Report of the Working Group on Small Pelagic Fishes, their Ecosystems and Climate Impact (WGSPEC)

The Working Group on Small Pelagic Fishes, their Ecosystems and Climate Impact (WGSPEC) has held three meetings during 2016–2018 in Koblenz, Germany, and Plym-outh, UK, gathering scientists from the General Mediterranean Fisheries Council (GFMC) and ICES communities. The meetings were attended by experts in climate variability, physical oceanography, plankton, fish biology and fishery management. WGSPEC proac-tively contributed to a series of outreach activities to disseminate the new findings of the group, share views and facilitate discussion on the sustainable management of fish and fisheries under environmental change. These activities included (i) the co-organisation of a session at the international PICES/ICES Symposium on Drivers of Pelagic Fish Re-sources in March 2017, (ii) the publication of two articles in the special issue of Deep-Sea Research II including the Symposium proceedings and (iii) a contribution as co-editor of the same volume, (iv) the organisation of daily events addressed to students and to the public with an interest in the impact of environmental change on fish and fisheries, in conjunction with the 2017 and 2018 annual meetings.Expanding on the work done in previous years, during the reporting period WGSPEC reviewed the mechanisms and coupled ocean-atmosphere dynamics behind the ecosys-tem changes observed in the North Atlantic and Mediterranean, associated in particular with the fluctuations of the Atlantic Multidecadal Oscillation (AMO) and the contractions and expansions of the subpolar gyre (SPG). WGSPEC also showed that shifts in the North Atlantic Oscillation (NAO) and AMO phases were associated with significant changes in thermal preferences recently observed in Mediterranean stocks of small and medium pelagics, increasingly characterized by relatively warmer-water species.The outcome of the work done by WGSPEC under ToR a) and ToR b) was summarized in two papers published in Deep-Sea Research II and in one paper presently in preparation.Overall in 2016–2018, WGSPEC contributed to clarify mechanisms of the impact of cli-mate change on small and medium pelagics in different North Atlantic and Mediterrane-an regions, producing new findings that can be used to improve the management of those fish stocks. The group also addressed a recommendation received from the joint ICES/OSPAR/HELCOM Working Group on Seabirds (JWGBird) in 2017.