Final answer:
Anchored vessels must display an anchor light at night to indicate their status and location.
Step-by-step explanation:
When anchored outside a designated mooring area, anchored vessels must display the proper lights at night to indicate their status and location. According to international maritime law, vessels must display an anchor light, which is a white light that is visible in all directions, to indicate that they are at anchor. This light must be placed where it can best be seen to avoid confusion and potential collisions with other vessels.
Additionally, the anchor light must be displayed from sunset to sunrise and during periods of restricted visibility, such as fog or heavy rain. It is important for anchored vessels to comply with these requirements to maintain the safety and orderliness of maritime traffic.