A tuna fishing boat drags a cage of nets on the Mediterranean. (Photo: Andreas Solaro/AFP/Getty Images)

Attention, fishing boats on the high seas, Big Brother is watching—and now he has night vision.

For the last few years, the non-profit Global Fishing Watch has tracked the movements of fishing vessels by using satellites and ship-based automated identification systems (AIS) to shed light on illegal and unreported fishing and monitor commercial fleet activities. Just last week, for example, researchers reported using the data to estimate profits brought in by vessels fishing international waters.

But the group hasn't been able to track all vessels, and neither have government officials. One challenge is that not all boats are required to use AIS. Others are, but may turn off the devices to intentionally avoid detection. That is now changing, however, as Global Fishing Watch expands its ability to tap new kinds of data.

"The vessels that are being compliant and have their transmitters on, we can see them already," said Tony Long, Global Fishing Watch's chief executive. "There are a lot more vessels on the water that we can't see because they don't have their tracking systems turned on."

Last week, the organization announced it is turning to a new imaging system capable of filling in a major data gap: vessels that fish at night. Each night, Global Fishing Watch said, its new nighttime surveillance system is detecting 10,000 to 20,000 boats, or 85 percent of total vessels, that aren't transmitting location signals. In addition, the organization is also releasing what it says is the first-ever live global view of open ocean transshipment, a practice in which boats rendezvous to transfer goods from one to another.

Both practices—nighttime fishing and transshipment—don't indicate anything illegal is occurring, but to watchdogs and regulators such activities can be red flags for illicit goings-on. That information could also simply help governments simply better estimate how many fish are being pulled out of the sea and identify previously unknown fishing grounds.

"Coastal states need to be aware that there is a percentage more vessels fishing in their waters than they seem to have authorized," Long said.

The London-based Global Fishing Watch was launched in 2015 through a collaboration with Oceana, Google, and SkyTruth. It tracks data from existing monitoring systems and then analyzes movement patterns of vessels to identify ones that are fishing, as opposed to, say, shipping cargo. In some cases, it can determine what species a boat is likely fishing for or with what gear. If a vessel's tracking system shuts off for long periods of time, the software may flag it.

The nighttime fishing data is just one way the group is now expanding its surveillance abilities. Initially, Global Fishing Watch used only tracking data from AIS—a technology first widely implemented primarily as a means of helping mariners avoid collisions. Now, the group is pushing to incorporate a second layer of information from vessel monitoring systems, or VMS, installed on many boats to send data to government regulators.

While the large majority of governments don't make VMS data public, that is changing. Indonesia recently agreed to provide the information for Global Fishing Watch, adding the movements of 5,000 fishing vessels to the organization's database. Other nations, Long said, are planning to do the same.

Meanwhile, a company based in San Francisco called Pelagic Data Systems has developed lightweight solar-powered transmitters designed for placement on small boats that may be unable to run other more cumbersome AIS and VMS tracking systems that require either onboard power or large batteries. This system and other advances in tracking technology, Long said, will allow Global Fishing Watch to monitor the activity of perhaps 300,000 boats within a decade—about 75 percent of all commercial fishing boats.

The new system that detects boats fishing at night, called Visible Infrared Imaging Radiometer Suite, or VIIRS, is fixed to a National Oceanic and Atmospheric Administration satellite launched in 2011. The extremely sensitive sensors can detect vessels' lights that are used for navigation or attracting fish or squid. Some boats don't turn on any lights, making them undetectable to the new system. However, Long said that, later this year, Global Fishing Watch will also incorporate a radar system into its toolset to see even boats that have no lights or are fishing under dense cloud layers.

The VIIRS array is already revealing new information about squid fishing, which generally takes place at night using very bright floodlights that draw the animals to the surface. Global Fishing Watch and a researcher at the Peru-based branch of the non-profit organization Oceana have analyzed the new data and found that, of the 200 Chinese vessels that target squid off Peru's coast, about 20 percent were operating without broadcasting their signal—a sign they may be trying to dodge authorities.

Elliott Hazen, an assistant adjunct professor of ecology and evolutionary biology at the University of California–Santa Cruz, is using Global Fishing Watch data of where boats fish to identify areas where large ocean predators, mainly tuna and sharks, are most likely to be caught unintentionally as bycatch. He said the group's data processing programs and the new nighttime imaging system could improve enforcement of regulations aimed at minimizing harm of protected species from fishing vessels.

"If you can identify where the fish are, and where the boats are, then you can get a complete picture on bycatch risk" and establish fishing rules accordingly, he said. A boat, he said, that fishes an area known to be inhabited by a protected species but never reports any bycatch could also, in theory, be a red flag to authorities.

Loyola Marymount University instructor and biologist Demian Willette, who uses DNA sampling to investigate mislabeling of seafood, also expects Global Fishing Watch's data to strengthen authorities' ability to identify and prosecute scofflaw vessels.

He is now developing a DNA sampling tool for use by law enforcement. However, finding DNA traces of a protected species in a boat's empty fish hold, he said, might not be enough evidence to make a case that a boat was illegally fishing. The confirmation that they were fishing in the habitat of that same species, he said, adds a second layer of evidence. So could the transshipment map, if it shows a suspect boat rendezvoused with a larger boat at sea to transfer illegal catch, he said.

"Their efforts to bring more of this tracking data to the public is really the key here," Willette said.

In an email, Beth Lowell, Oceana's senior director of illegal fishing and seafood fraud, said Global Fishing Watch data already is helping authorities make busts, such as a $1 million fine paid by a company that owned the vessel Marshalls 203. The boat, she said, was shown to be fishing illegally in the island of Kiribati's Phoenix Islands Protected Area, declared off-limits to commercial activity in 2015.

As well as assisting authorities and regulators, a new era of high seas transparency could simply deter bad behavior. Fishing vessels may abide by regulations they might previously have violated, Long said, or realize turning off their trackers won't hide their behavior. Hazen said that new solar-powered trackers that could some day monitor vessels as small as a kayak would add one of the final pieces of the puzzle.

"That would help fill the gap," Hazen said. "Together, with Global Fishing Watch, that could provide the complete data set on our global fishing fleets."

This article originally appeared on Oceans Deeply, and you can find the original here. For important news about our world’s oceans, you can sign up to the Oceans Deeply email list.