Direct courses and speeds of ships, based on specialized knowledge of local winds, weather, water depths, tides, currents, and hazards.

Prevent ships under navigational control from engaging in unsafe operations.

Serve as a vessel's docking master upon arrival at a port or at a berth.

Consult maps, charts, weather reports, or navigation equipment to determine and direct ship movements.

Steer and operate vessels, using radios, depth finders, radars, lights, buoys, or lighthouses.

Operate ship-to-shore radios to exchange information needed for ship operations.

Dock or undock vessels, sometimes maneuvering through narrow spaces, such as locks.

Stand watches on vessels during specified periods while vessels are under way.

Inspect vessels to ensure efficient and safe operation of vessels and equipment and conformance to regulations.

Read gauges to verify sufficient levels of hydraulic fluid, air pressure, or oxygen.