Caitlin Frankish¹, Tycho Anker-Nilssen², Jens Åström², Vegard S Bråthen², Francis Daunt³, Oskar Bjørnstad⁴, Maria I Bogdanova⁵, Robert Barrett⁶, Sébastien Descamps¹, Per Fauchald⁷, Benjamin Merkel¹, Mark Bolton⁸, Børge Moe², Thierry Boulinier⁹, Svenja Neumann¹, Hallvard Strøm¹, Ingar Bringsvor², Arnaud Tarroux⁷, Lila Buckingham², Jan Ove Bustnes², John Chardine¹⁰, Olivier Chastel⁹, Lorraine Chivers¹¹, Signe Christensen-Dalsgaard², Manon Clairbaux¹², Kendrew Colhoun¹³, Johannis Danielsen¹⁴, Nina Dehnhard², Kyle Elliott¹⁵, Kjell Einar Erikstad², Alexey Ezhov¹⁶, Annette Fayet², David Fifield¹⁷, Jerome Fort¹⁸, Morten Frederiksen¹⁹, Maria Gavrilo²⁰, Grant Gilchrist²¹, Marianne Gousy-Leblanc²², David Gremillet⁹, Tim Guilford²³, Gunnar Þór Hallgrímsson²⁴, Erpur Hansen²⁵, April Hedd²⁶, Hálfdán Helgason²⁷, Mark Jessopp¹², Malin Kjellstadli Johansen²⁸, Jón Einar Jónsson²⁹, Yann Kolbeinsson³⁰, Yuri Krasnov¹⁶, Kate Layton-Matthews³¹, Jannie Linnebjerg³², Svein-Håkon Lorentsen², Mark Mallory³³, Flemming Merkel¹⁹, William A Montevecchi³⁴, Anders Mosbech¹⁹, Mark Newell³⁵, Stephen Newton¹³, Bergur Olsen¹⁴, Sunna Bjork Ragnarsdottir³⁶, Tone K Reiertsen⁷, Deryk Shaw³⁷, Robert Swann³⁸, Geir H Systad², Paul Thompson³⁹, Thorkell Lindberg Thorarinsson³⁰, Ekaterina Tolmacheva⁴⁰, Sarah Wanless³⁵, Jorg Welcker⁴¹, Katarzyna Wojczulanis-Jakubas⁴² and Jamie Darby¹², (1)Norwegian Polar Institute, Tromsø, Norway, (2)Norwegian Institute for Nature Research, Trondheim, Norway, (3)UK Centre for Ecology and Hydrology, Edinburgh, United Kingdom, (4)Karmøy Ringmerkingsgruppe, Skudeneshavn, Norway, (5)Centre for Ecology and Hydrology, Penicuik, United Kingdom, (6)University of Tromsø, Tromsø, Norway, (7)Norwegian Institute for Nature Research, Tromsø, Norway, (8)RSPB, Sandy, United Kingdom, (9)CNRS, Montpellier, France, (10)Environment Canada, New Brunswick, Canada, (11)Queen's University, Belfast, Ireland, (12)University College Cork, Cork, Ireland, (13)Birdwatch Ireland, Dublin, Ireland, (14)Faroe Marine Research Institute, Torshavn, Faroe Islands, (15)Mcgill, Ste Anne-de-Bellevue, Canada, (16)Murmansk Marine Biological Institute, Murmansk, Russia, (17)Environment and Climate Change Canada, Newfoundland, Canada, (18)La Rochelle Université, La Rochelle, France, (19)Aarhus University, Roskilde, Denmark, (20)Arctic and Antarctic Research Institute, Saint-Petersburg, Russia, (21)Environment and Climate Change Canada, Ottawa, Canada, (22)McGill University, Montreal, Canada, (23)Oxford University, Oxford, United Kingdom, (24)University of Iceland, Reykjavik, Iceland, (25)South Iceland Nature Research Centre, Vestmannaeyjar, Iceland, (26)Climate and Environmental Change, Newfoundland and Labrador, Canada, (27)East Iceland Nature Research Centre, Neskaupstaður, Iceland, (28)Norwegian Polar Institute, Trom, Norway, (29)University of Iceland's Research Center, Stykkishólmur, Iceland, (30)Northeast Iceland Nature Research Centre, Húsavík, Iceland, (31)Norwegian Institute for Nature Research, Oslo, Norway, (32)DHI Denmark, Copenhagen, Denmark, (33)Acadia University, Nova Scotia, Canada, (34)Memorial University of Newfoundland, Newfoundland, Canada, (35)UK Centre for Ecology & Hydrology, Penicuik, United Kingdom, (36)Iceland Institute of Natural Research, Garðabær, Iceland, (37)Fair Isle Bird Observatory, Fair Isle, United Kingdom, (38)British Trust for Ornithology, Turo, United Kingdom, (39)University of Aberdeen, Cromarty, United Kingdom, (40)Murmansk Marine Biological Institute, Murmasnk, Russia, (41)BioConsult, Husum, Germany, (42)University of Gdansk, Gdansk, Poland