Now, a new study from a team working at Stanford is pulling back the curtain on the global fishing industry and a fleet of specialized vessels that operate out of the spotlight.
You probably know the type of seafood you like to eat, but knowing exactly where it comes from can be trickier, especially if it's taken a detour on what some researchers are calling "fish taxis." They're giant refrigerated ships that ply the world's oceans, transferring the catch from cargo holds of commercial fishing vessels, allowing them to stay out at sea for a long as possible.
"So what they allow is going out at sea and getting the cargo, bringing it back to port while the fishing vessels keep fishing. And that's the main job that they are doing," said researcher Jean-Baptiste Jouffray, Ph.D.
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Jouffray and fellow researcher Frida Bengtsson are with the Stanford Center for Ocean Solutions and the Stockholm Resilience Center in Sweden. They say tracking the refrigerated ships, also known as reefer vessels, could be key to making the ocean supply chain more transparent and spotting illegal fishing.
"So this is what we tried to change with this study, because we believe that engaging with these owners can open up new pathways for transparency around this activity," Bengtsson said.
Their study builds on a data tracking effort we first reported here on ABC7 News several years ago. That's when Stanford researchers began work on linking various satellite and transponder systems with artificial intelligence to better track fishing vessels. But there's still a missing piece of the puzzle with reefer ships.
"But what has been unknown is who actually owns them. And that's partly because the way that global shipping is organized, which is quite an intricate kind of owning structure," Bengtsson said.
The team began by cross-checking available location data against ship identification systems and worked backward, ultimately identifying 324 owners operating more than 500 reefer ships currently in use. China, Russia and Greece were among the most active countries, including a single, family-owned company.
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"Forty-six of those, it's a single family back in Greece. In China, for which also has a large fleet of 34, you're going to have a different pattern with many different owners owning different reefers and a lot of those companies will be state-owned eventually, because that's something you often see in Chinese industry," Jouffray said.
The new study includes an interactive map that allows the public to track whose vessels are where. The team is hoping to work with the owners to develop a stronger monitoring system and discourage illegal activity and overfishing.
"So when you buy a fish, you can actually figure out where it's been cut and where it's been fished," he said.
It helps combine the power of advanced technology with public awareness to build a healthier ocean.