Tracking The World’s Boats By Satellite, To Catch Illegal Fishing From Space

Global Fishing Watch lets watchdogs know when boats aren’t where they’re allowed to be–and lets fishing companies that pride themselves on sustainability verify their legal catches.


Black-market fish–caught illegally, or unreported or unregulated–make up as much as a third of the fish sold in the world. But catching pirate fishermen among the tens of thousands of fishing boats in world is not an easy problem to solve.


Now, like activists tracking forests and factory farms, ocean nonprofits and governments are increasingly turning to satellites and algorithms to find violations.

Global Fishing Watch, a tool launched publicly on September 15, maps out broadcast data that tracks ships using satellites. The tool can track the path of ships over time, and identify suspicious patterns that indicate either overfishing or illegal fishing.

“We can set good policies, but if they’re not being followed, they don’t work,” says Jacqueline Savitz, vice president for U.S. oceans at the nonprofit Oceana, which partnered with Google and the nonprofit SkyTruth on the tool. “So we also need to address that problem. Global Fishing Watch is a way to try to shed light on the amount of fishing that’s happening, and the type of fishing and whether or not fishing is following the rules.”

Oceana has used satellite data for years, but in the past, analysis happened manually, watching the path of a ship in real time to determine whether it might be fishing illegally.

A fishery analyst “would have to wait by the computer to plot a data point of where the vessel was, and then she would wait again and plot the next data point of where the vessel now was two or four hours later,” says Savitz. “And do that over long periods of time and develop a pattern of where is this vessel and is it fishing.”


The process could take months, and that was only for a single boat. The new system can automatically analyze all 35,000 large commercial boats that use the Automatic Identification System (AIS), which tracks boats from satellites and land-based receivers. Using algorithms, it can identify suspicious patterns.

At the most basic level, it’s possible to see if a boat is fishing in an area that’s closed to fishing. But a government could also easily look at boats in a country’s exclusive economic zone, an area with restricted fishing, and identify vessels that aren’t allowed. It’s also possible to look for behaviors that suggest a boat might be using slave labor onboard.

“We can see when boats turn off their AIS devices, probably because they don’t want to be seen,” says Savitz. “We can see when a vessel sneaks out of a certain area where it was fishing just briefly and then comes back, which could be considered suspicious behavior. It’s possible that the vessel is offloading its fish so that it can avoid scrutiny when it comes into port, maybe not have to report its catch.”

While the organization is helping governments use the tool, it also made it available publicly so others could pressure governments to enforce more. Oceana hopes that journalists, watchdog groups, and even other fishermen will start to use it.

The tool only tracks boats using AIS, but that tends to include the industrial-scale fishing vessels most likely to cause problems. Now some smaller fishing boats also want to start tracking their own movements–so they can prove they’re fishing sustainably.


In a pilot project with an Indonesian company called Bali Seafood, which put 100 data trackers on small boats, Oceana is using the system to show that those boats fished where they claimed to.

“What they want to do is use that in a positive to say to the seafood buyers, ‘buy seafood that you can track all the way back to the boat where it was caught,'” Savitz says. “That will give them hopefully some sort of a marketing advantage.”

Oceana is also working with Trace Register, a company that helps retailers like Whole Foods certify seafood as “traceable.” It’s one attempt–like tracking fish on the blockchain–to help solve the problem of massive seafood fraud. Trace Register already tracks fish, but the new tool can verify that path.

“They’re not only providing traceability and saying that ‘they told me this fish was caught in the Indian Ocean on September 12,’ but they’ll verify whether or not the vessel was really in that location using Global Fishing Watch,” she says. “It’s not just traceable seafood, but verified traceable seafood.”

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About the author

Adele Peters is a staff writer at Fast Company who focuses on solutions to some of the world's largest problems, from climate change to homelessness. Previously, she worked with GOOD, BioLite, and the Sustainable Products and Solutions program at UC Berkeley, and contributed to the second edition of the bestselling book "Worldchanging: A User's Guide for the 21st Century."