What marker is used to indicate not to pass between the buoy and the shore?

The marker used to indicate that vessels should not pass between the buoy and the shore is typically a red buoy or a navigational marker displaying a "keep out" or "no trespassing" sign. These markers signal that the area may be hazardous or designated for certain activities, such as swimming or fishing, and are part of safe navigation practices. Always pay attention to local regulations and navigational charts for specific guidance.