Are we ready to track climate‐driven shifts in marine species across international boundaries? ‐ A global survey of scientific bottom trawl data
Authors: A. Maureaud Aurore , Frelat Romain , Pécuchet Laurène , Shackell Nancy , Mérigot Bastien , Pinsky Malin L. , Amador Kofi , Anderson Sean C. , Arkhipkin Alexander , Auber Arnaud , Barri Iça , Bell Richard J. , Belmaker Jonathan , Beukhof Esther , Camara Mohamed L. , Guevara‐Carrasco Renato , Choi Junghwa , Christensen Helle T. , Conner Jason , Cubillos Luis A. , Diadhiou Hamet D. , Edelist Dori , Emblemsvåg Margrete , Ernst Billy , Fairweather Tracey P. , Fock Heino O. , Friedland Kevin D. , Garcia Camilo B. , Gascuel Didier , Gislason Henrik , Goren Menachem , Guitton Jérôme , Jouffre Didier , Hattab Tarek , Hidalgo Manuel , Kathena Johannes N. , Knuckey Ian , Kidé Saïkou O. , Koen‐Alonso Mariano , Koopman Matt , Kulik Vladimir , León Jacqueline Palacios , Levitt‐Barmats Ya’arit , Lindegren Martin , Llope Marcos , Massiot‐Granier Félix , Masski Hicham , McLean Matthew , Meissa Beyah , Mérillet Laurène , Mihneva Vesselina , Nunoo Francis K. E. , O'Driscoll Richard , O'Leary Cecilia A. , Petrova Elitsa , Ramos Jorge E. , Refes Wahid , Román‐Marcote Esther , Siegstad Helle , Sobrino Ignacio , Sólmundsson Jón , Sonin Oren , Spies Ingrid , Steingrund Petur , Stephenson Fabrice , Stern Nir , Tserkova Feriha , Tserpes Georges , Tzanatos Evangelos , van Rijn Itai , van Zwieten Paul A. M. , Vasilakopoulos Paraskevas , Yepsen Daniela V. , Ziegler Philippe , T. Thorson James 
Published: October 2020

Marine biota are redistributing at a rapid pace in response to climate change and shifting seascapes. While changes in fish populations and community structure threaten the sustainability of fisheries, our capacity to adapt by tracking and projecting marine species remains a challenge due to data discontinuities in biological observations, lack of data availability, and mismatch between data and real species distributions. To assess the extent of this challenge, we review the global status and accessibility of ongoing scientific bottom trawl surveys. In total, we gathered metadata for 283,925 samples from 95 surveys conducted regularly from 2001 to 2019. We identified that 59% of the metadata collected are not publicly available, highlighting that the availability of data is the most important challenge to assess species redistributions under global climate change. Given that the primary purpose of surveys is to provide independent data to inform stock assessment of commercially important populations, we further highlight that single surveys do not cover the full range of the main commercial demersal fish species. An average of 18 surveys is needed to cover at least 50% of species ranges, demonstrating the importance of combining multiple surveys to evaluate species range shifts. We assess the potential for combining surveys to track transboundary species redistributions and show that differences in sampling schemes and inconsistency in sampling can be overcome with spatio‐temporal modeling to follow species density redistributions. In light of our global assessment, we establish a framework for improving the management and conservation of transboundary and migrating marine demersal species. We provide directions to improve data availability and encourage countries to share survey data, to assess species vulnerabilities, and to support management adaptation in a time of climate‐driven ocean changes.