Squid fishing could be getting out of control due to the industry’s lack of regulations, scientists say, prompting calls for greater oversight.

Thousands of squid fishing vessels operate across the world, using light to lure the eight-armed cephalopods to the surface and catching them with nets or jigging equipment. While some research suggests that squid are globally abundant, other evidence suggests that overfishing is driving some populations to decline, including the jumbo flying squid (Dosidicus gigas) in the Southeast Pacific and the Argentine shortfin (Illex argentinus) in the Southwest Atlantic. Experts also say that most squid fishing takes place in unregulated areas in international waters, which has allowed the industry to operate without scrutiny.

In a new study published in Science Advances, researchers from Global Fishing Watch, the University of California, Santa Cruz, the Australian National Centre for Ocean Resources and Security at the University of Wollongong, and the Japan Fisheries Research and Education Agency used satellite and vessel tracking data to study the movements of the squid fishing vessels. It found that squid fishing across the global oceans increased by 68% over three years (2017-2020), accounting for about 4.4 million total hours of fishing time. The study also indicated that 86% of this fishing occurred in unregulated areas, and that many of the vessels traveled long distances to operate in different regions.

The authors say it can also exacerbate inequity for traditional and small-scale fishers in developing coastal states that depend on fishing revenue. That’s because large industrial squid fleets often fish in unregulated areas that directly border coastal states’ exclusive economic zones (EEZs), outcompeting the smaller fisheries for the same stock.