REPORT OF THE JOINT EIFAAC/ICES/GFCM WORKING GROUP ON EELS (WGEEL)

The Joint EIFAAC/ICES/GFCM Working group on eels (WGEEL) met in a split meeting from 4–8 September (online) and 25 September–02 October 2023 (hybrid meeting) in Helsinki, Finland, to provide the scientific basis for the ICES advice on fishing opportunities and conservation as-pects for the European eel and address requests from EIFAAC and GFCM. WGEEL assessed the state of the European eel and its fisheries, collated and analysed biometric data, reviewed the implementation of the WKFEA (Workshop on the future of eel advice) roadmap, examined available recruitment data from coastal and marine habitats, reported on any updates to the scientific basis of the advice, new and emerging threats or opportunities, in-cluding developments in the Mediterranean region. After high levels in the late 1970s, the recruitment declined dramatically in the 1980s and remains low. Compared to 1960–1979, the recruitment in the “North Sea” was 0.4% in 2023 (provisional) and 0.7 % in 2022 (final). In the “Elsewhere Europe” index series was 8.8 % in 2023 (provisional) and 11.3% in 2022 (final). For the yellow eel data series, recruitment for 2022 was 9% (final). Time-series from 1980 to 2023 show that glass eel recruitment remains at a very low level, with an historical minimum value in the North Sea. Silver eel time series have been analysed to identify patterns in abundance trends. These analyses are exploratory and have enabled us to test certain statistical methods and their limitations for analysing temporal series on silver eels. Although they give us an initial idea of trends in silver eel abundance, their results should be treated with caution. In fact, several problems have been identified and these points need to be improved in order to be able to interpret the results. The trend of reported commercial landings shows a long-term continuing decline, from a level of around 10,000 t in the 1960s, reported commercial landings have now dropped to 2028 (glass eel + yellow eel + silver eel) in 2022. The commercial glass eel fishery in 2022 was 60.1 t and 53.6 t in 2023. Reported landings from yellow and silver eel commercial fisheries (Y, S, YS) add up to 2914 t in 2021 and 2437 t in 2022. Spain was the only country allowing a recreational catch of glass eel, with landings estimated at 0.72 t in 2022 and 1.32 t in 2023. Reported recreational land-ings for yellow and silver eel combined were 240 t for 2021 (11 countries reporting) and 249 t for 2022. Progress with regards to the ‘road map’ developed within WKFEA was evaluated. The returns from the three questionnaires distributed by WKSMEEL to WGEEL members were summarised. In relation to the progress of the WKFEA roadmap, item 1; the inclusion of biological data is advanced with biometry data included in the annual data call. Item 2 relates to the reconstruction of the landings data and a workshop will take place in December 2023. Items 3 and 4 are also in progress, the Spatial database and Model for Eel (WKSMEEL) workshop was held in June 2023 with a follow up workshop planned for October 2023. A questionnaire for 3 topics (electrofish-ing, hydrographic network, and river obstructions & hydropower) was circulated to WGEEL members in August 2023. Of the 21 countries who responded, a large majority carry out electro-fishing, have available hydrographic networks and hold some information of obstructions to migration. However, it was recognised that considerable effort and resources will be required before the available data could be collated.publishedVersio

Chemical synthesis of silver nanoparticles for solar cell applications

A novel approach to fabricate silver nanoparticles for light trapping applications in silicon based solar cells has been demonstrated. Silver nanoparticles of various sizes have been synthesized by chemical reduction reactions. The particle size in the colloidal solutions was varied by using two different reducing compounds in addition to altering the compositions of the mixtures. In the present work, deposition of the silver nanoparticles onto a conventional bulk silicon solar cell shows an increase in the quantum efficiency at longer wavelengths, indicating the utilization of incident radiation that is normally lost in poor absorbing silicon (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)acceptedVersio

[Report from] Joint EIFAAC/ICES/GFCM Workinggroup on eels (WGEEL)

publishedVersio

[Report from] Joint EIFAAC/ICES/GFCM Workinggroup on eels (WGEEL)

Source at https://www.ices.dk/Science/publications/Pages/Scientific-reports.aspx