What feature often distinguishes a starboard buoy?

In the IALA Maritime Buoyage System, a starboard buoy is typically distinguished by its green color. The presence of a green topmark is a critical feature that designates a buoy as marking the starboard side of a channel as one is proceeding in the direction of buoyage. This visual cue is essential for navigation, allowing mariners to easily recognize the safe side of the channel, which aids in avoiding hazards and ensuring that vessels are correctly aligned within the navigable waters.

Other aspects such as the shape or top surface of the buoy may vary, but the green topmark remains a universally recognized characteristic associated with starboard buoys. Understanding this key feature is vital for effective navigation and safe passage through channels.