Whether you like snorkeling, diving, or have a fish tank at home, you must have wondered at least once how long can a fish survive out of water. Maybe you are worried about your fish being outside for way too long while you are changing the tank water.
Or perhaps, you are just curious to learn about those fishes that can stay above the water surface and breathe as humans do.
Well, there are various types, size and species of fishes and all of them do not have a similar breathing capability. Thus, there is no fixed time period for how long fishes can stay alive out of water.
Anyway, we shall learn about different fishes and how long each can survive when outside water. But before that, let us get to discover how actually fishes survive in water.
How Do Fish Live In Water
The kind of respiratory system fishes have allows it to spend its entire life in water. They do not require oxygen from the atmosphere to survive. This would only need them to keep swimming back to the surface. They extract the oxygen that they need for survival from the water they live in.
When water flows around the fishes, it gets passed through their gills, which opens and allows the water in. The gills of the fishes are full of little blood vessels. This helps extract oxygen and releases waste gases into the surrounding water. Their gills work the way our lungs do, which also has been designed to absorb oxygen from the atmosphere.
What is also interesting to note is that after swimming for some time, fishes get tired and they depend on the water currents for transportation. This helps them conserve their oxygen supply as well as energy while in the water. This is also what we do when scuba diving.
Once the fish is brought out of the water, their gills would arch and then collapse as it will not be able to find oxygen for their survival. It is not known if fishes feel the pain like humans do in the absence of oxygen, but they will lose their lives of suffocation when out of water.
How Long Do Different Fishes Survive When Out Of Water?
How long can a fish survive out of water is dependent largely on the conditions that they are exposed to when outside water. For instance, you may notice a fish jumps out of a tank and lands on some non-absorbent area with a little water. This fish will stay alive until its gill remains moist and it is able to draw the oxygen from the water surrounding it.
Let us now get to learn about different fishes and for how long each can survive without water.
Pet fishes like Rainbowfish and Goldfish are far weaker compared to saltwater fishes. They even are fragile and have little bodies. Such fishes will suffocate quite fast and die in the absence of water, within around three to four minutes. So, make sure you never take your pet fishes out not unless you are ready to transfer them in new water.
The Mangrove Rivulus or Mangrove Killifish are amphibious. They can easily survive, even without water for nearly a month. As per research, it is possible for these fishes to draw oxygen through their skin if there is no water around. They can even store oxygen. Once they are placed back in the water, they will begin using their gills yet again.
There is an extra organ present in this unique species of fish. It is with its help that their gills are able to inhale oxygen from the surrounding air, the same air that we too breathe. What is more interesting is that they even wiggle or “walk” on the land surface. To do so, the Walking Catfish flexes their body and make use of their pectoral fins and propel themselves. So, do not be surprised if you find a Walking Catfish walking next to you on the road after a big rainstorm.
Many Catfish are even kept alive for sale in a glass tank or bowl with just as much water as can keep them wet. And they can easily stay in this condition for at least 15-18 hours.
Mudskippers are little amphibious fish that can easily survive on land for almost their entire lives. There are blood vessels present near the surface of their skin. It helps them draw oxygen into the bloodstream and that too, without having to actively breathe through their lungs or gills.
The Snakehead fish is known to be able to survive without water for quite long. They can easily stay alive for at least up to six days, and some may even survive in the absence of water for as long as six months. It is basically a freshwater fish and can travel on land in search of a new habitat when it is not happy with its existing one.
Also known as Coral Blenny, it is a freshwater fish that skips around from one place to another in search of new water habitats. They also look for mates when they are on the land. As long as it is able to find food and remains moist, the Rockskipper fish will survive on the land at least for a few hours at a time.
So, how long can a fish survive out of water? Well, it really depends on their species. Some will give up and die in just a matter of a few seconds or maybe minutes. But there are also those that can stay alive in the absence of water for a few hours and some can survive for months.
However, as far as tank fishes are concerned, it will not be a good idea to risk their lives just to see for how long they can survive in the absence of water.
You will never want anyone to trap you somewhere where there is no supply of oxygen. Similarly, you should not deprive the fishes of their needs. Let them swim in the water happily and enjoy watching them as they do so.