I wrote the following a few years back for Junior Bassmaster. It explains how fish breathe and why proper care in a livewell is so important. With that in mind, please check out the V-T2 from New Pro Products. It’s an amazing innovation for maintaining a healthy livewell environment. It’s also easy to install and inexpensive.
If sharks had feet, they would wear out a lot of shoes.
Many species of sharks, along with tunas, must constantly move in order to breathe. That can make it tough to get a good night’s sleep.
Bass and most other fish are lucky. Like us, they can breathe while they are not moving. And like us, they breathe to put oxygen into their bodies so that they can live.
But bass, sharks, and all other fish are very different from us in how they get that oxygen. We breathe in air so that our lungs can obtain oxygen. By contrast, fish push water through their mouths and across their gills, which take in the oxygen that they need. Most fish just open and close their mouths to push the water, while tunas and some sharks must move to do so.
Having gills, makes a bass a real “fish out of water” when you pull it onto shore or into your boat. Unless you treat it with care and put it quickly into a livewell or back into a lake or river, it will die because it can not get the oxygen it needs from air.
Some species, such as catfish, can live longer out of water than others. But always it is a good idea to return a fish to water as soon as possible.
In that watery world, a bass breathes by opening its mouth and drawing in water. As it does that, it closes its gill covers tight over its gill openings. Then it closes it mouth and drives the water over its gills and out with special throat muscles.
Gills are those bright red feathery organs that you see beneath the gill covers, or operculum, on the side of a fish’s head. As water is passed through, oxygen is absorbed through the gills and into the fish’s blood. From there, arteries take it throughout the body. As the oxygen is used up by the stomach, brain, liver, and other vital organs, the blood flows to the heart, where it is pumped back to the gills.
Some water is better for breathing than other water. That’s why you should keep your livewell --- and your aquarium at home--- aerated. That means using turbulence from a pump to put oxygen into the water.
You must do this because fish, like us, produce carbon dioxide as waste as they breathe. In a closed container without aeration, a fish soon would use up all of the oxygen and die of suffocation, just as it does when left out in the air for too long. Turbulence replaces the carbon dioxide with live-giving oxygen.
Pumping oxygen in becomes even more important as the water heats up. That’s because warmer water can’t hold as much oxygen as can cooler. Also, a bass needs more oxygen in hot weather because it is cold-blooded and higher temperatures make it more active.
Bass sometimes die in small, shallow ponds during summer, because the water is so warm that it can’t hold enough oxygen for the fish to survive.
In the north, they also might die of suffocation in the winter, when ponds and lakes freeze over. Ice keeps the water from absorbing oxygen from the air. Also, snow cover on the ice can be a killer, as it prevents sun from reaching underwater plants. Without sunlight, plants don’t “breathe” in the water’s carbon dioxide and breathe out the oxygen that fish require.
But such “kills” don’t mean that bass are delicate creatures compared to other fish. Under the same circumstances, just about any other freshwater species would die as well.
Actually, bass are among the most hardy and adaptable, which is why we can fish for them in 49 of the 50 states, from the icy waters of Montana to the sun-warmed waters of Florida.
Wherever you catch them, though, don’t forget that a bass needs water in the same way that you need air. As quickly as you can, let that fish breathe again.