Self-localization of buoyless fishing gear and other objects on the sea floor

End lines used in commercial trap/pot fishing pose a significant entanglement risk to whales, sea turtles, and sharks. Removal of these ropes for buoyless fishing is being considered by the United States and Canadian governments, but a method to systematically locate the gear without an attached buoy is required. A method was developed for an acoustic modem to self-localize and broadcast its location to nearby ships to minimize gear conflict, optimize power consumption, and reduce lost gear. This method was implemented using a research modem that self-localized to within 5 m of its estimated location on the sea floor.