Claude Belpaire INBO Olga Haenen CVI Photo Rollin
Claude Belpaire, INBO Olga Haenen, CVI Photo: Rollin Verlinde ICES Workshop of a Planning Group on the Monitoring of Eel Quality: “Development of standardized and harmonized protocols for the estimation of eel quality. ” (WKPGMEQ)
Objectives Progress towards the development of standardised and harmonised protocols for the estimation of the quality of the European eel Anguilla anguilla Specifically with regard to the bioaccumulation of contaminants the presence of diseases, including parasites
Where, when and who Meeting at the Research Institute Nature and Forest (INBO) Brussels, Belgium: 20– 22 January 2015 31 participants (21 attendees and 10 remote participants) representing 13 countries. Chaired by: Claude Belpaire (INBO, Belgium) and Olga Haenen (CVI, part of WUR, the Netherlands)
General decline of the species Eel recruitment is going down since ca 35 years (except very recently). -> Endangered status and increased protection.
Eel stock decline Possible causes include River Vilaine glass eel fisheries • Fisheries French yellow eel fisheries Recreational fisheries Lough Neagh silver eel fisheries Briand et al. (2006) Evans et al. (2006)
Eel stock decline Possible causes include River IJzer around 1900 • Fisheries • Habitat degradation River IJzer around 1970 Embankment
Eel stock decline Possible causes include • Fisheries • Habitat degradation • Migration obstructions e. g. sluices, dams, weirs, impingment, turbines, drainage pumps, … Silver eel killed by pump River Velpe at Hoeleden River Dender at Aalst
Eel stock decline Possible causes include • • Fisheries Habitat degradation Migration obstructions Water quality and pollution Water pollution Toxic compounds
Eel stock decline Possible causes include Anguillicola crassus • • Fisheries Habitat degradation Migration obstructions Water quality and pollution • Diseases Life cycle of A. crassus Thomas (1993)
Eel stock decline Possible causes include Cormorants • • Fisheries Habitat degradation Migration obstructions Water quality and pollution • Diseases • Predation Photo Hugo Verreycken Photo John Cooper
Eel stock decline Possible causes include • • Fisheries Habitat degradation Migration obstructions Water quality and pollution • Diseases • Predation • Climatic change and oceanic changes Gulf stream and North Atlantic Drift British Society for Geomorphology
Insufficient quantity or quality of spawners Stock decline
Framework To enable a better assessment of the impact of contaminants and diseases which may effect spawner biomass and reproductive success of eels, the implementation of national routine monitoring programs is required (ICES, 2012 b). ICES recommended taking up an obligation of the Member States (MS) for the realization of routine monitoring of lipid levels, contamination and diseases as part of the Eel Regulation. Advice for planning future reporting of the assessment of the quality of local stocks, specifically for calculating the Reproductive Potential of silver eels and the Eel Quality Index (EQI) of yellow eels in each Eel Management Unit (EMU).
Measuring eel quality is recommended … Eel Regulation Data Collection Framework (DCF) Water Framework Directive (WFD) Marine Strategy Framework Directive Human health issues (Food safety) Reports of the Joint EIFAAC/ICES Working Group on Eels (WGEEL) OSPAR Results availability and need of an international database
EU Dioxin Regulation Europe: EU Dioxin Regulation (Com Reg EU No 1259/2011) came into force on 1 January 2012. 8 countries. 38% non-compliant. Max 13223 ng/g ww. Threshold: Sum ICES 6 PCBS 300 ng/g ww
. . . Absence of guidance: Common procedures to estimate eel quality at an international level are not available Methods of sampling, sample handling procedures, the range of chemical contaminants and other parameters measured, and the protocols for data reporting differ significantly among studies/ countries. Results are presented in different formats Raw data are usually unavailable to the international community.
Workflow for integrating eel quality indicators in the international advice for stock management and restoration.
About sampling and treatment on site : How to …. . Identify Species, Life stages and Gender Select appropriate sites Length, weight and age issues Size of the sample, number of eels to be analysed. Season of sampling Sampling methods and impact Holding and hygienic measures Label, store and preserve
About using indices for measuring eel condition and fitness. How to measure and express … Eel condition Lipids Gross energy Gonadosomatic Index (GSI) Hepatosomatic Index (HSI) Reproduction Index
About sampling and analysis of contaminants : How to …. . Killing and anesthetizing Tissue sampling Storage and general treatment of the samples Analytical measurements Detection limits Quality assurance and quality control
About interpretation, visualisation and assessment : Existing methods …. . Eel Quality Classes Eel Quality Index (EQI), derived from the Eel Quality Classes IMBI: individual mean (multi-metal) bioaccumulation index The Eel Patho-Index (EPI), a Health Status Classification System Reproductive potential in silver eels Effective Spawner Escapement as evaluated in Irish rivers
Eel Quality Index for Contaminants Europe: In the framework of international assessments and advice ICES (2010, 2011, 2012) developed an Eel Quality Index for Contaminants. Figure. Demonstration of the Eel Quality Index of Contaminants (EQICOM) based on ICES 6 PCBs of 1010 yellow or silver eels from 313 sites over 7 countries from Belpaire et al (2012, unpublished). (ICES, 2012).
About parasitic diseases How to diagnose and report …. . Anguillicoloides crassus (swimbladder nematode) Pseudodactylogyrus spp. blood parasites such as trypanosomes… Clinical signs and sampling methods, # of eels Preservation of parasites for identification How to report
About viral diseases How to diagnose and report …. . Clinical signs of infections Methods of sampling (in field or at lab) in which season Diagnostic tests for viruses: Ang. HV 1, EVEX, a. o. PCR methods Virus isolation immunological methods Ang. HV 1 How to report EVEX
About bacterial diseases How to diagnose and report …. . Clinical signs and sampling methods, # of eels Vibrio vulnificus Edwardsiella tarda Pseudomonas anguilliseptica Aeromonas salmonicida atypical Aeromonas hydrophila/sobria Flavobacterium columnare Mycobacterium marinum Bacterial isolation and identification methods Hygiene precautions How to report
Perspectives of using biomarkers of effects to assess eel health Preliminary discussion Listing perspectives Literature overview
Conclusions (1) Current methods differ between Member States and are not harmonised. Most data have been collected for human health considerations and the assessment of habitat quality. Disease monitoring is still only carried out in a few countries and is focused on mainly parasites, and in some cases also eel viruses. International assessment of the quality of eel stocks would only be possible if raw data was accessible.
Conclusions (2) The workshop made good progress in elaborating common best practice for evaluating eel quality. WKPGMEQ recognizes the need to support and initiate international coordinated research to allow development of suitable set of biomarkers to assess eel health (e. g. in terms of survival, migration and reproduction capacity). The workshop provided requirement and recommendations for assessing eel quality under existing international frameworks and agreed the need of an international database.
Recommendations Harmonised methods for eel quality assessments and reporting should be implemented by the Member States. Take up an obligation of the Member States for the realization of routine monitoring by Member States, of lipid levels, contamination and diseases in the Eel Regulation. Considering the current gaps in knowledge to fully assess the effects of current levels of contaminants on eel, monitoring efforts should be coupled to other research actions (need of an internationally coordinated research project) Raw data should be made available to the international community through WGEel for inclusion in the Eel Quality Database. The long-term management of the Eel Quality Database needs a structural basis and should be managed at an international level.
Report is available at ICES Website ICES WKPGMEQ REPORT 2014 Thank you for your attention! (Pictures of this presentation © CVI/INBO)
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