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Channel marker Yarra River.
Melbourne.
A Nun Buoy marks the Left side of the channel leaving the harbor. It will be red and have even numbers on it. Red Daymarkers are often used in shallow areas for the same purpose.
If the red marker has pilings supporting it, it will be called a dolphin. Red buoys with lights will usually be found in deeper water. The light will be red. Larger buoys may also have bells, horns or other sound producing devices. Original public domain image from Flickr
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