Water transportation workers—known on commercial ships asmerchant mariners—perform services that help provide mass local and international cargo and passenger transportation. Merchant mariners operate and maintain numerous types of watercraft, including tugboats, dredges, towboats, ferries, deep-sea merchant ships and excursion vessels. These vessels provide transportation services on rivers, canals, the Great Lakes, Oceans, within harbors and on other bodies of water.
Ships and water vessels on both domestic and international bodies of water are supervised or commanded by pilots, captainsand mates. The chief commanderand supervisor of a water vessel’s crew and operations are called a captain or master. A captain or master decides on the appropriate course and velocity for their vessel. They also monitortheir craft’s position using navigational charts and instruments, and maneuver the ship to avoid potential hazards. Captains supervise crew members who perform basic operational tasks, which include steering the vessel, operating its engines, determining its location,performing maintenance, handling lines, operating equipment and communicating with other vessels. With the assistance of department heads, captains ensure the safe and proper operation of the vessel; verify the proper working order of equipment and machinery, and direct passenger and cargo loading procedures. In addition to these tasks, captains and department heads keep careful records of their ship’s movements, the cargo and passengers transported and efforts taken to control pollution.
Routine vessel operations are directed by deck officers or mates, who stand watch for defined periods that are typically 4 hours on and 8 hours off. In the case of some small vessels that have only one mate, the captain and the mate (sometimescalled a pilot) alternate watches. If the captain becomes incapacitated, the mate takes full command of the vessel. On ships that operate with more than one mate, different mates are referred to as first (or chief) mate, second mate, third mate and so forth. Mates help direct the crew’s activities, such as maintenance and upkeep operations. Mates also ensure proper loading procedures by inspecting cargo holds during loading.
Pilots are responsible for steeringships through confined waterways, such as harbors, rivers and through straits. In such areas, pilots provide vital knowledge of local water conditions, including depths, currents, wind, tides and hazards, such as shoals and reefs. On river and canal watercrafts, pilots—like mates—are generally regular crew members. Harbor pilots normally work on an independent contract basis, often guiding numerous ships each day as theyenter and exit port. Motorboat operators transport small groupsof people (6 or less) on fishing charters. They operate small, motor-powered watercrafts. Motorboat operators also perform other tasks, such as taking depth soundings in turning basins and providing liaison services between ships, ships and shores, harbors and beaches or on area patrol.
Watercraft machinery such as pumps, boilers, generators and engines are maintained, repairedand operated by ship engineers. Most merchant marine vessels employ a chief engineer along with three assistant engineers, whose job it is to stand periodic watches to monitor the safety of engine and machinery operations.
Under the supervision of the ship’s engineering officers, marine oilers and more experienced qualified members of the engine department (QMEDs), work in the engine spaces below deck to maintain the craft’s proper running order. This work involves lubricating thenumerous moving parts of the engines and motors, including bearings, gears and shafts. Marine oilers and QMEDs also read temperature and pressure gauges, record data and occasionally help with machinery repairs and adjustments.