What light characteristic differentiates a special mark buoy?

A special mark buoy is specifically identified by its yellow light characteristic, which is critical for distinguishing it from other types of navigational aids. These buoys serve a unique purpose, typically marking areas of special significance such as those designated for fishing, swimming, or other local regulatory purposes.

The yellow light not only indicates that the buoy is designated for a specific use but also helps to prevent confusion with other buoys that utilize different color lights, such as red and green, which are used for channeling and safe navigation. By adhering to this standard, mariners can easily recognize that the yellow light signifies a special mark, allowing them to navigate more safely and responsibly.

In contrast, flashing red lights typically indicate dangers or obstructions, alternating white lights are generally used for preferred channels, and constant green lights signify safe water or navigable channels. Each of these light characteristics serves a distinct function, making the identification of a special mark buoy's yellow light crucial for mariners.