How Are Can Buoys Marked?

How Are Can Buoys Marked?

If you have been boating, you are probably wondering what the different buoys in the water mean, and how you should react to them. In this guide we will be answering what can buoys specifically are designed to represent.

On top of this, we will also cover what other buoys are supposed to represent as well so you know how to differentiate them from other buoys.

So, if you have seen can buoys in the water before, but you have no idea what they mean, or how to react to them, keep reading to get all the information you need! For a quick answer, a can buoy can be recognized for its cylindrical shape.

You will nearly always find them having green markings and will be marked using odd numbers. These can buoys are used to mark the edge of the channel on your port (or left) side.

This will show you where you are entering in from the open sea, or perhaps heading upstream. The numbers on the buoys will increase if you are returning from open sea or heading upstream, and will go down when doing the opposite.

Now you know this information, you should know how to appropriately react when boating near these buoys. However, there is still a lot more information to know when you are boating around buoys, and this is only part of the information you should know.

So, if you want to learn more about buoys, and what they mean, this guide should give you all the information you are looking for. So, if you want to ensure you have all the information you need before boating, keep reading!

More On Buoyage And Navigation Marks

More On Buoyage And Navigation Marks

As we established in the first section, there are green can shaped lateral buoys, and these are used to mark out the left side of your boat when you are returning from open water or heading upstream.

However, if you feel like you might struggle to remember this, there is a technique you can use where you remember the opposite side markers to help remember the green ones.

This is because the green can shaped markers are not the only buoys used. In fact, there are also red buoys, and these mark out the other side of the green buoys.

These, instead of being on the left or the port side of the boat, are intended to be on the starboard, or the right side of the boat.

So, if you see a red buoy, these are intended to show the right side of the boat when you are returning from open water, or instead heading upstream. As well as this, these buoys will be marked with even numbers instead of odd numbers.

These even numbers will increase the closer you get. The reason why these red buoys are not under the classification of a can buoy is because they are not can shaped like the green buoys.

Instead, these red buoys tend to be cone shaped at the top, and instead of being called can buoys, they are more often called nun buoys instead.

If you want an easy way to remember what nun buoys represent, you can remember ‘red, right, returning’ because they are red, on your right, and represent you are returning, and you can use this to remember that the green buoys are on your left too!

The green and red markers that we just mentioned are known under the bracket of lateral markers, so if someone asks you what color lateral markers are, you can tell them red and green, and how they are used.

However, these are not the only buoys that are used and you can use other buoys as sources of other information, so you want to keep this in mind when you are boating. Knowing what all these buoys mean is incredibly important.

Another type of buoy which you should keep an eye out for is a safe water marker, these will be white with red stripes and they will indicate that there is safe open water on either side.

You can also use buoys like this as markers for the center of a navigable channel. You can pass these markers to the port or the starboard side.

Furthermore, you can also find that these buoys will occasionally have a white light, so this is another sign you can use to spot them! Another common type of buoy which you should be able to understand are inland water obstruction markers.

The goal of these buoys is to give you information about different hazards in the water. These are usually white with black stripes in a vertical direction. You do not want to pass between them and the closest shore.

However, they will often have lights which are used to indicate which direction you could pass them in. They will flash the lights to tell you which direction is the best to cross by.

If the light flashes 3 times you should pass by it east, but if it flashed 6 times and then one long flash, that means you should pass by south. Then if there are 9 flashes you should pass by west, and if you should pass by north, it will be flashing continually.

Knowing what flashing indicated what direction is a useful skill you should definitely know as it will ensure you do not run into any obstacles when boating!


Hopefully this guide has given you all the information you need on how to recognize can buoys, and what their markings and color mean. If the buoy is can shaped, it is likely that it will be green and marked with odd numbers.

This means that the buoy should be on your left or port side if you are returning from open water, or if you are going upstream. If you want to know what color the buoys will be on the right side, then these will be cone shaped and red with even numbers instead.

Leave a Comment

Your email address will not be published. Required fields are marked *

Special offer for our visitors

Get your Boat Building Free Guide

We will never send you spam. By signing up for this you agree with our privacy policy and to receive regular updates via email in regards to industry news and promotions