Report of the Working Group on Eels (WGEEL), 2016: ICES WGEEL REPORT 2016
Research output: Book/Report › Report not published by INBO › Research
|Place of Publication||Copenhagen|
|Publisher||International Council for the Exploration of the Sea (ICES)|
|Volume||ICES CM 2016/ACOM:19|
|Number of pages||107|
|Publication status||Published - Oct-2016|
In 2016, the WGEEL glass eel recruitment indices remain low at 2.7% of the 1960–1979 reference level in the ‘North Sea’ series, and 10.7% in the ‘Elsewhere’ series. The ‘recruiting yellow eel’ index was 21% of the level during the reference period.
The Eel Management Plan silver eel biomass and mortality rate estimates (reported in 2015) indicate the stock in the EU-assessed area is not within the biomass limits of the Eel Regulation and in most management units, anthropogenic mortality exceeds a level that can be expected to lead to recovery.
FAO reports the total landings from Commercial fisheries in 2014 were about 3321 t of eel. Six countries account for 73% of the FAO landings: France, Egypt, UK, Netherlands, Sweden and Denmark. Five EU Member States have a glass eel fishery (France, UK, Spain, Portugal and Italy): some non-EU countries (e.g. Morocco) also have glass eel fisheries but data from these were not available for analysis. The best estimates of the total EU catch of glass eel in 2015 and 2016 were 51.6 and 59.2 t, respectively.
About 10.6 million glass eels and 9.2 million yellow eels were stocked in 2015. Stocking is a component of many Eel Management Plans (EMPs) and in some cases the commitment could not be achieved in 2016 due to timing, market and other glass eel availability issues. Aquaculture production was about 4000–6500 t in 2015/2016 (data from FAO, FEAP and WGEEL Country Reports).
WGEEL attempts to cross-check glass eel catch with records of their fate (consumption, restocking and aquaculture) reveal major discrepancies between reporting systems. About 32% of the catch for 2015 has no recorded fate (about 36% for 2016). EuroStat trade data show France and UK declared exports of glass eel to Hong Kong in 2015/2016 despite these being ‘banned’ by the EU application of CITES.
The EU Eel Regulation effectively implements a Distributed Control System, in which common objectives (protection and recovery, minimal spawner production of 40% relative to the notional pristine production) are achieved by collective action (national management plans, reducing mortalities). Effective governance across the whole stock requires other areas to adopt the same approach of distributed control. Most non-EU areas have only recently joined this process, and further development - of reference points, assessment procedures, and feedback mechanisms - might be required, to cope with unforeseen complications and/or to familiarise local experts, and involve them in future standardisation processes. Additionally, reference points, assessment procedures and feedback mechanisms will need to be agreed for the whole distribution area.
A mechanism needs to found between the EU and the ICES rules to facilitate feedback on the status of the implementation of the EMPs, as in the Eel Management Plan Evaluation workshop (WKEPEMP) in 2013 (ICES, 2013). This lack leaves a void between the formal Precautionary Advice and scientific support for the recovery plan on eel.
Knowledge gaps and research needs were identified regarding impacts of pollutants and hydropower, habitat preferences, and monitoring across environments. A recent review shows that evidence on net benefits of eel stocking is inconclusive. Emerging threats include climate change, pollution and post-release mortalities from recreational fisheries. New opportunities include research on migratory triggers and habitat use, survey methods in large water bodies, protection for eel passing hydropower facilities, and coordinating eel management and data collection in the Mediterranean.
Research output (related by authors)
Research output: Contribution to journal › A1: Web of Science-article › Research › peer-review
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