Bottom trawl fishing footprints on the world’s continental shelves

• Published in: Proceedings of the National Academy of Sciences
• Main Authors: Amoroso, Ricardo O., Pitcher, C. Roland, Rijnsdorp, Adriaan D., McConnaughey, Robert A., Parma, Ana M., Suuronen, Petri, Eigaard, Ole R., Bastardie, Francois, Hintzen, Niels T., Althaus, Franziska, Baird, Susan Jane, Black, Jenny, Buhl-Mortensen, Lene, Campbell, Alexander B., Catarino, Rui, Collie, Jeremy, Cowan Jr., James H., Durholtz, Deon, Engstrom, Nadia, Fairweather, Tracey P., Fock, Heino O., Ford, Richard, Gálvez, Patricio A., Gerritsen, Hans, Góngora, María Eva, González, Jessica A., Hiddink, Jan G., Hughes, Kathryn M., Intelmann, Steven S., Jenkins, Chris, Jonsson, Patrik, Kainge, Paulus, Kangas, Mervi, Kathena, Johannes N., Kavadas, Stefanos, Leslie, Rob W., Lewis, Steve G., Lundy, Mathieu, Makin, David, Martin, Julie, Mazor, Tessa, Gonzalez-Mirelis, Genoveva, Newman, Stephen J., Papadopoulou, Nadia, Posen, Paulette E., Rochester, Wayne, Russo, Tommaso, Sala, Antonello, Semmens, Jayson M., Silva, Cristina, Tsolos, Angelo, Vanelslander, Bart, Wakefield, Corey B., Wood, Brent A., Hilborn, Ray, Kaiser, Michel J., Jennings, Simon
• Other Authors: Fisheries and Aquatic Ecosystems
• Format: Article in Journal/Newspaper
• Language: English
• Published: National Academy of Sciences 2018
• Subjects: fisheries; effort; footprint; habitat; seabed; Bering Sea; glacier; Alaska; Aleutian Islands
• Online Access: https://hdl.handle.net/20.500.12518/258; https://www.pnas.org/content/115/43/E10275

Publication history: Accepted - 23 August 2018; Published online - 8 October 2018. Bottom trawlers land around 19 million tons of fish and invertebrates annually, almost one-quarter of wild marine landings. The extent of bottom trawling footprint (seabed area trawled at least once in a specified region and time period) is often contested but poorly described. We quantify footprints using high-resolution satellite vessel monitoring system (VMS) and logbook data on 24 continental shelves and slopes to 1,000-m depth over at least 2 years. Trawling footprint varied markedly among regions: from <10% of seabed area in Australian and New Zealand waters, the Aleutian Islands, East Bering Sea, South Chile, and Gulf of Alaska to >50% in some European seas. Overall, 14% of the 7.8 million-km2 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 highresolution spatial data are unavailable. If SAR was ≤0.1, as in 8 of 24 regions, therewas >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. Funding for meetings of the study group and salary support for R.O.A. were provided by the following: David and Lucile Packard Foundation; the Walton Family Foundation; the Alaska Seafood Cooperative; American Seafoods Group US; Blumar Seafoods Denmark; Clearwater Seafoods Inc.; Espersen Group; Glacier Fish Company LLC US; Gortons ...