"Ghost ships" carrying the bodies—or skeletons—of North Korean fishermen have been washing up in Japan for years, but there was a massive increase after 2017. A new study links the rise to "dark fishing fleets" of Chinese vessels in North Korean waters in violation of United Nations sanctions in 2017, CNN reports. Pyongyang apparently sold the rights to fish in its waters to recoup income it lost under sanctions, a move that forced the country's own fishing vessels to fish for squid illegally in distant Russian or Japanese waters. When the ill-equipped wooden boats ran out of fuel or had engine trouble, they ended up being carried to the shores of Japan, researchers say. They say the death toll has been so high that some settlements on North Korea's east coast have become "widows' villages."
The researchers used satellite data to determine that more than 900 Chinese vessels fished illegally in North Korean waters in 2017 and more than 700 did so the following year, the Guardian reports. "It is the largest known case of illegal fishing perpetrated by vessels originating from one country operating in another nation's waters," says Jaeyoon Park, co-author of the study from the Global Fishing Watch nonprofit. Over the last five years, around 600 "ghost ships" have washed up in Japan, including more than 150 last year. The researchers say that beyond the human toll, the industrial Chinese trawlers have rapidly depleted fish stocks. Stocks of Pacific flying squid in Korean and Japanese waters are down by more than 80% since 2003, which experts say is at least partly due to overfishing. (Read more North Korea stories.)