
  • the availability of appropriate information for the status assessment, as reflected by the proportion of those landings covered by quantitative stock assessments (i.e. the proportion providing the required indicators and their reference levels).

Status of marine fish and shellfish stocks

The MSFD requires GES to be achieved by 2020 (EC, 2008). According to the MSFD (Descriptor 3), three criteria are relevant to determining if a fish or shellfish stock has achieved GES: (1) it should be exploited sustainably, consistent with high long-term yields; (2) it should have full reproductive capacity, to maintain stock biomass; and (3) a certain proportion of older and larger fish/shellfish should be maintained (or increased), as this is an indicator of a healthy stock.

  • Sustainable exploitation: sustainably exploited stocks are stocks for which F is at or below levels that deliver MSY, i.e. F ≤ FMSY. Thus, a stock is considered to have been assessed against this criterion only if values for F and FMSY are available, and the stock is considered to have achieved GES only if F ≤ FMSY.
  • Reproductive capacity: in areas assessed by the International Council for the Exploration of the Seas (ICES), the criterion for sustainable reproductive capacity (SSB > SSBMSY) has been changed, for pragmatic reasons, to SSB > MSY Btrigger. SSB is consistently provided as part of ICES stock assessments, i.e. of the North-East Atlantic Ocean and Baltic Sea, but not, for the most part, by assessments of the Scientific, Technical and Economic Committee for Fisheries (STECF), i.e. of the Mediterranean and Black Sea stocks. Similarly to the above, a stock is considered to have been assessed against this criterion if values for SSB and a good proxy for SSBMSY (i.e. MSY Btrigger) are available, and the stock is considered to have achieved GES only if SSB > SSBMSY (or an appropriate proxy).
  • Healthy age and size structure: in this case, the assumption is that a stock with sufficient numbers of old and large fish is healthy. However, this criterion is not sufficiently developed and no threshold for GES is known for this criterion. Therefore, it is not included.

This has resulted in four assessment categories:

  • not assessed: no sufficient information available to assess status;
  • F: status assessed based only on F and FMSY;
  • SSB: status assessed based only on SSB and SSBMSY (or some proxy, i.e. MSY Btrigger);
  • F and SSB: status assessed based on both F and SSB.

 

Because of ongoing discussions about the criteria integration rules for descriptor 3, the stocks are classified as:

  • assessed stocks for which adequate information is available to determine GES based on F and SSB;
  • assessed stocks for which insufficient information is available to determine GES based on F or SSB;
  • assessed stocks for which insufficient information is available to determine GES according to both reference points F and SSB.

 

For those stocks for which adequate information is available to determine GES based on fishing mortality (F) and/or reproductive capacity (SSB), a second distinction is made between (1) stocks in good status based on both fishing mortality and reproductive capacity; (2) stocks in good status based on only one criteria (either because one of the two criteria is in good status or data are available for only one criteria and it is in good status); and (3) stocks not in good status (either because one of the two criteria is not in good status or data are available for only one criteria and it is not in good status).

Total landings

Landings information for the North-East Atlantic and the Baltic Sea is based on the ICES official nominal catches, 2006-2017 data set. Fisheries nominal catch statistics are reported annually by national offices. In cooperation with Eurostat and the Food and Agriculture Organization of the United Nations (FAO), the ICES prepares and publishes the official nominal catch statistics data set for the North-East Atlantic (FAO major fishing area 27). Landings information for the Mediterranean Sea and the Black Sea is based on the FAO's capture production data set. For the Mediterranean and Black Seas, the figures are based on 2016 landings data.

Only some of the species/taxa in the landings data can be considered 'commercial fish', which, for assessment purposes, may consist of several stocks. Only some of these stocks are covered by quantitative stock assessments such that their status can be assessed based on the above criteria.

Stocks

In the North-East Atlantic area, stocks are generally defined based on biological criteria and knowledge of population migration, mixing and spawning areas. For example, cod in the North-East Atlantic is currently considered to form 16 different stocks, between which mixing is generally negligible. These stocks are found over multiple MSFD ecoregions, and some individual stock distributions cover more than one ecoregion. However, in this analysis each stock has been assigned to a single ecoregion (see Methodology).

In the Mediterranean and Black Seas, on the other hand, stocks are mostly defined by management area because of a lack of biological knowledge. Because these stocks are based on a specific geographical area, most can be attributed to a specific MSFD (sub-)region.

Units

The units used in this indicator are tonnes, as well as the proportion of catch for assessed stocks/non-assessed stocks. The assessment information is expressed as the proportion of landings covered by assessed stocks. The status of the assessed stocks can be expressed as the proportion of the landings of assessed fish and shellfish stocks or the proportion or number of fish and shellfish stocks.

Policy context and targets

Context description

The scope of the CFP includes the conservation of marine biological resources and the management of the fisheries that target them. To that end, the CFP should adapt exploitation rates to ensure that, within a reasonable time frame, the exploitation of marine biological resources allows the restoration and maintenance of populations of harvested stocks above levels that can produce the MSY. This should have been achieved by 2015 or should be achieved no later than 2020.

The aim of the MSFD is to achieve GES of the EU's marine waters by 2020 and to protect this resource, upon which marine-related economic and social activities depend. The MSFD enshrines in a legislative framework the ecosystem approach to the management of human activities that have an impact on the marine environment, integrating the concepts of environmental protection and sustainable use.

To achieve its goal, the directive establishes European marine regions and sub-regions on the basis of geographical and environmental criteria. The MSFD significantly strengthens Member States’ competences and responsibilities to maintain or achieve GES for all exploited fish and shellfish stocks inside territorial waters and exclusive economic zones (EEZs) with common goals. Three criteria in relation to GES have been identified for commercial fish and shellfish:

  • the level of exploitation;
  • reproductive capacity;
  • age and size distribution.

These requirements for GES, according to the MSFD, are aligned with the requirement for MSY for both the 'level of exploitation' and 'reproductive capacity' criteria. The 'age and size distribution' criterion is not yet sufficiently developed.

Targets

The MSFD aims to ensure that:

  • populations of all commercially exploited fish and shellfish are within safe biological limits, exhibiting a population age and size distribution that is indicative of a healthy stock being produced no later than 2020 (EC, 2008, Annex I);
  • all EU fish and shellfish stocks should be fished to produce an MSY no later than 2015 (EC, 2006); this implies that the targets are to achieve F ≤ FMSY and SSB ≥ SSBMSY (MSY Btrigger is used as a best proxy for SSBMSY).

Related policy documents

Key policy question

How far is Europe from achieving a robust assessment of the Marine Strategy Framework Directive's 'good environmental status' for commercial fish and shellfish stocks?

Methodology

Methodology for indicator calculation

North-East Atlantic Ocean and Baltic Sea

For the North-East Atlantic Ocean (considering the sub-regions) and Baltic Sea, this indicator is calculated using the ICES stock assessment database. The ICES stock assessment database consists of 155 stock assessments, and provides information, by stock and by year, on a number of variables. The period for which this information is available varies depending on the stock.

Proportion of assessed stocks

Initially, two criteria are used to determine the status of commercial fish stocks, with GES being based on these criteria being met:

  • sustainable exploitation, consistent with high long-term yields;
  • full reproductive capacity.

F and SSB, in combination with an MSY-based reference value, are the most appropriate metrics for these two criteria. The metrics used for F and SSB may differ between stocks. It is preferable for F to be expressed as fishing pressure and SSB as stock size. This may result in a different number of stocks being assessed for each metric. 

Total landings in MSFD (sub-)regions

Stocks are assigned to an MSFD ecoregion based on the ICES sub-areas and -divisions mentioned in the Stocks sub-section of the indicator description. Please note that the MSFD regions assigned to fish stocks are not conclusive and may change after further consultation. The ICES is also presently developing a system for assigning stocks to appropriate ecoregions based on distribution and migration patterns as well as the location of landings. As landings are assigned to stock level rather than ecoregion level, landings may need to be redistributed over the different ecoregions. The ICES official nominal catches data set is used to calculate proportions, to redistribute stock landings over the different ecoregions. Landings are selected for species and areas as described in the stock description for stocks that cover more than one ecoregion. Selected landings are assigned to MSFD ecoregion. Thereafter, the proportion of landings in each ecoregion, in relation to the total selected landings, is calculated. The total landings by ecoregion are used to calculate the proportion, to redistribute stock landings over ecoregions.

Total landings data are extracted from the ICES official nominal catches data set (note: in FAO terminology, ‘nominal catches’ refer to ‘landings’) and are assigned to the different MSFD sub-regions based on area. The total landings for non-assessed stocks by ecoregion are calculated by subtracting total stock landings by ecoregion from the total landings by ecoregion.

Good status

The status of commercial species per MSFD ecoregion is assessed based on all stocks for which the required information on F and/or SSB is available. For each region, the proportion of stocks that fulfil one (only F or only SSB if both criteria are known), both (F and SSB) or neither (F nor SSB if only a single criterion is known) of the MSFD criteria for GES is calculated. Thus, the five different categories are:

  • F only: stocks for which information on only F is available and that fulfil the MSFD criterion for GES based on F;
  • SSB only: stocks for which information on only SSB is available and that fulfil the MSFD criterion for GES based on SSB;
  • F and SSB: stocks for which information on F and SSB is available and that fulfil the MSFD criteria for GES based on F and GES based on SSB;
  • F or SSB: stocks for which information on F and SSB is available and that fulfil the MSFD criterion for GES based on F or GES based on SSB;
  • none: stocks for which information on F and SSB is available and that do not fulfil the MSFD criterion for either of the two; or stocks for which information on only F or on only SSB is available and that do not fulfil the GES criterion.


Mediterranean and Black Seas

Proportion of assessed stocks

For the Mediterranean and Black Seas, information on assessed stocks is extracted from STECF Mediterranean and Black Sea Working Group reports. As assessments are carried out in a multiannual cycle, different stocks are included in each yearly working group report. Generally, stocks cover one or several geographical sub-areas (GSAs).

Initially, two criteria are used to determine the status of commercial fish stocks, with GES being based on these criteria being met:

  • sustainable exploitation, consistent with high long-term yields;
  • full reproductive capacity.

F and SSB, in combination with an MSY-based reference value, are the most appropriate metrics for these two criteria. The metrics used for F and SSB may differ between stocks. It is preferable for F to be expressed as fishing pressure and SSB as stock size. This may result in a different number of stocks being assessed for each metric. 

Total landings in MSFD (sub-)regions

Landings information for the Mediterranean and Black Seas is extracted from the FAO regional workspace including on 'GFCM (Mediterranean and Black Sea) capture production'. Landings information is available by fishing area (FAO division). Total landings for the assessed stocks for the Mediterranean and Black Seas are calculated by selecting landings for the species for which STECF provides F/FMSY information, where the following assumptions are made:

  • As the multiple fishing areas of the Mediterranean Sea do not directly coincide with the GSAs, overall landings are used for the Mediterranean Sea for the assessed species.
  • Landings are extracted by linking the common name in the stock description with the species name in the landings data set.

The total landings for non-assessed stocks in the Mediterranean and Black Seas are calculated by subtracting the total landings calculated for assessed stocks from the total landings for these two regions. 

Good status

Assessed as for the North-East Atlantic Ocean and Baltic Sea.

Methodology for gap filling

Not applicable

Methodology references

Data specifications

EEA data references

  • No datasets have been specified here.

External data references

Data sources in latest figures

Uncertainties

Methodology uncertainty

MSFD (sub-)regions

The matching of catch areas and stocks to the MSFD regions/sub-regions is not final and may change following further consultations.

Data sets uncertainty

Catch and stock assessment data

Depending on the year selected, the suite of assessed stocks may change (in the Mediterranean and Black Seas because they do not conduct annual stock assessments for all stocks simultaneously; and in the ICES areas because many stocks are assessed only every 2 or 3 years). This may lead to indicator values changing simply because different stocks are considered each year.  Therefore, the analyses presented here use the results of the latest assessment for each stock from the last 3 years (under the assumption that the most recent assessment is indicative of status until the next assessment is conducted).

Rationale uncertainty

Status of commercial species

The status of commercial species is expressed as the proportion of stocks that fulfils one or more of the GES criteria, as this is the most straightforward method, since it does not require any additional information. However, status can also be expressed as a proportion of catches or a proportion of biomass, depending on data availability. Each method is likely to give different results. The pros and cons of each method should be considered and a best method should be agreed upon.

Similarly, the status of European marine fish and shellfish over time is shown for both GES criteria considered as the annual mean ratio indicator/GES threshold, while, alternatively, the annual mean ratio deviation of the indicator from the GES threshold relative to that threshold can be calculated. This is also likely to give different values, but is unlikely to give rise to different conclusions. The pros and cons of each method should be considered and a best method should be agreed upon.

For compliance with the status assessments in relation to the CFP, the same stocks for the Mediterranean Sea as those used by the STECF are adopted. This implies that, in contrast with the previous assessment, only stocks assessed by the GFCM (hence not the International Commission for the Conservation of Atlantic Tunas (ICCAT)) are used for this assessment.

Further work

Short term work

Work specified here requires to be completed within 1 year from now.

Long term work

Work specified here will require more than 1 year (from now) to be completed.

General metadata

Responsibility and ownership

EEA Contact Info

Ana Tejedor

Ownership

European Environment Agency (EEA)

Identification

Indicator code
CSI 032
MAR 007
Specification
Version id: 4

Frequency of updates

Updates are scheduled once per year

Classification

DPSIR: State
Typology: Descriptive indicator (Type A - What is happening to the environment and to humans?)

Related content

Data references used

Latest figures and vizualizations

Relevant policy documents

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