What does a yellow buoy mark a deep water basin?

A yellow buoy typically marks a deep water basin to indicate an area that may be reserved for specific activities, such as fishing, anchoring, or other maritime uses. The color yellow is often used to signify caution, alerting mariners to exercise care when navigating in the vicinity. Additionally, these buoys may serve as a navigational aid, helping boaters identify safe passage areas or depths in deeper waters.