Working Group on Science to Support Conservation, Restoration and Management of Diadromous Species (Outputs from 2023 Meeting) (WGDIAD)

The 2023 WGDIAD meeting took place from 12th to 13th September at the Palacio Euskalduna in Bilbao, Spain, in a hybrid format with both in-person and remote participation. The meeting brought together 22 participants from nine member states, who engaged in discussions on the conservation and management of diadromous species, focusing on updates from four key expert groups: WGEEL, WGNAS, WGBAST, and WGTRUTTA. The meeting addressed critical topics such as eel stock assessments, salmon life-cycle modelling, sea trout population management, and the current status of Baltic salmon stocks. A key presentation came from the Northern Hemisphere Pink Salmon Expert Group, which focused on the rapid and concerning range expansion of pink salmon (Oncorhynchus gorbuscha) into the North Atlantic and Arctic Oceans. Pink salmon, originally a Pacific species, has seen an unexpected increase in numbers in regions like Norway, Scotland, and even as far south as France. The group explored the ecological implications of this invasion, including potential competition with native species like Atlantic salmon and the effects on local ecosystems. The presentation also emphasized the importance of using tools like environmental DNA (eDNA) to monitor the spread of pink salmon and assess the long-term impacts of their establishment in non-native regions. Additional presentations included updates from the GenMeMo Project on smelt genetics in the German Bight and the DIADes Project, which integrates ecological and economic research for the improved management of diadromous species. These presentations stimulated discussions on how these findings could be integrated into stock assessments and management strategies for migratory freshwater fish. A major point of discussion during the meeting was the ongoing progress toward formalizing a Memorandum of Understanding (MoU) between the North Pacific Anadromous Fish Commission (NPAFC) and ICES, with a focus on fostering collaboration between Atlantic and Pacific salmon scientists. While progress has been slow, the meeting reaffirmed the commitment to building stronger ties through international collaboration. The meeting also addressed future leadership within WGDIAD, with co-chair Hugo Maxwell calling for nominations to replace Dennis Ensing, whose second three-year term is ending. Maxwell emphasized the importance of nominating early career scientists, with nominations requested before the end of November 2023. The 2023 WGDIAD meeting reinforced the group’s role in coordinating international efforts to tackle the complex challenges facing diadromous species, including climate change, habitat loss, and interspecies competition. The meeting highlighted the importance of continued international cooperation, innovative monitoring techniques, and adaptive management strategies to safeguard the future of diadromous species.