Scottish Government

Indicators of Sustainable Development for Scotland

Indicator 11. Sea fisheries

Proportion of fish stocks which are within safe biological limits

Source: Fisheries Research Services and ICES

Note: The 21 monitored fishstocks are: North Sea Cod, West of Scotland Cod, North Sea Haddock, West of Scotland Haddock, Rockall Haddock, North Sea Whiting, West of Scotland Whiting, Saithe - VI + IV + IIIa, Northern Hake, North Sea Anglerfish, West of Scotland Anglerfish, North Sea Herring, Western Mackerel, North Sea Mackerel, North Sea Norway Pout, North Sea Sandeel, Northern Blue Whiting, Blue ling Sub-area VI, Tusk Sub-area VI, Roundnose grenadier Sub-area VI, Black scabbard fish Sub-area VI and Orange roughy Sub-area VI.

The relevance of the indicator

We need to live within the capacity of the planet to sustain our activities and replenish resources which we use. Sea fisheries is a key area where this applies.

Choice of Indicator

Many marine fish stocks have been monitored over a long time period and therefore good quantitative data are available. The indicator used is a standard measure used by the International Council for the Exploration of the Sea (ICES) to classify the state of exploited fish stocks.

Detailed definition and source details

'Safe biological limits' are defined by a minimum safe stock size and a maximum exploitation rate. These are known as reference points. The stock size is measured in terms of 'spawning stock biomass (SSB)' which represents the total weight of spawning fish each year. The exploitation rate is called the 'fishing mortality (F)' which measures the rate at which fish are removed from the stock by fishing. If the stock is either below the minimum safe SSB or above the maximum safe F, the stock is said to be outside safe biological limits.

The definitions of the reference points are given by the Advisory Committee for Fishery Management (ACFM). This is an ICES committee and copies of the relevant reports can be found on the ICES website ²⁵.

Trends

The available data suggest that the number of stocks outside safe biological limits is increasing, implying a gradual worsening of the indicator.

Further disaggregation

The four stocks currently within safe biological limits in Scottish waters are Norway Pout, Sandeel, North Sea Herring and Saithe. Some of those stocks which are outside safe biological limits, such as Cod, Haddock, Plaice and Whiting for example, are particularly at risk (ie close to collapse). No further disaggregation of the information held is possible.

Target

No current target - but our ambition is to ensure that all major species in Scottish waters are within safe biological limits.

Action

Formally, competence in the management of stocks beyond 6 miles of the coast lies with the European Union. For many important Scottish stocks in the North Sea, management responsibility is shared between EU and Norway.

The recent review of the Common Fisheries Policy agreed several important measures to increase sustainability of stocks, including effort limitations on directed fishing for stocks outside safe biological limits and multi-annual management plans for all stocks. Scottish Executive remains fully involved in a continuing review which includes consideration measures designed to reduce discarding of undersized fish and the integration of broad environmental protection measures into the Common Fisheries Policy.

We work closely with DEFRA and the scientific community to influence Commission and Council fisheries policy.

We also take unilateral action to improve things for stocks where Scotland takes the largest share. Alone in the EU, Scotland has banned the use of strengthening bags and places autonomous restrictions on multiple rig trawling. We were the first country in Europe to introduce mandatory 90mm square mesh panels.