Final answer:
Fishing vessels use specific lights and day shapes to communicate their activities and maneuverability to other vessels. At night, green over white lights are shown for trawling and red over white over red for limited maneuverability. Day shapes include a diamond to indicate gear extending from the vessel and two cones apex-to-apex for fishing other than trawling.
Step-by-step explanation:
Lights and Day Shapes for a Fishing Vessel
The lights and day shapes for a fishing vessel are essential for the safety and communication of activities to other vessels on the water. Fishing vessels use specific lighting configurations to indicate their activity, especially when they are engaged in fishing operations which restrict their ability to maneuver. At night or during times of reduced visibility, a fishing vessel under power will display a green over white light to signal that they are trawling, which means dragging a fishing net behind them. A vessel not under command or restricted in its ability to maneuver will show a red over white over red light. During the day, fishing vessels present two shapes; if gear extends more than 150m horizontally from the vessel, a diamond shape is displayed to indicate it, and two cones with their apexes together in a vertical line should be shown when the vessel is engaged in fishing other than trawling.
In summary, the lighting and shapes serve as a communication tool to inform other mariners of a fishing vessel's presence and operational status, helping to avoid collisions and navigate safely.