Why Do Fish Jump Out Of The Water?

Have you ever wondered why fish jump out of the water like crazy? It’s pretty spectacular scenery if you ask me. Well, as long as they don’t jump and slap all over me and my yak with their fishy, watery tail. 

Fish are known to live under the water, and we usually don’t see them jumping or leaping out of the water. Well, some fish do it sometimes. But why?

There is a diversity of reasons behind this behavior. Some are more obvious than others. Sometimes fish jump out of the water to evade danger, sometimes to be the danger (to hunt). 

They can jump to overcome obstacles or to complement the scarcity of oxygen in the water. Or it can be as plain as a stress response. Not always is the reason obvious. Some of the time, the reason is pretty predictable. But other times, it is not. 

To be fair, on occasions, fish jumps out of the water just because they can. Odd as it may sound, fish also leave the water as a means of migration or to inhabit new water bodies.

Why Do Fish Jump?

So, here are some of the common reasons for fish to jump out of water –

To Evade Danger

Fish are known to be carnivorous, and small fish fall prey to the big fish most of the time. More often than not, the big fish are more dexterous. They ambush and engulf their prey. But sometimes, the smaller one gets just enough time to realize and react. 

While the smaller fish are more agile, the bigger ones are stronger and faster. Swimming in a straight line is not a reliable escaping method. 

If the smaller one jumps and leaves the water, even if it is for a short time, it breaks the line of sight and makes the bigger one fuzzy. In the process, it buys itself just enough time to survive another day.

It is more effective, thus, more common in swampy areas, where there are plenty of obstacles in the water. Marlin and Largemouth bass jump out of the water when hooked, which is also a defensive maneuver.

To Hunt

Most of the fish species are carnivorous by nature, but only the bravest and craftiest ones take to the air. Yes, some fish species are known to hunt airborne prey like grasshoppers, butterflies, or other smaller insects.

When an insect is resting on a branch right above the water, most fish simply swim by. But marbled hatchet fish has a different idea. They leap out of the water to knock the insect down in the water. Then it’s as easy as a meal can be.

Needlefish does it for the same purpose but in a different manner. Needlefish are sleek and fast. But they live in clear water, where it is difficult to sneak on its prey. 

Most of the fish have great eyesight underwater, but they are shitty above water. Needlefish takes advantage of it. When it leaps above water, they are practically invisible to their prey. You know the rest.

African Tigerfish has been documented to leap above water to grab low flying birds and bats.

To Supplement The Scarcity Of Oxygen In Water

When the water is murky and thick with dirt, algae, plankton, or other biomass, the oxygen level drops drastically. While the microbes thrive in this water, fishes do not do nearly as well. Nearly all of the fish species in such a water body are noticed gulping at the water surface. Some just take it a step further and jump.

Yes, fish can exchange oxygen and carbon dioxide from the water. It’s just they are very bad at it. Most of the time, their gills collapse and stop working when they are above water for an extended amount of time, but when the water is running low on oxygen, a “leap” can supplement that.

To Get Past An Obstacle

Fish sometimes jump out of the water to get past obstacles. The most iconic example is the annual salmon run. They climb up waterfalls regularly solely by jumping. Other fish also do similar stuff, but not as crazy as climbing waterfalls in reverse. 

Comet goldfish and killifish are aquarium fish that are known to jump out of their bowl. When the living condition is far from ideal, they jump out in an attempt to find new living space. Other pet fish may jump out if they do not get sufficient hiding spots or feel too confined to relax.

Fish that live in flowing water are known to be more agile than their still water cousins. If their natural path is obstructed, they take a breath and “jump” past it.

Stress Response

Asian carp is a good example of fish that jump out of water when they are scared. If you go for fishing with a motorboat then the sound of the engine may create stress among the fishes as the motorboats get close to their living space, they go mad and jump like lunatics.

Some say that the engine noise spooks them and triggers the survival instinct, like the fainting of Tennessee fainting goats (Did you know they literally faint when they are spooked?).

Another theory is, the engine noise of an average boat resonates with the swim bladder of these fish, making them violently uncomfortable from the inside. As a result, they freak out and try to leave the water.

But if you go with a kayak sound will not be a problem. This is one of the basic difference between kayak fishing and boat fishing.

Breeding

Breeding is a natural phenomenon; every single animal performs, including fish. To some, this means crossing over great distances and reaching a specific location. If there are obstacles in the way, they will search for ways to pass it, including leaving the water. 

Dams, waterfalls, and Netting are some of the obstacles that might not have been there the previous year. But if the fish is challenged and unable to find a way, they will eventually jump to be creative at solving the issue. Again, salmons are a remarkable example.

Migration

Some migratory fish jump out of the water regularly to explore and expand. Koi and other carp fishes are smarter than your average fish and like to explore their surroundings. 

When you add new carp to your pond, especially koi, they are often seen jumping out of the water, more so if there is an artificial waterfall. Vietnamese koi is a common pond fish in Asia, and nearly all of the koi population jumps out of the water at the first rain of the year. 

A theory stands as if they want to break free from the barrier of the same pond they’ve been living in for the past year and look for a new pond. They use the rainwater as a portable oxygen source, like scuba diving, but on the land.

Conclusion

Those are some of the reasons why fish jump out of the water. The reasons vary from species to species, from region to region, from time to time. As mentioned above, sometimes the reason is simple and clear, but other times speculation is all we can do. Nonetheless, it is an interesting phenomenon to see.

Sometimes fish jump out for reasons, sometimes randomly, which we are unable to get a reason for. Either way, they do their business, and we get amusement (or watery slap). Anyway, it is a natural phenomenon, and it is here to stay.