Three in Four Industrial Fishing Boats Are ‘Dark Vessels,’ Study Finds


A sprawling analysis of ocean traffic reveals that 75 percent of industrial fishing vessels are not publicly tracked, with the bulk of untracked fishing taking place in Southeast Asia.

For the study, researchers gathered a vast trove of satellite images from the European Space Agency, spanning 2017 to 2021, of coastal waters around the world. They compared images of ships with public records of their whereabouts to determine which vessels had not broadcast their locations. Researchers then trained a computer to identify which of those vessels were fishing boats.

The analysis found that three in four industrial fishing ships worldwide were so-called “dark vessels,” meaning they were not publicly tracked. It also identified a large number of dark vessels fishing in protected areas. Authors say that illegal fishing boats often turn off their transponders to hide their locations. The study, published in Nature, further revealed that industrial fishing in Asia is far more pervasive than public records would indicate.

Global Fishing Watch

“Publicly available data wrongly suggests that Asia and Europe have similar amounts of fishing within their borders, but our mapping reveals that Asia dominates — for every 10 fishing vessels we found on the water, seven were in Asia while only one was in Europe,” study coauthor Jennifer Raynor, of the University of Wisconsin-Madison, said in a statement.

Authors say that governments and watchdog groups could, as the study did, use satellite data to identify hotspots of illegal fishing or determine where industrial vessels are intruding on artisanal grounds. “Previously, this type of satellite monitoring was only available to those who could pay for it,” said David Kroodsma, director of research at Global Fishing Watch and co-lead author of the study. “Now it is freely available to all nations.”


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