Command vessels in oceans, bays, lakes, rivers, and coastal waters.

Interview and hire crew members. Maintain boats and equipment on board, such as engines, winches, navigational systems , fire extinguishers, and life preservers. Measure depths of water, using depth-measuring equipment. Purchase supplies and equipment. Read gauges to verify sufficient levels of hydraulic fluid, air pressure, and oxygen. Resolve questions or problems with customs officials. Signal passing vessels, using whistles, flashing lights, flags, and radios. Tow and maneuver barges, or signal tugboats to tow barges to destinations. Contact buyers to sell cargo such as fish. Perform various marine duties such as checking for oil spills or other pollutants around ports and harbors, and patrolling beaches. Sort logs, form log booms, and salvage lost logs. Calculate sightings of land, using electronic sounding devices, and following contour lines on charts. Compute positions, set courses, and determine speeds, by using charts, area plotting sheets, compasses, sextants, and knowledge of local conditions. Direct and coordinate crew members or workers performing activities such as loading and unloading cargo, steering vessels, operating engines, and operating, maintaining, and repairing ship equipment. Inspect vessels to ensure efficient and safe operation of vessels and equipment, and conformance to regulations. Maintain records of daily activities, personnel reports, ship positions and movements, ports of call, weather and sea conditions, pollution control efforts, and/or cargo and passenger status. Monitor the loading and discharging of cargo or passengers. Signal crew members or deckhands to rig tow lines, open or close gates and ramps, and pull guard chains across entries. Steer and operate vessels, using radios, depth finders, radars, lights, buoys, and lighthouses. Arrange for ships to be fueled, restocked with supplies, and/or repaired. Assign watches and living quarters to crew members. Collect fares from customers, or signal ferryboat helpers to collect fares.

Transportation -- Knowledge of principles and methods for moving people or goods by air, rail, sea, or road, including the relative costs and benefits. Geography -- Knowledge of principles and methods for describing the features of land, sea, and air masses, including their physical characteristics, locations, interrelationships, and distribution of plant, animal, and human life. Mathematics -- Knowledge of arithmetic, algebra, geometry, calculus, statistics, and their applications . Administration and Management -- Knowledge of business and management principles involved in strategic planning, resource allocation, human resources modeling, leadership technique, production methods, and coordination of people and resources.

Operation and Control -- Controlling operations of equipment or systems. Operation Monitoring -- Watching gauges, dials, or other indicators to make sure a machine is working properly. Coordination -- Adjusting actions in relation to others' actions. Management of Personnel Resources -- Motivating, developing, and directing people as they work, identifying the best people for the job. Speaking -- Talking to others to convey information effectively. Judgment and Decision Making -- Considering the relative costs and benefits of potential actions to choose the most appropriate one. Mathematics -- Using mathematics to solve problems. Active Listening -- Giving full attention to what other people are saying, taking time to understand the points being made, asking questions as appropriate, and not interrupting at inappropriate times.

Spatial Orientation -- The ability to know your location in relation to the environment or to know where other objects are in relation to you. Far Vision -- The ability to see details at a distance. Control Precision -- The ability to quickly and repeatedly adjust the controls of a machine or a vehicle to exact positions. Problem Sensitivity -- The ability to tell when something is wrong or is likely to go wrong. It does not involve solving the problem, only recognizing there is a problem. Glare Sensitivity -- The ability to see objects in the presence of glare or bright lighting. Night Vision -- The ability to see under low light conditions. Near Vision -- The ability to see details at close range (within a few feet of the observer). Oral Expression -- The ability to communicate information and ideas in speaking so others will understand. Response Orientation -- The ability to choose quickly between two or more movements in response to two or more different signals (lights, sounds, pictures). It includes the speed with which the correct response is started with the hand, foot, or other body part. Number Facility -- The ability to add, subtract, multiply, or divide quickly and correctly.

Operating Vehicles, Mechanized Devices, or Equipment -- Running, maneuvering, navigating, or driving vehicles or mechanized equipment, such as forklifts, passenger vehicles, aircraft, or water craft. Identifying Objects, Actions, and Events -- Identifying information by categorizing, estimating, recognizing differences or similarities, and detecting changes in circumstances or events. Getting Information -- Observing, receiving, and otherwise obtaining information from all relevant sources. Communicating with Supervisors, Peers, or Subordinates -- Providing information to supervisors, co-workers, and subordinates by telephone, in written form, e-mail, or in person. Monitor Processes, Materials, or Surroundings -- Monitoring and reviewing information from materials, events, or the environment, to detect or assess problems. Making Decisions and Solving Problems -- Analyzing information and evaluating results to choose the best solution and solve problems. Coordinating the Work and Activities of Others -- Getting members of a group to work together to accomplish tasks. Inspecting Equipment, Structures, or Material -- Inspecting equipment, structures, or materials to identify the cause of errors or other problems or defects. Processing Information -- Compiling, coding, categorizing, calculating, tabulating, auditing, or verifying information or data. Monitoring and Controlling Resources -- Monitoring and controlling resources and overseeing the spending of money.