Fisheries: European commercial fish stocks

Assessment versions

Published (reviewed and quality assured)

• No published assessments

 

Rationale

Justification for indicator selection

MAIN ADVANTAGES OF THE INDICATOR

• Data sets are based on time series that can give a good account of the state of a stock. Stocks outside safe biological limits per area are identified in the yearly ICES and GFCM reports.
• Policy relevance: links to EU Common Fisheries Policy.
• Biodiversity relevance: shows a real risk of biodiversity loss.

Scientific references

• No rationale references available

Indicator definition

Annual change of proportion of commercial fish stocks within safe biological limits (SBL) in European Seas and per fisheries management unit.

Units

landings are expressed in tonnes, stocks are expressed in number of stocks;

 

Policy context and targets

Context description

One of the main goals of the EU Common Fisheries Policy (CFP) is to take conservation measures to prevent fish stocks from being overexploited.

By comparing trends over time in recruitment (R), spawning stock biomass (SSB), landings and fishing mortality (F), a fairly reliable picture of stock development can be derived. In general when mortality exceeds recruitment and growth, a stock can be characterised as being outside safe biological limits.

Relation of the indicator to the focal area

The 'proportion of commercial fish stocks within and outside safe biological limits' is an indication of the extent to which fish stocks have not been sustainably managed, but overexploited.

Whether all stocks should be within safe biological limits is a societal/political choice. For the individual stocks, and for biodiversity, a sustainably managed stock needs to be within safe biological limits.

Targets

No targets have been specified

Related policy documents

No related policy documents have been specified

 

Methodology

Methodology for indicator calculation

With the introduction of the precautionary approach, a stock is considered to be outside 'Safe Biological Limits' (SBL) when the Spawning Stock Biomass (SSB) (the mature part of a stock) is below a biomass precautionary approach reference point (Bpa), or when the Fishing mortality (F) (an expression of the proportion of a stock that is removed by fishing activities in a year) exceeds a fishing mortality precautionary approach reference point (Fpa), or when both conditions exist. This is the approach followed for stocks in the north-east Atlantic and Baltic Sea.

In the Mediterranean, stock assessment is at a relative early stage of development judged by the criteria of North Atlantic fisheries, and the development of reference points is still underway. Stock assessment of the Mediterranean resources is based  mainly on analysis of landing trends, biomass surveys, and the analysis of commercial catch per unit effort (CPUE) data, given the absence of complete or independent information on fishing intensity or fishing mortality, and stocks are assessed in terms of being over fished or not.

More details can be found in the specification sheet for EEA Core Set indicator 032 at http://themes.eea.europa.eu/IMS/IMS/ISpecs/ISpecification20041007132227/full_spec.

Methodology for gap filling

N/A

Methodology references

No methodology references available.

 

Data specifications

EEA data references

• No datasets have been specified here.

External data references

• Mediterranean stock assessments
• Black Sea stock assessments
• North-East Atlantic Ocean and Baltic sea stock assessments

Data sources in latest figures

 

Uncertainties

Methodology uncertainty

No uncertainty has been specified

Data sets uncertainty

No uncertainty has been specified

Rationale uncertainty

MAIN DISADVANTAGES OF THE INDICATOR

• Different approaches are being used in the Mediterranean and the North Atlantic to determine if a stock is outside safe biological limits. No precautionary reference points are defined for the Mediterranean stocks. With the data that are currently available it is difficult to quantify this indicator and hence 'over fished stocks' is used instead.
• Not all commercial species are monitored (in respect to precautionary approach) in norht-east Atlantic and Baltic and in Mediterranean there is limited species and spatial coverage.
• The final decision on the level of exploitation of stocks (e.g. total allowable catches) is a task for managers/politicians and not scientists. Decisions are based on safety margins usually set at 30 % above safe limits which in turn bear a degree of uncertainty since estimates of F and SSB area uncertain themselves.

ANALYSIS OF OPTIONS

This indicator was selected because of its established methodology and inclusion in the EEA's core set of indicators.

Work description

SUGGESTIONS FOR IMPROVEMENT North-east Atlantic The indicator requires information on SSB, Bpa, F and Fpa. For most stocks that are assessed by ICES this information is available but for others not. If the definition of 'within safe biological limits' is going to be based on these parameters then it should become mandatory that this information becomes available as part of the assessment process. Mediterranean With the data that are currently available it is difficult to fully quantify this indicator at a level similar to the assessment in the norht‑east Atlantic. Therefore the recommendation is that these data should become available for the Mediterranean too. There is currently work in progress to harmonise the ICES and GFCM approaches.

Resource needs

No resource needs have been specified

Status

Not started

Deadline

2099/01/01 00:00:00 GMT+1