International Council for the Exploration of the Sea
ICES WGDEC Report 2019.pdf (12.61 MB)

Report of the ICES/NAFO Joint Working Group on Deep-water Ecology (WGDEC)

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posted on 2019-01-01, 00:00 authored by ICESICES

The joint ICES/NAFO Working Group on Deep-water Ecology (WGDEC) collates new infor-mation on the distribution of Vulnerable Marine Ecosystems (VMEs) for use in annual ICES advisory processes and the development of new methods/techniques to further our understanding of deep-sea ecosystems, and further suggests novel management tools to ensure human activities do not adversely affect them.

This year, a total of 26 379 new presence records were submitted through the ICES VME data call in 2018/19 and included within the ICES VME database, plus 314 absence records. This in-formation was prepared by WGDEC for ICES to be able to provide advice on the distribution of VMEs in the North Atlantic. All presence records from the VME database were presented as outputs from the VME weighting system, showing the likelihood of VMEs being encountered on the seabed along with an associated confidence assessment.

Further to this work, the group’s additional objectives in 2019 were to continue to review how to best define Good Environmental Status (GES) for deep-sea habitats; to investigate methods to further develop the VME weighting algorithm; and to review options for the use of predictive modelling techniques to provide wider coverage of potential VME distribution, in collaboration with the Working Group on Marine Habitat Mapping (WGMHM) who met jointly with WGDEC this year.

To these goals, WGDEC reviewed work conducted by the ICES Working Group on Fisheries Benthic Impact and Trade-offs (WGFBIT) on the evaluation of benthic impacts from fisheries at a regional scale, and further reviewed progress assessing GES in deep-sea areas within the pro-jects ATLAS (Horizon 2020) and IDEM (DG Environment). It was identified that testing the approach developed by WGFBIT, building upon the ICES 2017 indicators and assessment frame-work, for deep-sea habitats would be beneficial, initially using case study examples from the ATLAS project, and outputs would be further reviewed at WGDEC 2020.

One of the key tools developed by WGDEC over the last 4 years is the VME weighting algorithm which aims to show the known and likely distribution of VMEs, based on underlying VME hab-itat and indicator data from the VME database. There have been some concerns raised about the method underlying the weighting algorithm, and as such WGDEC explored two supplementary methods this year. The first method was kernel density estimation (KDE), a method adopted by the Northwest Atlantic Fisheries Organization (NAFO). This was tested on trawl data from the VME database for 1) all VME indicators and 2) only for sea-pens. Whilst the first trial tended to reflect sampling effort over VME hotspots, the second trial for sea-pens was more successful. There are, however, limitations with the approach and it was agreed that further work could be explored to standardise the data to optimise the application of these tools to data in the ICES VME database. The second method reviewed the use of predictive modelling techniques to sup-port understanding of area of likely VME distribution. Modelling methods were not tested this year, but a series of considerations for model creation and criteria for model use were identified, to be trialled at WGDEC 2020.

Finally, to support advice to the European Commission for application of the EU deep-sea access regulations, WGDEC reviewed the list of VME indicators in Annex III of the regulations and proposed additional VME habitat sub-types and representative taxa for certain habitats. Additional changes to representative taxa will be discussed through an intersessional sub-group, to ensure agreement by taxa specialists, for submission to ICES by September 2019.


Published under the auspices of the following ICES Steering Group or Committee


Published under the auspices of the following ICES Expert Group or Strategic Initiative



ICES Scientific Reports





Contributors (Editors)

Laura Robson

Contributors (Authors)

James Albrecht; Lindsay Beazley; Pål Buhl-Mortensen; Oisín Callery; Marina Carreiro Silva; Ana Colaço; Neil Golding; Anthony Grehan; Hilmar Hinz; Kerry Howell; Ellen Kenchington; Vladimir Khlivnoi; Anna Metaxas; Covadonga Orejas; Chris Pham; Carlos Pinto; David Stirling; Sebastian Valanko; Ida Vee; Joana Xavier



Recommended citation

ICES. 2019. ICES/NAFO Joint Working Group on Deep-water Ecology (WGDEC). ICES Scientific Reports. 1:56. 119 pp.

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