The Bering Sea and its surrounding areas, the North Atlantic, and the Barents Sea have another thing in common besides being part of the Arctic: they are enormously rich in fish and therefore economically important. But fisheries have been struggling with a huge problem for decades, illegal, unregulated and unreported fishing. A study has now looked at which countries and which types of fisheries are likely to be the main culprits and found some surprising results.
When it comes to the question of belonging, the U.S., along with Taiwan on the one hand and China on the other, show huge differences. But the three countries share another commonality: their fishing fleets most often turn off their identification systems on the high seas, obscuring their position. This potentially suggests that they are involved in illegal, unregulated and unreported, or IUU, fishing activities. That’s one of the findings of a study by Heather Welch, a spatial ecologist at the Institute of Marine Sciences at the University of California Santa Cruz, and her colleagues. Other results of the work identified the type of fishery and geographic distribution of the most common locations where AIS is turned off. The team published the study in the journal Science Advances two weeks ago.
More than 3.7 billion AIS signals between 2017 and 2019 were analyzed by the researchers for their study. They obtained the data from the Global Fishing Watch AIS Data Set, in which the positions of the vessels are determined by means of the Automatic Identification System located on board. These systems are installed on most ships to provide rapid positioning and information about the ship in emergency situations. For their work, the team focused on signals that were at least 50 nautical miles from shore and came from areas where adequate signal reception is detectable. They modeled this data and whenever a signal could not be detected for more than 12 hours, a deliberate shutdown of the system was suspected. For example, the team discovered that the ships masked about six percent of their activity in specific regions by having their AIS turned off.
The team was able to show that 82 percent of the ships that had their AIS turned off belonged to China, Taiwan, Spain and the United States. Further analysis of the data also showed that the main areas affected by IUU fishing include the Northwest Pacific region and the Bering Sea, which is somewhat of a surprise. According to the results, in the Bering Sea, the U.S. is the main one to turn off its AIS. Other areas such as West Africa and the South Atlantic outside Argentina’s EEZ exclusive economic zone were already known. The types of fisheries identified by the authors of the study reflect the methods widely used in the regions, namely longline fishing, squid and tuna hunting, and trolling.
The results of the study are interesting, but the author Heather Welch also warns against judging too quickly. “There are numerous reasons why ships turn off their AIS, such as in areas where pirates are a threat or they are trying to keep fishing competitors out of the area,” she explains. While the study also considered these issues, it was able to identify locations where the AIS shutdown could have been done with potential malicious intent. But actually illegal fishing also does not show. Another aspect related to countries is the fact that AIS is most prevalent on ships from middle- and high-income countries. “AIS is not feasible for many countries in the world right now,” explains Claire Collins, who was not involved in the study, of the Zoological Society of London. As a result, poorer countries fall through the labor cracks. Still, organizations that oppose IUU fishing welcome the study.
IUU fishing is a huge problem for both the global economy and ecologists. Economically, it causes up to $25 billion in damage per year. But the ecological damage can hardly be quantified, because the illegal activities often extend into sensitive regions, where the often old, poorly maintained ships with poorly paid fishermen on board catch everything that is not nailed down, sometimes under life-threatening conditions. In Alaska, some experts blame illegal fishing for the disappearance of snow crabs. However, responsible agencies reject this accusation and refer to the strict controls. In Antarctica, too, vessels have repeatedly been caught fishing illegally. Although attempts are being made to manage the situation by carrying out stronger and more frequent controls to enforce stricter catch quotas, the situation is not being addressed. But in the end, illegal fishing iceboats can rely on one thing: The polar regions are remote and vast, and anyone who wants to hide there can do so relatively easily by flipping a switch.
Dr Michael Wenger, PolarJournal
Contributed image: (C) Interpol
Link to study: Welch et al (2022) Sci Adv 8(44) Hot spots of unseeing fishing vessels; DOI: 10.1126/sciadv.abq2109.
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