Accelerating the recovery of the European Eel



Executive Summary. A Workshop on Designing an Eel Data Call (WKEELDATA), (chaired by: Caroline Durif, Norway), met in Rennes, France, from 28 February to 2 March 2017 to plan a data call that is to be sent to all countries having natural production of European eel.

The workshop follows a need to standardize data reporting, increase its coverage, and improve data quality. A data call will ensure a more consistent and systematic approach to data reporting.

European eel life cycle is complex with a unique spawning area in the Sargasso Sea but growth areas widely distributed across Europe. The stock is genetically panmictic but the continental eel stock shows strong local and regional differences in population dynamics and local stock structures (sex ratio, length and age distributions). Data are reported to the Working Group on Eel (WGEEL), which generates the advice. Data correspond to several different life stages, from juveniles to prespawning eels, caught with various fishing gears in different habitats (from freshwater to saltwater environments). Local impacts by fisheries may vary from almost nil to heavy overexploitation. Other forms of anthropogenic mortality (e.g. hydropower, pumping stations) also impact on eel and vary in distribution and local relevance.

Most, but not all EU Member States reported quantitative estimates of the required stock indicators to the EU in 2012, and 2015. The reliability and accuracy of these data have not yet been fully evaluated, but WGEEL has identified weaknesses during its annual meetings. One of the main shortcomings is the lack of stock indicators in some non-European countries within the natural range of the European eel.

ICES started to launch official calls for fisheries-dependent data in 2012. Since then, data calls have been an integrated element in the process of addressing recurring advice requests as well as special requests.

The terms of reference were addressed by reviewing the data requirements and defining data quality standards. The WKEELDATA group reviewed the spreadsheets that are requested to be filled in by each country assessor. The types of data were rated according to how well they responded to the requests of WGEEL. At present, recruitment time-series of eels recruiting to continental habitats are the only data that are organized into a database. WKEELDATA participants agreed that expanding this database was the most efficient and sustainable manner to organise data from WGEEL. Notable progress was made during and after the workshop towards this aim. The WKEELDATA participants developed a 2-year plan to carry this out in a reasonable and realistic manner. New spreadsheets were created to facilitate data entry. These spreadsheets which follow the structure of the database, are included in the data call along with the main text. The main text for the data call was drafted during the workshop and finalized the months following the workshop.

DOWNLOAD Executive Summary