Jonsson, Patrik
- Department of Aquatic Resources (SLU Aqua), Swedish University of Agricultural Sciences
Abstract
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 50% in some European seas. Overall, 14% of the 7.8 million-km(2) 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 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
Keywords
fisheries; effort; footprint; habitat; seabed
Published in
Proceedings of the National Academy of Sciences of the United States of America
2018, volume: 115, number: 43, pages: E10275-E10282
Publisher: NATL ACAD SCIENCES
SLU Authors
Global goals (SDG)
SDG2 Zero hunger
SDG14 Life below water
UKÄ Subject classification
Fish and Aquacultural Science
Publication identifier
- DOI: https://doi.org/10.1073/pnas.1802379115
Permanent link to this page (URI)
https://res.slu.se/id/publ/97006