Take charge of marine vessels on the high seas.
Supervises and coordinates activities of crew aboard ship: Inspects holds of ship during loading to ensure that cargo is stowed according to specifications. Examines cargo-handling gear and lifesaving equipment and orders crew to repair or replace defective gear and equipment. Supervises crew engaged in cleaning and maintaining decks, superstructure, and bridge of ship. Stands watch during specified periods and determines geographical position of ship, upon request of MASTER, SHIP, using loran and azimuths of celestial bodies. Assumes command of ship in event MASTER, SHIP becomes incapacitated. May be required to hold license issued by U.S. Coast Guard, depending on waters navigated and tonnage of ship. When more than one MATE, SHIP is required, may be designated Mate, Chief; Mate, First; Mate, Fourth; Mate, Second; Mate, Third. May remain in port to relieve another MATE, SHIP who desires to go ashore while ship is in port and be designated Mate, Relief.