In January 2019, the Korean-flagged fishing vessel Oyang 77 sailed south toward international waters off Argentina. The vessel had a known history of nefarious activities, including underreporting its catch and illegally dumping low-value fish to make room in its hold for more lucrative catch.
At 2 a.m. on Jan. 10, the Oyang 77 turned off its location transponder at the edge of Argentina's exclusive economic zone – a political boundary that divides Argentina's national waters from international waters, or the high seas. At 9 p.m. on Jan. 11, the Oyang 77 turned its transponder back on and reappeared on the high seas. For the 19 hours when the ship was dark, no information was available about where it had gone or what it did.
