Did you know trout burp?!

Hi everyone,

Check out this video of a trout burping and keep reading to find out how it works!

Ever wondered how your trout can move up and down in their tank or in a lake? It may seem as simple as them just swimming up or down, but the physics are actually much more complicated. Water has different densities and more or less pressure at different depths, so your trout has to adjust as it moves through a water column (if you think about your body of water as an excel sheet, the column is the up and down dimension).

Your trout moves through the column of water by adjusting its buoyancy (fancy word for how much it floats or sinks). To adjust to different depths of water and change between them, your trout has a swim bladder. This swim bladder can fill with air to make the trout more buoyant, so that it floats, or less buoyant, so that it sinks. Swim bladders can be found in trout and salmon and are connected to their throat, so they can pull air into and out of them as they breathe (it's a little like you closing off your lungs when you swallow so you don't pull liquid into them). To release the air the trout burps, like you would after drinking a lot of soda.

Sometimes when a trout is caught in deep water it doesn't have enough time to adjust its swim bladder before it comes to the surface, when that happens you can have to manually burp the trout, as in the video above. If the trout doesn't burp and you release it, it will float belly up if it has too much air in its swim bladder, and can die before it's able to release the air.

You can check out a trout burping in person next time you're fishing with your family!