Fishes are aquatic creatures that live in freshwater or saltwater for most or all of their lives. You can’t deny that you have been fascinated by these sea creatures at some point and wondered about their diverse characteristics.
We all know that fishes, like other aquatic beings, need water to survive. Still, many times over, I have thought about the possibility of fishes living out of water.
And, even though living on land is somewhat unusual for fishes, it turns out that many species can survive without water for some time.
The question arises, how long can a fish live out of water? Below, we will find the answer to this question and, perhaps, a few reasons to be more fascinated.
How Does Fish Survive in Water?
As fish do not require atmospheric oxygen, they spend most of their lives underwater. Their respiratory system relies on oxygen dissolved in the water.
The dissolved oxygen flows around the fish under the water and passes through its gills when they open. As the oxygenated water passes through, the tiny blood vessels in the gills extract oxygen and discharge the waste back into the water. That is how fish breathe.
The respiration process of the fish is somewhat similar to humans. Like we have lungs to extract oxygen from the air, fish have gills to extract oxygen out of water.
The opposite is, however, not true. That is why, if they stay for longer, humans will drown in the water while fish will die on land.
However, both these creatures will survive for some time before they can’t breathe. Ultimately, fish will die if they remain out of water for too long, but the question is the duration of their survival before they can’t breathe anymore.
I am concerned about the time it will take for the gills to collapse after they lose contact with water. And that forms the basis of this post.
How Long Can a Fish Live Out of Water?
Thinking of fish outside of water, the idiom “Fish out of water” comes to mind. It refers to an individual who is uncomfortable in a particular surrounding, just like a fish out of its natural habitat. The expression brings the image of a fish that is flapping its fins, struggling to find water.
But, not so fast. Before it dies, fish can survive out of the water, some species even for years.
We know that fish get their oxygen from water, but some species can also get oxygen supply through their body mechanisms such as skin. These fishes are naturally amphibious beings. The bigger fish can also store oxygen to survive in deep water.
How long can a fish live out of water depends on its species, size, environment, or the natural habitat they belong to.
If your goldfish fish jumps out of a fishbowl, it can survive as long as its gills remain moist, and the fish can breathe the dissolved oxygen. In this case, the surface on which it lands matters a lot.
The temperature of the place will also play a significant role in determining if the fish will survive outside water.
That said, your pet fish should not be kept out of the water at all, and never for more than 10 minutes. Most pet fish would not last even that long if the environment is dry or the temperatures are too high or low.
Factors Behind Survival of Fish Out of Water
Here are three main factors that determine how long a fish will survive without water.
How long a fish will survive outside water will depend on its type. The amphibious fish can stay for hours to days and even years outside of water. That’s due to their body mechanisms designed to withstand harsh conditions.
Pet fish, on the other hand, only survive for a few seconds to a couple of minutes before their gills dry out, and they suffocate.
The amount of energy a fish needs to stay alive is another factor behind the duration of its survival outside water. The metabolic rates depend on the environmental conditions of their natural habitat, such as temperature, as they affect their body temperature.
For instance, fish that live in colder temperatures have slower metabolic rates, which means slow oxygen consumption and longer survival duration.
How long a fish will survive without oxygen supply from water also depends on how much oxygen it needs. The fish with slower metabolic rates have lower oxygen demands, so they are more resilient outside of water, even without any external oxygen supply.
Fish That Survive Out of Water for Longer
I have given you a general idea of how long can a fish live out of water and the factors behind it. Since there is immense uniqueness among the fish species, it means that some fish are tougher out of the water than others.
Below, we explore some specific types of fishes and how long they can survive away from their natural habitat.
This fish is amphibious and can survive for a long time out of water. The Mangrove Rivulus leaps out of the water on its own when the water becomes too warm.
Over time, this one has evolved enough to breathe through its skin while it is away from water. Their skin is one feature that allows them to survive on land for two months, which is longer than most fish can.
Mangrove Rivulus can be found in marine waters such as the Caribbean and parts of the Atlantic ocean.
The Walking Catfish
This is a type of freshwater catfish native to Southeast Asia. Over time, the fish has developed an extra organ that aids their gills to inhale oxygen from the air. After big rainstorms, the Walking Catfish wiggles or “walks” dry land to find their way back to the water.
The Mudskipper can survive on land for most of their life. Amphibious fish have blood vessels close to the surface of the skin, which makes it easier to absorb oxygen into their bloodstream. It enables them to spend most of their life outside of water.
Mudskippers have pectoral fins on their bodies that look and work like legs. They help them “skip” across muddy surfaces and even climb low branches.
Their skin is adapted to muddy surfaces from birth. That’s why they have adopted this system of breathing through their skin.
This amphibious fish can be found in some parts of Africa and Asia. As the name suggests, snakehead fish have elongated bodies and a diet consisting of planktons, small fish, and frogs.
Usually, snakehead fish can survive on land for up to six days. Some can even survive for months as they are out in search of new habitats or prey.
You may have seen or at least heard of eels that are usually found on sandy and rocky lands. They also have the ability to breathe through their skin, and they dig holes in sand or mud to survive in the shallow waters.
Very similar to the lungfish, the Climbing Perch have both lungs and gills, which allow them to survive in harsh environments. The type is native to Asia, but the species can thrive on fishing boats and reach completely new locations without dying on the way.
The Climbing Perch can survive out of water anywhere from six to ten hours. They can also move on land by wiggling their body forward.
Found in fresh and brackish waters, Plecos have adapted to survive out of the water by developing the ability to breathe through their skin. They can also store oxygen inside their belly to survive for up to 30 hours without water.
This type of fish has tough skin, which enables it to survive harsh and dry living conditions as they “wiggle” on dry land to find new habitats.
There are trillions of fish in the ocean, and many are not limited to spending all their lives underwater. Many fish have unique survival mechanisms that help them thrive on land when the need occurs.
While some can survive for months, others die in a matter of seconds when they are not in water.
I hope this post has answered your question – how long can a fish live out of water? However, the fact remains that fish ultimately need water for survival, so you don’t want to test the capabilities of your pet fish by keeping it away from moisture.