What type of buoy indicates the preferred channel on the starboard side when returning to port?

A red buoy indicates the preferred channel on the starboard side when returning to port. This follows the IALA (International Association of Lighthouse Authorities) buoyage system, which is used in many regions worldwide. In this system, red buoys are typically cylindrical and marked with red and white colors, signifying that vessels should pass them on the starboard side when entering a harbor or navigating a channel.

The color coding is crucial for safe navigation, as it helps mariners understand which side of the channel is preferred, reducing the risk of grounding or collisions. Knowing that red is associated with the right side of the channel when heading upstream or towards port helps sailors with correct navigation and maneuvering.

In contrast, green buoys usually indicate that vessels should keep them on their port side while returning to port, providing a clear and systematic way to navigate channels. Yellow and white buoys serve other specific purposes, such as marking caution areas or hazards, but do not indicate preferred channels as red and green buoys do.