Recent scientific work outlines the severe consequences the practice of bottom trawling has on loose sediment on the ocean floor. Bottom trawling is a widespread industrial fishing practice that involves dragging heavy nets, large metal doors and chains over the seafloor to catch fish. Although previous studies documented the direct impacts of bottom trawling on corals, sponges, fishes and other animals, an understanding of the global impact of this practice on the seabed remained unclear until now. The first calculation of how much of the seabed is resuspended (or stirred up) by bottom-trawling shows that the sediment mass is approximately the same amount of all sediment being deposited on the world’s continental shelves by rivers each year (almost 22 gigatons).
Understanding regional and global magnitudes of resuspended sediment is an essential baseline for the analysis of the environmental consequences for continental shelf habitats and their associated seafloor and open-ocean ecosystems. The scientists found new ways to look at and into the seabed to document the evidence of the effects of bottom trawling.