Are Chinese 'dark fleets' illegally defying sanctions by fishing in North Korean waters?

Using satellite imagery, a new study has tracked more than 900 Chinese fishing vessels operating in North Korean 'exclusive economic zone', where any international fishing inside its borders is a violation of international law.

Fishing vessels in front of Xiamen, China
Fishing vessels in front of Xiamen, China. Image:, CC BY-SA 2.0

Chinese “dark fleets” illegally fished a $440 million haul of the squid species Todarodes pacificus in North Korean waters during 2017 and 2018, according to a study published today in the journal Science Advances.

The study used a novel set of satellite images to track fishing vessels operating off the northeast coast of the Korean peninsula, including satellite synthetic aperture radar (SAR), Visible Infrared Imaging Radiometer Suite sensors (VIIRS), high-resolution optical imagery, and identification beacon data from some of the vessels themselves. Its authors say that this is one of the first times those technologies have been combined to map illicit fishing at such a large scale over a years-long period.

“We believe that this study marks the beginning of a new era in fisheries management, transparency, and monitoring,” said Jaeyoon Park, senior data scientist at Global Fishing Watch and a co-lead author of the paper.

Park and his colleagues used data collected from Planet Labs, an earth-imaging company that has also been instrumental in tracking deforestation caused by hard-to-track illegal gold mining, to map the movement of fishing boats in contested waters around the Korean peninsula. They found that in 2017, more than 900 Chinese fishing boats traveled to an area in the North Korean ‘exclusive economic zone,’ followed by another 700 in 2018.

In total, researchers estimate that the vessels caught more than 160,000 tonnes of Pacific flying squid in those two years alone, worth hundreds of millions of dollars.

Tracking squid harvests in those waters has been challenging due to a dispute over where ocean borders in the region begin and end, with Russia, Japan, China, and North and South Korea each making their own claims. As a result, cooperation in monitoring and sustainably managing stocks of fish, squid, and other ocean wildlife has been complicated by big-power politics.

If the fishing was conducted without permission of the central government of China, it represents a violation of China’s distant water fishing management regulation, which requires all Chinese flagged vessels to obtain permission to fish in other nation’s borders.

Jaeyoon Park, senior data scientist, Global Fishing Watch

Pacific flying squid is a staple food in the region and a key source of income for fishing communities in Japan and the Korean peninsula, but in recent years catch volumes have plummeted, raising fears that the lack of coordination is depleting stocks and facilitating illegal fishing. According to the study, since 2003 squid catches have dropped by 80 per cent in South Korean waters and 82 per cent in those of Japan.

“Illegal fishing in these waters is a very serious matter in Japan, and the lack of shared data and management is a major challenge considering the critical importance of squid in the region,” said Masanori Miyahara, President of the Japan Fisheries Research and Education Agency, in a press release that accompanied the study.

Complicating matters are economic sanctions that were imposed on North Korea by the UN Security Council in late 2017 in response to the nation’s ballistic missile tests. The presence of Chinese fishing vessels in North Korean waters would represent a violation of those sanctions and an embarrassment to the Chinese government, which has issued public assurances that it would not allow ships flying its flag to fish in those waters.

“If the fishing was conducted without permission of the central government of China, it represents a violation of China’s distant water fishing management regulation, which requires all Chinese flagged vessels to obtain permission to fish in other nation’s borders,” said Park.

Park says the satellite data doesn’t reveal whether the North Korean government has given permission for the vessels to fish inside its borders, but adds that South Korean coastal officials have found evidence suggesting that North Korea is aware that it is taking place.

“There are some indications from the South Korean authorities that when they inspect some of these vessels traveling to North Korean waters, some carry documents that appear to be issued by [North Korean] authorities,” he said.

The presence of Chinese “dark fleets” off the coast of North Korea is also causing a crisis for North Koreans who rely on squid fishing for their livelihood. Unable to compete with the more technologically advanced Chinese vessels, which use powerful lights and other technologies to maximize the size of their catch, some North Koreans have resorted to fishing illegally in faraway Russian waters – a potentially deadly journey for their smaller wooden ships. The study found that 3,000 North Korean ships fished in Russian waters in 2018 alone.

In recent years, hundreds of North Korean fishing vessels have washed ashore in neighboring countries. The shipwrecks baffled many observers and provoked questions of potential espionage. But the study’s authors say that their data reveals a more straightforward answer: after being pushed out of local waters by the Chinese vessels, North Korean fishermen are taking life-threatening risks to fish in more remote areas, often paying a heavy price.

This phenomenon has led to some fishing villages in North Korea becoming colloquially known as “widow’s villages.”

Park says he hopes the data gathered by researchers and published in the study will lead to greater regional cooperation and a political solution to illegal fishing:

“We really urge that this is time to accelerate data sharing processes in the region, and also to negotiate a way to deal with regional fishing management mechanisms given the importance of those fisheries and the number of people who rely on those resources for their livelihoods.”

This story was published with permission from

Did you find this article useful? Join the EB Circle!

Your support helps keep our journalism independent and our content free for everyone to read. Join our community here.

Most popular

Featured Events

Publish your event
leaf background pattern

Transforming Innovation for Sustainability Join the Ecosystem →