Report of the Working Group on Effectiveness of Recovery Actions for Atlantic Salmon (WGERAAS)

The Working Group on Effectiveness of Recovery Actions for Atlantic Salmon (WGER-AAS) was established in 2012 in response to a question to ICES Working Group on North Atlantic Salmon (WGNAS) by the North Atlantic Salmon Conservation Organisation (NASCO). The NASCO question resulted in a new ToR for WGNAS: “provide a review of examples of successes and failures in wild salmon restoration and rehabilitation and develop a classification of activities which could be recommended under various condi-tions or threats to the persistence of populations”.WGERAAS met on 18–22 February 2013 in Belfast, Northern Ireland; 12–16 May 2014 at ICES HQ, Copenhagen, Denmark; and on 10–12 November 2015 for a third and final time at that same location.At the 2013 meeting the Working Group decided that the development of a ‘classification system’ for rebuilding and recovery actions for Atlantic salmon (ToR a) would be best achieved by the development of a river-specific database; ‘Database on Effectiveness of Recovery Actions for Atlantic Salmon’ (DBERAAS). Local experts provided a range-wide overview of conservation status, programme goals, population stressors and the benefits of recovery actions. To further highlight the results from DBERAAS detailed case studies were compiled and presented on a number of rivers, providing ‘on-the-ground’ examples of the effects of stressors, benefit of actions, and the results of recovery and rebuilding programmes.An analysis of DBERAAS suggested that Climate Change (resulting in low marine sur-vival), barriers to migration, and habitat destruction were the most common stressors having a high or very high negative impact on Atlantic salmon populations. Improve-ments in river connectivity, improvements in water quality, and habitat restoration were the three actions most likely to have a high or very high benefit to recovery and restora-tion actions. The case studies were largely in agreement with the results from DBERAAS, and further highlighted that successful restoration and recovery actions are generally characterised by being conducted on stocks experiencing relatively high marine survival, with few stressors acting on the stock thereby reducing synergistic and additive effects, with actions addressing most or all stressors, and not relying (solely) on stocking.