On the 9th June 2006 the ICES’ Advisory Committee on Fishery Management (ACFM) published their advice to the European Commission on the two Baltic Sea cod stocks for 2007. The following provides a summary and comment on their assessments and advice.
Baltic Sea cod in subdivisions 22-24 (Western Baltic)
- The quantity of mature cod (also known as the spawning stock biomass or “SSB”) within this cod stock is estimated to be approximately 23,000 tonnes.
- Coincidentally, 23,000 tonnes of mature fish is considered to be the precautionary minimum level that will allow the cod stock to sustain itself. The use of a precautionary level takes account for the uncertainties involved in calculating the SSB.
- Fishing has altered the age and subsequently the size structure of the cod stock to the point that many of the older, larger fish have been removed. This means that the stock is highly dependent upon those fish that reach maturity each year.
- Over the last 7 years there have been relatively low numbers of cod reaching maturity. This is thought to be primarily caused by unfavorable environmental conditions and continual high levels of fishing on the mature stock.
- The amount of fish that are killed by fishing (known as fishing mortality or “F”) is considered to be too high. In 2006, the fishing mortality of cod was estimated to be 1.26. This implies that 1.26 times as many cod were caught as were present at the beginning of the year. A fishing mortality above 1 is possible as fish mature and grow to a size where they join or “recruit” to the fishery throughout the year and are subsequently killed by fishing. However, if only low numbers of cod are reaching maturity and recruiting to the fishery, a high fishing mortality results in the stock being harvested unsustainably.
- The stock is categorised as being “over exploited” with respect to the potential long-term yield, i.e., more fish could be taken from the stock in the future if fishing mortality was reduced.
- ICES have previously recommended fishing mortalities of 0.3 – 0.6, to ensure that the stock would sustain itself and provide long term yields.
- Taking into account the low numbers of cod that are reaching maturity and by also applying precautionary limits that take account of the uncertainty in stock assessments, ICES have advised that the total allowable catch (TAC) for 2007 should not exceed 20,500 tonnes. The recommended TAC for 2006 was 28,400 tonnes and was accepted by the European Fisheries Council.
Baltic Sea cod subdivisions 25-32 (Eastern Baltic)
- The SSB is estimated to be below 100,000 tonnes.
- ICES estimate that a SSB of 160,000 tonnes is a level below which there is a high risk that the numbers of mature fish will seriously decline and the stock could collapse.
- The stock is at historically low levels and there is no indication of an increase in the SSB.
- Evidence suggests that for this stock low recruitment coincides with low SSB.
- The estimated fishing mortality is considered to be too high. In 2006 it was estimated to be 1.11. It is described as being “over exploited” with respect to the potential long-term yield for the fishery and being “harvested unsustainably”.
- ICES have previously recommended a target fishing mortality of 0.3.
- Indications are that the 2003 year-class (those fish that were spawned or hatched in 2003) have survived well compared to the previous 15 year-classes.
- Baltic Sea cod mature and recruit to fishery when they are 3-5 years old. This means the 2003 year-class has the potential to make a good contribution to the fishery and, if not over exploited, to increasing the SSB.
- For some years misreporting has been a major problem in this fishery. ICES estimate that recent catches have been 35-45% higher than reported figures and have chosen to include these estimates in their assessment.
- The cumulative effective of inaccurate catch data and the use of estimated catches mean that there are large uncertainties in the assessment for all year classes.
- ICES recommend that there should be no catch from this stock in 2007 and a recovery plan should be developed and implemented as a prerequisite to reopening the fishery. The recommended TAC for 2006 was 14,900 tonnes, however, the European Fisheries Council set the TAC at 49,220 tonnes.
The European Commission, after consulting with their advisory Scientific, Technical and Economic Committee for Fisheries (STECF), will publish their recommendations to Fisheries Council prior to the Council’s October meeting, where the 2007 TAC and quotas will be agreed. In the meantime, the European Commission on behalf of the EU, will negotiate with Russia, who also fish for cod in the eastern Baltic, an acceptable cod quota.
Furthermore, in 2007 the European Commission intends to have in place a multi-annual management plan for both stocks. The plan is expected to be published in July 2006 and is likely to focus on a gradual reduction in fishing mortality and fishing effort with the aim of allowing the stocks to reach levels that will provide stable catches in the long term.
The ICES advice was provided in the absence of the plan and so did not take into account any potential management objectives and criteria that such a plan might put in place. Therefore, it seems likely that the outcome of the Council will be reduced TACs, in comparison to 2006, for both cod stocks and reduction in fishing effort in the form of fewer days allowed for fishing and seasonally closed areas.