期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:2022
卷号:119
期号:2
DOI:10.1073/pnas.2109449119
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Significance
We estimated the biological state of seabed sedimentary habitats, with specified uncertainty, in 24 trawled regions worldwide. Seabed status differed greatly among regions (from 0.25 to 0.999, relative to an untrawled state of 1); 15 regions had average status > 0.9. Two-thirds of all assessed seabed area was untrawled with status = 1, 93% had status > 0.8, but 1.5% had status = 0. The total area swept by trawling was a strong driver of regional status, providing a relationship to predict status from the regional estimated total amount of trawling. Seabed status is high in regions where fisheries are exploited sustainably—emphasizing that good fishery management contributes to better ecosystem outcomes—and, conversely, low status highlights regions needing improved management.
Bottom trawling is widespread globally and impacts seabed habitats. However, risks from trawling remain unquantified at large scales in most regions. We address these issues by synthesizing evidence on the impacts of different trawl-gear types, seabed recovery rates, and spatial distributions of trawling intensity in a quantitative indicator of biotic status (relative amount of pretrawling biota) for sedimentary habitats, where most bottom-trawling occurs, in 24 regions worldwide. Regional average status relative to an untrawled state (=1) was high (>0.9) in 15 regions, but <0.7 in three (European) regions and only 0.25 in the Adriatic Sea. Across all regions, 66% of seabed area was not trawled (status = 1), 1.5% was depleted (status = 0), and 93% had status > 0.8. These assessments are first order, based on parameters estimated with uncertainty from meta-analyses; we recommend regional analyses to refine parameters for local specificity. Nevertheless, our results are sufficiently robust to highlight regions needing more effective management to reduce exploitation and improve stock sustainability and seabed environmental status—while also showing seabed status was high (>0.95) in regions where catches of trawled fish stocks meet accepted benchmarks for sustainable exploitation, demonstrating that environmental benefits accrue from effective fisheries management. Furthermore, regional seabed status was related to the proportional area swept by trawling, enabling preliminary predictions of regional status when only the total amount of trawling is known. This research advances seascape-scale understanding of trawl impacts in regions around the world, enables quantitative assessment of sustainability risks, and facilitates implementation of an ecosystem approach to trawl fisheries management globally.