Groundbreaking Study Maps Global Fishing Patterns

Image Courtesy of Stuart Price / AU-UN IST

Dylan Goldman
Staff Writer

Scientists at the Bren School of Environmental Science and Management recently published a first-of-its-kind study about their four-year project that tracked most large commercial fishing vessels in the world on a real time map.

Fishing activity now covers about 55 percent of all the oceans in the world, and it is tracked at an advanced level. The study tapped into the technology of distress beacons previously required on most large fishing vessels to map the patterns and activity of those ships. The scientists were able to use machine learning technology specifically a neural network to process the two billion transmitted signals they received.

Juan Mayorga, a first year Masters student, Fellow of Latin American Fisheries at UCSB’s Bren School of Environmental Science and Management, and co-author of the study, weighed in on the study’s process in an interview with The Bottom Line.

“What [the models] do is they learn and infer fishing activity versus transiting behavior based on the behavior of the vessel. So how fast it’s moving, how often it’s changing its course, what are the patterns. Fishing vessels have carried the same patterns of movement across different years,” Mayorga said.

“So someone fishing for tuna … has a very distinct loop pattern of movement, whereas vessels fishing with long lines would have more of a zigzag kind of pattern of movement.”

Mayorga also explained that the value of the study goes beyond the advancement of science and the general knowledge of global fishing activity. Governments can analyze the data to see the potential effect of fishing policy on the actual market. If a government enacted a policy that would decrease fishing subsidies, for example, they could now analyze data from this study and determine the difference in movements of the major fishing vessels, helping them to understand the effectiveness of that policy.

Before Professor Chris Costello and Mayorga published the study, there was no real way to know how many fishing boats there are in the oceans. For Mayorga, the project fulfilled a desire to find some information on a topic that the scientific community had virtually no statistics on.

The project was started four years ago by SkyTruth, an organization dedicated to remote monitoring of the earth, who partnered with Google and Oceana, an international advocacy organization that focuses on ocean conservation, to advance the technology used to monitor the oceans. The organization Global Fishing Watch was created from the partnership to determine if people can use already-existing technology to monitor fishing activity across the earth.

Global Fishing Watch is now completely separate from Google and Oceania. Mayorga and the other scientists involved began the project when it was started by SkyTruth, but have continued working on it until now, when it is ran solely through Global Fishing Watch.

“There was a need to re-advance our monitoring of the oceans; forestry, fishing, agriculture, they’re all the main ways that we alter global ecosystems,” Mayorga said. “Fishery has always lagged behind — the technology just wasn’t there yet.”

Although revolutionary in its unique ability to track fishing vessels in real time like never before, the model in this study can only see large fishing vessels, and only if they have the distress beacon that sends out the signal to satellites. Whether or not the system will pick up the vessel depends on individual countries’ regulations of whether or not they require vessels to carry the AIS beacon.

“One of the limitations of the study is that we don’t have all the vessels in the world,” said Mayorga about the future of the technology and where the project is headed. “One of our next steps is to start incorporating other sorts of technology that would allow us to see more vessels. So, for example, radar or satellite imagery or other types of monitoring systems that are found in smaller vessels.”