Global map shows where fishing vessels turn off their detection devices – sometimes to illegal activity

This map shows the estimated total fishing vessel activity and the amount of this activity obscured by the suspected disabling of the automatic detection system in areas with sufficient satellite reception. Areas with the highest fishing vessel activity and the highest degree of unexplained activity occur in three areas of concern for illegal, unreported and unregulated fishing: near Argentina and West Africa, and in the Pacific Northwest. In contrast, fisheries in the waters near Alaska are some of the most intensively managed in the world. credit: Global Fishing Watch

A new dataset of intentionally disabling automatic detection system devices by fishing vessels provides insight into illegal, unreported and unregulated fishing activity.

To avoid collisions with other ships, many ships are equipped with Automatic Identification Systems (AIS). It was created as a collision avoidance device and provides information such as the position, course and speed of nearby ships to complement maritime radar. However, data from shipboard AIS can also provide information about global fishing activity, including illegal, unreported and unregulated fishing. Fishing vessels can disable their AIS equipment. A new data analysis identifies intentional disabling incidents in commercial fisheries and shows that, while some disabling incidents may occur for legitimate reasons, others appear to be attempts to hide illegal activities.

This new study presents the first global dataset of disabling AIS in commercial fisheries, which obscures vessel activity by up to 6%. It was published on November 2 in the journal science advance,

First author Heather Welch, a project scientist in Marine Science Institute Worked on the study with researchers at the University of California, Santa Cruz (UC Santa Cruz) global fishing watch, which maintains the AIS dataset of vessel activity and NOAA fisheries. After Global Fishing Watch developed a way to intentionally disable it from gaps in satellite coverage and other technical issues, Welch used a machine learning method To identify the four primary reasons for disabling AIS.

“There are some valid reasons why ships disable their AIS, but we found two situations in which it is done for potentially nefarious reasons, either fishing in unauthorized locations or to obscure unauthorized transshipment,” she said. “This dataset is now operational, and the data is generated in real time, so it can be used to target inspections and improve fisheries management.”

For the study, researchers identified more than 55,000 suspected intentional disabling incidents between 2017 and 2019 that obscured nearly 5 million hours of fishing vessel activity. Suspected AIS disabling unexplained over 40% of the total hours occurred in four hotspots, three of which are areas of concern for illegal fishing: the Pacific Northwest and adjacent to the Exclusive Economic Zones (EEZs) of Argentina and West African countries. region. These areas have rich fishing grounds with limited management oversight.

“AIS data can tell us a lot, but it can also be lacking,” said co-author Tyler Clawell, data scientist for Global Fishing Watch. “We may not always be able to see what ships are doing, but knowing that they are deliberately concealing their movements provides valuable information that managers and scientists did not have before. Having a better understanding of what is hiding allows officials to deploy more strategically valuable water resources, supporting better fisheries management.

Incidents of disabling were concentrated in waters adjacent to EEZ boundaries, suggesting that ships may disable AIS before entering unauthorized locations for illegal fishing. Welch said that in many cases, ships go dark as they approach the edge of the EEZ where they are not authorized to fish. “For example, you can see a Korean-flagged ship heading towards Argentina, and then it goes dark in international waters outside Argentina’s EEZ,” she said.

In particular, disabling was particularly common with overlapping claims within and around the EEZ, such as the Falklands/Malvinas Islands which are disputed by the UK and Argentina. Political conflicts in these areas can create blind spots for enforcement.

Incidents of disabling were also common in areas with high transshipment activity, where boats transfer their catches to refrigerated cargo ships. Transshipment can be an efficient way to get a ship back to shore and resume fishing quickly, but it can also be used to obscure illegal fishing activity, effectively a cargo vessel. through “laundering” illegal catch. In addition, it could enable forced labor on fishing boats that never go to ports.

The study also found evidence that ships engaged in legal activities do some incapacitation for legitimate reasons. In some cases, Welch said, AIS can be disabled to hide the locations of good fishing grounds from competitors. The fourth disabling hotspot was caused by the disabling of US trawlers in US waters off the coast of Alaska. “It is one of the most intensively managed fishing grounds in the world, and these incidents are likely a hiding place from competitors,” she said.

Another valid reason to disable AIS is piracy protection. “Using the historical attacks database, we can see that ships have set off AIS in these historically dangerous waters, and this may be because pirates have not been able to track and intercept them,” Welch said.

The approach demonstrated in this study can be used to support surveillance and enforcement efforts.

“This new dataset is an untapped resource that provides a real opportunity to trace previously observed behavior and illegal fishing activities,” Welch said. “Officers can use this information to decide where to send surveillance drones or patrol vessels, and it can also be used to focus port inspections on vessels that have entered or near EEZ borders. AIS has been disabled in the transshipment hotspot.”

References: Heather Welch, Tyler Clawell, Timothy D. White, Megan A. Cimino, Jennifer van Osdale, Timothy Hochberg, David Crudsma and Elliot L. “Hot Spot of Unseen Fishing Vessels”, 2 November 2022, by Hazen science advance,
DOI: 10.1126/sciadv.abq2109

In addition to Welch and Clavel, co-authors of the paper include Timothy White, Jennifer van Osdale, Timothy Hochberg and David Crudsma at Global Fishing Watch; Megan Cimino, an assistant researcher at the Institute of Marine Sciences and an adjunct assistant professor of ocean science at UCSC; and Elliot Hazen, an assistant professor of ecology and evolutionary biology at UCSC. Welch, Cimino and Hazen are also affiliated with NOAA Southwest Fisheries Science Center, UCSC/NOAA fisheries partner program Supports collaboration between UCSC and NOAA Fisheries.

This work was funded by the Catena Foundation and NOAA’s Office of Law Enforcement.