it doesn't indicate anything, aside from the fact that the buoy is there. the light simply makes it more visible in foggy or dark conditions.
You are traveling upstream on a river at dusk. You see a buoy with the number 4 and a flashing red light. What should you do?
lp
Have the bout on your right
An anchor buoy is a small buoy attached to an anchor by a light line and used to indicate the position of an anchor.
A buoy marked with the number four and a flashing red light typically indicates a specific navigational point in maritime settings. It often serves as a warning or marker for hazards or navigational channels, particularly in areas requiring caution. The flashing red light enhances visibility, especially during low-light conditions, helping vessels identify the buoy's location and purpose.
no
Keep the buoy on your starboard (right) side.
keep the buoy on the starboard side
You go inside that space that has the bouy and stay to the port-side of the bouy.
When going upstream, a buoy with a number 5 and flashing green light indicates the presence of a dam ahead. The dam may be used to generate hydroelectric power or to provide water for irrigation, and can pose a danger to boats and other vessels.
Since this is a Green Lighted Buoy sighted while approaching a harbour,this is a Lateral port hand side mark, IALA region B. To keep this buoy on your port side while travelling upstream.
When you see a buoy with the number 4 and a flashing red light while traveling upstream at dusk, you should treat it as a navigational warning. The red light typically indicates a hazard or an area to avoid. It's important to reduce your speed and proceed with caution, keeping a safe distance from the buoy. Additionally, consult your navigation charts or local regulations to understand the specific implications of that buoy's signal.