You might remember newspaper articles in 2021 claiming that towing nets over the seabed to catch fish (known as bottom trawling) releases as much carbon as all flights taken each year. It turns out that the assessment behind this claim overestimated how much CO₂ is released in the process of bottom trawling by 100 to 1,000 times.
Bottom-trawl fishing supplies one-quarter of fish landings globally and, as it occurs worldwide, is by far the most extensive way in which people disturb the seabed. Towing nets, chains and other heavy metal trawl gear along the seabed kills some of the clams, worms and starfish that live within it, but it also mixes and resuspends sediment in the water.
