SC/24/FI/10 ICES WGMME REPORT 2017 ICES ADVISORY COMMITTEE ICES CM 2017/ACOM:27 Report of the Working Group on Marine Mammal Ecology (WGMME) 6–9 February 2017 St Andrews, Scotland, UK SC/24/FI/10 International Council for the Exploration of the Sea Conseil International pour l’Exploration de la Mer H. C. Andersens Boulevard 44–46 DK-1553 Copenhagen V Denmark Telephone (+45) 33 38 67 00 Telefax (+45) 33 93 42 15 www.ices.dk [email protected] Recommended format for purposes of citation: ICES. 2017. Report of the Working Group on Marine Mammal Ecology (WGMME), 6– 9 February 2017, St Andrews, Scotland, UK. ICES CM 2017/ACOM:27. 102 pp. For permission to reproduce material from this publication, please apply to the Gen- eral Secretary. The document is a report of an Expert Group under the auspices of the International Council for the Exploration of the Sea and does not necessarily represent the views of the Council. © 2017 International Council for the Exploration of the Sea SC/24/FI/10 ICES WGMME REPORT 2017 | i Contents Executive Summary ............................................................................................................... 5 1 Introduction .................................................................................................................... 6 2 ToR A. Review and report on any new information on population abundance, population/stock structure, management frameworks (including indicators and targets for MSFD assessments), and anthropogenic threats to individual health and population status (e.g. plastics) ............................................................................................................................ 7 2.1 New abundance information .............................................................................. 7 2.1.1 Seals ........................................................................................................... 7 2.1.2 Cetaceans ................................................................................................ 10 2.2 New information of stock structure ................................................................. 15 2.3 New information on anthropogenic threats.................................................... 15 2.3.1 Fishery bycatch ....................................................................................... 15 2.3.2 Pollution: persistent organic pollutants and toxic elements ............ 17 2.3.3 Plastics and other marine debris .......................................................... 18 2.3.4 Underwater noise (offshore construction, shipping, aquaculture) ............................................................................................ 22 2.3.5 Ship strikes .............................................................................................. 25 2.3.6 Cumulative impacts............................................................................... 25 2.4 References ............................................................................................................ 26 3 Tor B. Review and update the criteria for assessment of cetaceans in the context of the MSFD ............................................................................................. 34 3.1 References ............................................................................................................ 37 4 ToR C. Review current issues in relation to direct impacts of seals on fisheries ......................................................................................................................... 39 4.1 Introduction ......................................................................................................... 39 4.2 Seal species of concern and “rogue seals” ....................................................... 40 4.3 Consequences of depredation ........................................................................... 41 Grey, ringed, and harbour seals ............................................................................ 45 Cod, salmonids, whitefish, vendace, pike, pike perch, eel, bream, flatfishes, herring, lumpsucker, mackerel, wrasse, etc. ............................. 45 Passive gear; Trapnets, hooks, nets ...................................................................... 45 Swedish coast ....................................................................................................... 45 Greater North Sea; Baltic Sea .............................................................................. 45 33 300 000 SEK in 2014 ...................................................................................... 45 Experiments with cod pots. Economical compensation 16 m SEK in 2014. Protective hunt of seals ................................................................... 45 (Havs- och vattenmyndigheten, 2014) ................................................................. 45 4.4 Mitigation ............................................................................................................ 49 SC/24/FI/10 ii | ICES WGMME REPORT 2017 4.4.1 Gear and method optimisation ............................................................ 49 4.4.2 ADDs ....................................................................................................... 50 4.4.3 Lethal removal of seals .......................................................................... 51 4.4.4 Other ........................................................................................................ 51 4.4.5 Conclusion .............................................................................................. 52 4.5 Direct impact of seals on fisheries-a case study from Latvia in 2016 .......... 52 4.5.1 Summary ................................................................................................. 53 4.6 References ............................................................................................................ 55 5 ToR D. Update the database for seals ...................................................................... 59 5.1 Historical context ................................................................................................ 59 5.2 ‘ICES seal database’ ............................................................................................ 60 5.2.1 Area of relevance ................................................................................... 60 5.2.2 Current status ......................................................................................... 60 5.3 ‘OSPAR seal database’ ....................................................................................... 61 5.3.1 Area of relevance ................................................................................... 61 5.3.2 Current status ......................................................................................... 61 5.4 Future database concerns .................................................................................. 61 5.5 Recommendation ................................................................................................ 62 5.6 References ............................................................................................................ 62 6 ToR E. Update assessments of offshore cetaceans based on new results from the SCANS-III survey ....................................................................................... 63 6.1 Consideration of new information ................................................................... 70 6.1.1 Harbour porpoise................................................................................... 71 6.1.2 Bottlenose dolphin ................................................................................. 78 6.1.3 White-beaked dolphin ........................................................................... 78 6.1.4 Common and striped dolphins ............................................................ 79 6.1.5 Long-finned pilot whale ....................................................................... 79 6.1.6 Beaked whales (all species)................................................................... 80 6.1.7 Sperm whale ........................................................................................... 80 6.1.8 Minke whale ........................................................................................... 80 6.1.9 Fin whale ................................................................................................. 80 6.2 Power to detect trends ....................................................................................... 81 6.3 Concluding remarks - lessons learned from the SCANS experience........... 82 6.4 References ............................................................................................................ 82 7 ToR F. Contribute regional text to new ecosystem overviews for (i) Iceland, (ii) Norwegian Seas, (iii) Baltic, (iv) Azorean ecoregion and (v) the Oceanic Northeast Atlantic ecoregion ......................................................... 84 7.1 ToR f (i) Iceland ................................................................................................... 84 7.1.1 References ............................................................................................... 86 7.2 ToR f (ii) Norwegian waters .............................................................................. 86 7.2.1 References ............................................................................................... 87 7.3 ToR f (iii) Baltic...................................................................................................