Status of marine fish stocks (CSI 032) - Assessment published Nov 2005

Indicator definition

The indicator tracks the ratio of the number of over-fished stocks to the total number of commercial stocks per fishing area in European seas.
Fish species rarely reproduce randomly with con-species throughout their geographical range, but form a series of stocks that are reproductively isolated in space and time. Cod for instance form a stock in the North Sea and another one in the Iceland area. These are isolated from each other and one can potentially be fished out while the other is thriving. European eel is an example of an extreme situation where there is only one stock as all mature eel migrate to the Sargasso Sea to spawn in random mixture with each other. 

It should be noted that in the Northeast Atlantic area stocks are generally defined based on biological criteria and knowledge of population migration, mixing and spawning areas, while in the Mediterranean due to lack of biological knowledge, stocks are defined largely by area and not in general on the basis of well established biological knowledge on population units.

 

Commercial stocks are the stocks of economic importance on which the fishing effort is focused upon in each area aiming at a profit, i.e. a subset of exploited stocks. It is a broader term encompassing target species, by-catches and industrial species that are of economic importance to the market.
Overfished stocks are stocks outside safe biological limits
Safe stocks are stocks inside safe biological limits
Non-assessed stocks are stocks for which no assessment has been carried out.

The indicator also contains information on:
1. Numbers of commercial, assessed and over-fished stocks by sea area;
2. The state of commercial stocks (over-fished stocks per area), safe stocks, stocks for which an assessment has not been carried out.
3. Fish catch in specific seas from assessed and unassessed stocks.
4. Status of stocks by species and seas.

Units

Landings and spawning stock biomass are given in thousand tonnes, recruitment in million tonnes; fishing mortality is expressed as the proportion of a stock that is removed by fishing activities in a year.

Policy context and targets

Context description

The sustainable exploitation of fish stocks is regulated through the EU Common Fishery Policy (OJ C 158 27.06.1980). Regulatory arrangements, identifying harvesting levels  based on the CFP, the precautionary principle and multi-annual fisheries plans, were set through the Cardiff European Council (COM (2000) 803). Total Allowable Catches (TACs) and quotas for the stocks in the NE Atlantic and the Baltic Sea are set annually by the Fisheries Council. In the Mediterranean Sea, where no TACs have been set except for the highly migratory tunas and swordfish, fisheries management is achieved by means of closed areas and seasons to keep fishing effort under control and make exploitation patterns more rational. The General Fisheries Council for the Mediterranean (GFCM) attempts to harmonise the process.

 

The latest Action Plan on Fisheries management as part of the CFP reform was presented to the Fisheries Council in October 2002, and Council Regulation (EC) No 2371/2002 of 20 December 2002 on the conservation and sustainable exploitation of fisheries resources under the Common Fisheries Policy is now in force. A new set of regulations has since been adopted on specific issues.

Targets

Sustainable exploitation of fish stocks is a target of the EU common fishery policy (CFP).

Total Allowable Catches (TACs) and quotas for the individual stocks in the NE Atlantic and the Baltic Sea are set annually by the Fisheries Council. In the Mediterranean Sea, where no TACs have yet been set (except for the highly migratory tunas and swordfish), fisheries management is achieved by means of closed areas and seasons that are designed to keep fishing effort under control and make exploitation patterns more rational.

Related policy documents

• COM (2000) 803
  Application of the precautionary principle and multiannual arrangements for setting TACs.  ( Cardiff European Council identified harvesting levels.)
• COM (2001) 135 final
  The Green Paper on the future Common Fisheries Policy.COM (2001) 135 final
• Convention for the P...st Atlantic. (OSPAR)
  Convention for the Protection of the Marine Environment of the north-east Atlantic. (OSPAR)
• Convention for the Protection of the Marine Environment and the Coastal Region of the Mediterranean
  The Convention for the Protection of the Mediterranean Sea Against Pollution (the Barcelona Convention) was adopted on 16 February 1976 by the Conference of Plenipotentiaries of the Coastal States of the Mediterranean Region for the Protection of the Mediterranean Sea, held in Barcelona.
• Convention on biological diversity.
  Convention on biological diversity.
• Convention on the Protection of the Marine Environment of the Baltic sea area (HELCOM).
  1992 (entered into force on 17 January 2000)
• Council Regulation (EC) No 2371/2002
  Council Regulation (EC) No 2371/2002 of 20 December 2002 on the conservation and sustainable exploitation of fisheries resources under the Common Fisheries Policy (A new set of regulations have also been adopted on specific issues.)
• EU Common Fishery Policy
  OJ C 158 27.06.1980

Methodology

Methodology for indicator calculation

Number of commercial stocks = 12
Number of assessed stocks = overfished +safe = 1+11= 12
Stock are regarded as within safe biological limits if the stocks size with a high probability is high enough to secure average future recruitment (in technical terms if SSB is above Bpa as defined by ICES). The numbers of overfished and safe stocks have been extracted from the relevant sources. Their ratio has been calculated and presented in pie charts per fishing area.

The above data are from ICES Advice 2006 (section 1.5.1.1 supplemented by Icelandic, Faroese and Barents Sea stocks).  The definition used here is the sum of the stocks listed as overfished and within safe biological limits. Shell fish are not included.

Fish species rarely reproduce randomly with con-species throughout their geographical range, but form a series of stocks that are reproductively isolated in space and time. Cod for instance form a stock in the North Sea and another one in the Iceland area. These are isolated from each other and one can potentially be fished out while the other is thriving. European eel is an example of an extreme situation where there is only one stock as all mature eel migrate to the Sargasso Sea to spawn in random mixture with each other. 

 

Methodology for gap filling

In the case of the Mediterranean since yearly assessment focuses only on four species with limited geographical coverage ( or 6 out of the new 27 units ) it was decided to use the old geographical units and include assessments of species that were presented (ad hoc) in the 2001 assessment.

Methodology references

• ICES Advice Further details on the way ICES formulates advice in precautionary terms.
• Fisheries in the Mediterranean Papaconstantinou, C., and Farrugio, H., 2000, 'Fisheries in the Mediterranean', Mediterranean Marine Science, 1/15-18.

Uncertainties

Methodology uncertainty

All international fisheries organisations use almost the same principles to determine the state of the stocks, and ICES has fine-tuned the methodology used. However decisions are based on safety margins usually set at 30 % above safe limits which in turn bears a degree of uncertainty since estimates of fishing mortality (F) and Spawning Stock Biomass (SSB) are themselves uncertain; the decision on the reference points is then a task for managers, not scientists.

Species and spatial coverage for the Mediterranean is limited. No reference points have been defined for the Mediterranean stocks. The detailed stock assessments for the NE Atlantic and Baltic are obtained through ICES. In the Mediterranean, stock assessments are carried out by the General Fisheries Council for the Mediterranean (GFCM) and, in the absence of complete or independent information on fishing intensity or fishing mortality, are based mainly on landings. Stock assessment is thus based mainly on analysis of landing trends, biomass surveys, and analysis of commercial catch per unit effort (CPUE) data. On the Mediterranean supplementary work is being carried out by DG Fisheries, and a number of internationally funded bottom trawl surveys (MEDITS, SAMED).

Shellfish and cephalopodes are not included in this assessment. It cannot be assumed that fish indicators represent the status of these two groups in relation to sustainable fishing, because they are mainly prey for fish species and will therefore often show the opposite stock development of the fish.

Data sets uncertainty

In the Mediterranean, fisheries management is considered to be at an early stage compared with the NE Atlantic. Catch and effort statistics are not considered to be fully reliable and much effort is directed at estimation of corrective factors (Papaconstantinou & Farrugio, 2000).
Unreported landings are still considered to be a major problem.

Rationale uncertainty

Slightly different approaches are being used in the Mediterranean and the NE Atlantic to determine whether a stock is outside safe biological limits.