According to an article published by the U.S. Southern Command, Chinese fishing vessels have aggressively violated maritime boundaries and conducted illegal fishing operations as far away as South America in older to sustain China’s massive demand for seafood. This entanglement isn’t purely economic, and comes with reverberating effects within both security and environmental circles the world over.

Addressing concerns about China’s massive fishing fleet (estimated at nearly 3,000 ships) is complicated, in large part because its activities often skirt the boundary of international waters. These vessels routinely violate the sovereign waters of other nations–often bolstered by Chinese Coast Guard escorts–but return to international waters before they can be caught and charged. From there, ship-to-ship transfers with refrigerated vessels allow the Chinese fishing industry to continue stripping other areas of marine life without acknowledging regional limits established by local governments.

It’s not that the Chinese fleet can’t fish in international waters, but its close presence generates controversy. For example, Juan Carlos Sueiro, Peru’s fisheries director of the international organization, Oceana, indicated that it “already identified vessels entering into Peruvian waters without a license or with duplicated ID.”

These violations create a complicated security environment for South American nations to prevent Chinese fishing crews from over-fishing their waters or hunting endangered or protected species. Regions near Peru and Argentina have the largest congregation of these vessels in the world. Often, there’s a lack of infrastructure for surveillance or the means to mount an effective determent effort. In August of 2017, the vessel Fu Yuan Yu Leng 999 was boarded by authorities from Ecuador after the crew was caught fishing in a protected marine reserve. Onboard, authorities found 300 tons of shark fins, which had been cut off of live sharks that were thrown back to sea. The harvest is for a specialty dish in China, shark fin soup, which is commonly served at special occasions such as weddings.