WarBrief Live | October 31, 2026 | Intelligence Tools
Global Fishing Watch is a free, public platform that maps fishing activity worldwide from satellite tracking data and radar imagery, letting analysts see vessels that official monitoring systems miss — including the so-called dark fleet.
Key Takeaways
- Global Fishing Watch merges vessel tracking broadcasts with satellite radar to map fishing activity worldwide, free of charge.
- A 2024 Nature study led by the organization found 72 to 76 percent of industrial fishing vessels are not publicly tracked.
- Its October 21, 2026 AI overhaul rebuilt its fishing-detection and vessel-classification models, cutting false positives.
- Detection is not enforcement: its output is “apparent fishing effort,” an estimate to check against other sources before any legal conclusion.
What Global Fishing Watch does
Global Fishing Watch is an international non-governmental organization that seeks to advance ocean governance through transparency about human activity at sea. Its public map, launched in 2016, was the first open-access online tool for visualizing vessel-based activity across the world’s oceans. It merges automatic identification system (AIS) broadcasts, vessel monitoring system (VMS) data shared by partner countries, satellite radar imagery, and night-light vessel detection, showing apparent fishing activity, vessel presence, port visits, and encounters between vessels, with data from 2012 to the present. It covers nearly 70,000 commercial fishing vessels that broadcast on AIS — but only the share of the fleet that broadcasts at all.
How analysts use it to find dark vessels
A “dark vessel” is an industrial fishing vessel that does not publicly broadcast its position through AIS and is not covered by a government VMS feed shared with Global Fishing Watch. Analysts find them by matching radar detections from the European Space Agency’s Sentinel-1 satellites against known AIS positions; detections with no matching broadcast become candidate dark vessels, which machine learning then classifies as fishing or non-fishing.
The scale of the gap was established by a study published in Nature in January 2024 and led by Global Fishing Watch researchers. Combining five years of Sentinel-1 radar and Sentinel-2 optical imagery with GPS data from 2017 to 2021 — two petabytes of imagery, 67 million image tiles, and 53 billion AIS positions — the team found that 72 to 76 percent of the world’s industrial fishing vessels were not publicly tracked, with dark activity densest around Africa and South Asia and dark vessels found inside many marine protected areas. Analysts corroborate map findings against vessel registries, port visits, and encounters with refrigerated cargo vessels that can indicate transshipment at sea. WarBrief’s profiles of MarineTraffic and TankerTrackers cover the complementary AIS and sanctions-tracking side of this workflow; Global Fishing Watch adds the satellite layer AIS alone cannot see.
The freshest reason to revisit the tool is its October 21, 2026 upgrade, the first major structural update to its core AI models since the organization was established. The new fishing-detection model was trained on more than 1,000 expert-reviewed examples, adds more than 5,300 anchorages across 13 countries, and applies a unified spatial grid and higher-resolution bathymetry. The practical gain is fewer false positives: gear and drifting buoys, and vessels slowing near port approaches, were previously misclassified as fishing. Users may therefore see lower apparent fishing estimates in some areas — a correction of past overcounting, not evidence that fishing declined.
Access and pricing
The public map is free to anyone with an internet connection, with no subscription fee. Global Fishing Watch also publishes APIs, an R package (gfwr), a Python client, and a data download portal, all free for non-commercial use through self-registration; its APIs are used by more than 200 organizations across nearly 70 countries, and near-real-time data carries roughly a three-day delay. For commercial use there are no public license prices: standard terms do not cover commercial products, and custom licenses are considered only in clearly mission-aligned cases.
Limitations analysts should know
First, detection is not enforcement: the output is “apparent fishing effort,” and Global Fishing Watch recommends it be used alongside official registries, local intelligence, and original tracking information before any definitive legal or regulatory conclusion. Second, no model can fill an AIS gap it cannot see: the October 2026 upgrade improves analysis of the broadcast fraction of the fleet but does not change the 72 to 76 percent dark figure, and satellite radar coverage is periodic rather than continuous. Third, VMS coverage depends on partner governments sharing data. Absence from the map means “not observed,” never proof a vessel was not there.
Tool Q&A
What does this map show?
Apparent fishing activity, vessel presence, port visits, and vessel-to-vessel encounters, from AIS broadcasts, partner VMS feeds, satellite radar, and night-light detection.
How often does it update?
Near-real-time data with roughly a three-day delay, with a historical record from 2012 to the present.
Where does the data come from?
AIS broadcasts, VMS data shared by partner countries, Copernicus Sentinel-1 radar and Sentinel-2 optical imagery, and night-light detection, processed by machine-learning models.
Frequently asked questions
Is Global Fishing Watch free?
Yes. The map, APIs, data packages, and code are free for non-commercial use, including research, NGOs, journalists, and governments publishing free and open tools. Commercial use requires a custom license.
What is a dark vessel?
A vessel that does not publicly broadcast its position through AIS and is not covered by a partner government monitoring feed — invisible to public tracking until satellite radar catches it.
Can Global Fishing Watch prove illegal fishing?
No. It shows apparent fishing effort, a behavioral estimate. Proving illegality requires corroboration: vessel identity, location against closed areas, registries, and official enforcement records.
Sources
- Global Fishing Watch: Global Fishing Watch launches major data upgrade for clearer picture of global fishing activity
- Tech Times: Global Fishing Watch Launches First AI Model Overhaul: 75% of Fleet Still Dark
- Earth.com: Earth’s oceans are filled with what scientists call ‘dark vessels’
- Global Fishing Watch: Can I use Global Fishing Watch APIs for commercial purposes?
More in this series: browse all of WarBrief’s intelligence tool profiles.
