Which color indicates the starboard side of the channel?

The color that indicates the starboard side of a channel is red. In marine navigation, red marks are used to denote the right side of a channel when entering from the sea or heading upstream. This is part of the IALA (International Association of Lighthouse Authorities) buoyage system, which helps mariners identify navigable waterways and their respective sides.

Red buoys or marks are usually characterized by their color and can also be identified by their shape. For instance, in the IALA system, red buoys are typically cylindrical or can-shaped, and may have the top marked with a red triangle or point to indicate that it is a starboard mark.

A fundamental rule for mariners is to keep red marks on their right side as they enter a harbor or navigate through a channel, which reinforces the idea that red signifies starboard. This visual cue is essential for safe navigation and helps prevent groundings or collisions in congested waters.

While other colors, like green, commonly signify the port side and may be used for navigational aids, they do not represent the starboard side. Yellow and black are not standard colors used to indicate either side of a navigational channel.