dark fleets

AI is turning a spotlight on the world’s dark fleets—ships that turn off their identification transponder tags—illuminating the surprisingly high number of vessels that operate anonymously. The data offers new insights into the possible extent of illegal fishing, for example, and the technology may have major political implications for the enforcement of sanctions.

The study, led by Global Fishing Watch, revealed that 75% of the world’s industrial fishing vessels are not tracked publicly. Maritime watchers have relied on an automatic identification system (AIS) that tracks ship radio activity across the globe. A ship’s crew can simply turn off the AIS transponder when it doesn’t want to be tracked.  The preponderance of dark fleets operate in Asia. Two million gigabytes of data was culled from five years of radar information from a pair of Copernicus Sentinel satellites along with GPS tracking. By applying AI to the data, researchers were able to determine which vessels were engaged in fishing. The study period applied to 2017-2021 and across the coastal waters of six continents.

The study also revealed that 25% of transport and energy vessel activity was missing from tracking systems. The Atlantic Council estimates that since Russia’s invasion of Ukraine, the number of dark fleet vessels has grown “explosively” to 1,400 ships.

“Their presence poses considerable risks to other ships,” says the Atlantic Council. “In addition to serving the transportation needs of Russia (as wells as Iran, North Korea and Venezuela), the shadow fleet form quintessential ‘gray zone’ aggression, causing tangible harm that target countries can do little to punish.”


More specifically, 19 dark fleet vessels have visited the Vostochny Port in Russia since August, 2023, according to a Center for Strategic and International Studies (CSIS) review of publicly available satellite data, and they are thought to be loaded with ammunition from North Korea.

From a fisheries perspective, the Global Fishing Watch study revealed that some dark fleet vessels are fishing illegally in protected maritime preserves, posing a challenge to conservation efforts. Mapping vessel traffic also will improve estimates of greenhouse gas emissions at sea as well as pollution events wherein offending parties can be called to account. The AI-enabled study is probably the most comprehensive public picture of the global industrial fishing available.

The Global Fishing Watch AI study indicates that industrial activity on the world’s oceans has been underestimated. For example, the study found that the number of green offshore energy projects doubled during the five-year period with wind turbines now outnumbering oil platforms. China has taken the lead in this regard by increasing its number of ocean wind farms by 900 percent.

“Growth on our oceans has largely been hidden from view,” says David Kroodsma, the nonprofit’s director of research and innovation.” This study helps eliminate the blind spots and sheds light on the breadth and intensity of human activity at sea.”