Bottom trawl fishing footprints on the world’s continental shelves

Authors: Ricardo O. Amoroso, C. Roland Pitcher, A.D. Rijnsdorp, Robert A. McConnaughey, Ana M. Parma, Petri Suuronen, Ole Ritzau Eigaard, François Bastardie, Niels T. Hintzen, Franziska Althaus, Susan Baird, Jenny Black, Lene Buhl‐Mortensen, Alexander B. Campbell, Rui Catarino, Jeremy S. Collie, James H. Cowan, Deon Durholtz, Nadia Engstrom, Tracey P. Fairweather, Heino O. Fock, Richard B. Ford, Patricio Gálvez, H.D. Gerritsen, María Eva Góngora, Jessica A. González, Jan Geert Hiddink, Kathryn M. Hughes, Steven S. Intelmann, Chris Jenkins, Patrik Jönsson, Paulus Kainge, Mervi Kangas, Johannes N. Kathena, Stefanos Kavadas, R. W. Leslie, Steve Lewis, Mathieu Lundy, David A. Makin, Julie Martin, Tessa Mazor, Genoveva Gonzalez‐Mirelis, Stephen J. Newman, Nadia Papadopoulou, Paulette Posen, Wayne Rochester, Tommaso Russo, Antonello Sala, Jayson M. Semmens, Cristina Silva, A. Tsolos, Bart Vanelslander, Corey B. Wakefield, Brent Alexander Wood, Ray Hilborn, Michel J. Kaiser, Simon Jennings - Proceedings of the National Academy of Sciences, PNAS 2018 cited by 327

study area was trawled, and 86% was not trawled. Trawling activity was aggregated; the most intensively trawled areas accounting for 90% of activity comprised 77% of footprint on average. Regional swept area ratio (SAR; ratio of total swept area trawled annually to total area of region, a metric of trawling intensity) and footprint area were related, providing an approach to estimate regional trawling footprints when high-resolution spatial data are unavailable. If SAR was ≤0.1, as in 8 of 24 regions, there was >95% probability that >90% of seabed was not trawled. If SAR was 7.9, equal to the highest SAR recorded, there was >95% probability that >70% of seabed was trawled. Footprints were smaller and SAR was ≤0.25 in regions where fishing rates consistently met international sustainability benchmarks for fish stocks, implying collateral environmental benefits from sustainable fishing.