January 18, 2024 — The fillet of flounder sitting on your plate comes with a severe environmental cost. To catch it, a ship running on fossil fuels spewed greenhouse gases as it dragged a trawl net across the seafloor, devastating the ecosystems in its path. Obvious enough. But new research shows that the consequences extend even further: Trawl nets are hauling up both food and a huge amount of carbon that’s supposed to be sequestered in the murky depths.
In a paper publishing in the journal Frontiers in Marine Science, researchers have tallied up an estimate of how much seafloor carbon the bottom-trawling industry stirs into the water and how much of that is released into the air as CO2 each year, exacerbating global warming. It turns out to be double the annual fossil fuel emissions produced by the entire world’s 4 million–vessel fishing fleet.
“At least 55 to 60 percent of the CO2 created by trawling—scraping the seafloor—is going to come into the atmosphere within nine years,” says lead author and ecosystem ecologist Trisha Atwood, who focuses on carbon cycling at Utah State University and National Geographic’s Pristine Seas program. “It now suggests that countries should be looking at this industry, and that their carbon footprint goes a lot further than maybe they were thinking, just in terms of the amount of gas that they burned to get out to their fishing grounds.”