How Do Fish Sleep? Oh It Turns Out

How Fish Sleep – Has Sinaumed’s ever observed fish movements, either in an aquarium or in a pond? When observing these movements, has it ever occurred to Sinaumed’s whether fish are sleeping or not?

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The answer is of course yes! Fish, like other living things, also sleep. Fish both need rest, but the way they sleep is certainly different from other living things. How does it feel to sleep underwater…

Then, how about sleeping from a fish because its eyes never blink and close. Is it true that the fish sleeps deliberately widening its eyes, aka literate?

So, so that Sinaumed’s isn’t curious, let’s look at the following review!

The Process of Sleeping Fish

Please note that most fish do not have eyelids, except for sharks. Therefore, if you pay close attention, the fish will always open their eyes so it will be difficult to tell which fish are asleep or not.

Most of these fish lack a neocortex (a set of cortical layers of the cerebrum, usually in mammals, that is used in higher-order brain functions) and an eyelid. By not having these two parts of the organ, it causes the side of the fish’s brain to close and their eyes cannot close.

In fact, when a fish is asleep it is not really asleep, but only half awake. In fact, the fish’s tail can still be moved to ensure that the flow of water is maintained towards the gills. This is done so that the fish do not lack oxygen and keep breathing.

Not sleeping the fish is also to avoid himself from all threats of danger or attacks from other fish which can later cause him to be injured to death. So, it can also be said that fish sleep in a state of alert.

When in an aquarium or pond, the fish will fall asleep by floating their bodies in the water. However, when in the ocean, fish will fall asleep in their hiding places, namely behind coral reefs so that they are not caught by bigger fish.

Even unique, some types of fish will sleep by pretending to be dead fish by laying their bodies on the bottom of the water.

Different types of fish, different ways of sleeping. Sharks that have eyelids even sleep without closing their eyes, accompanied by slow swimming movements. If a comparison is made, then the sleep of the fish is almost the same when humans are daydreaming.

Then there is also a type of parrot fish or parrot fish that has a “sleeping bag” in the form of a slimy jelly. The “sleeping bag” seems to wrap around his body and become his bedroom when he sleeps so that he can be free from predators.

When Do Fish Sleep?

In general, most of the fish are diurnal. Contrary to nocturnal, diurnal is a term for animals that carry out activities during the day and sleep when night falls. Almost the same as humans huh…

This is because during the day the habitat will definitely get a supply of sunlight as lighting, making it easy to find food.

However, the exact time the fish sleeps depends on the fish species. Some sleep during the day, but some sleep at night. There are also some fish that can only sleep for a certain time, for example during migration.

Then, there are also those who don’t even sleep at all until they are adults, for example tilapia fish. Tilapia fish will usually sleep when they are more than 22 weeks old. If the ornamental fish are usually placed in the aquarium, then they tend to sleep when the aquarium lights are turned off.

Characteristics of a Sleeping Fish

If Gramed is still curious about the characteristics of a sleeping fish, let’s look at its special features:

Pause the movement of fish when swimming more regularly, especially at certain times.
Fish become “inactive” for quite a long time.
Fish in a calm posture, as if resting.
His sensitivity to external stimulants decreased.

Fish Bed

If placed in an aquarium and there are rocks as decorations, the fish will usually hide behind the rocks. However, it is possible that fish can also sleep like swimming as usual. When in an aquarium, fish tend to be “relaxed” in sleeping behavior because there are not so many disturbances or threats from predators.

Meanwhile, when fish are in the ocean, they will behave especially at night by choosing nests with a distinctive shape, such as holes or crevices in caves, under ledges, in sponges, and some even bury themselves in the sand.

Unique Ways of Fish When Sleeping

There are many species of fish, so that between species, one with another, of course, has a unique way of behaving in sleep. What are the fish that have a unique way of behaving in their sleep? Come on, see the following reviews!

1. Loach fish

The loach fish, which belongs to the order Cobitidae , turns out to have a unique way of behaving when it sleeps, namely by turning or stretching its body, as if it were dead.

If you keep this type of fish, then suddenly its body flips over, don’t panic. He could just be sleeping to rest his body.

2. Coral Fish

There are many types of reef fish that can be consumed, ranging from Serranidae (grouper), Caesionidae , (Yellow Tail/Banana-Banana), Scaridae (Cockatooo/Mogong), Balistidae (Poge/Trigger), Pomacanthidae (Enjel/Goat), and Siganidae (Baronang/ Keakea/ Lingkis).

Well, this time we will discuss one of these types of reef fish, namely the Damselfish. The distinctive feature of this fish is its bright color, so many people are interested in keeping it.

When sleeping, Damselfish tend to hide between coral branches. This is also a way to avoid predators that will prey on it.

3. Cockatoo Fish

The Cockatoo Fish or often referred to as the Parrot Fish also has a unique way of behaving when sleeping, namely by wrapping its body using a kind of slimy jelly-shaped bag.

The slimy sac is produced by the Cockatoo Fish through its mouth. Not only used as a “sleeping bag”, it turns out that the slimy bag can also protect it from Gnothi Isopods attacks .

Gnothi Isopods are a type of sea-sucking shrimp. If in the sea, these shrimp can be referred to as “sea mosquitoes”, and it turns out they are a type of fish parasite.

4. Sharks

Surely Sinaumed’s is no stranger to this big fish, right? Yep, this fish is feared by many other fish because of its sharp teeth and is the most ferocious predator in all of the oceans. Not only prey on fellow fish, but also humans.

The unique way sharks behave when they sleep is to sleep for a while, even just blinking their eyes a few times. Remember, that some fish don’t have eyelids, except for sharks.

There is even research on sleep behavior patterns in these sharks. When sleeping, sharks tend to stay still, with their eyes continuously open and their pupils still monitoring the movements around them.

There are even several species of sharks that can sleep and not move at all, for example the Lemon Shark, Caribbean Reef Shark, Wobbegong Shark, and others.

5. Dolphins

It should be understood that dolphins are not actually fish, because they do not have gills as breathing apparatus and the breeding process is not by laying eggs. Instead of using gills, dolphins have lungs that can be used as a breathing device and when the process of reproduction is by giving birth. Therefore, dolphins are included in the type of mammal.

Many people misunderstand that dolphins are a type of fish because of their habitat in water, when in fact dolphins are aquatic mammals.

By making the lungs a breathing apparatus, of course the dolphins have to hold their breath for 15 minutes and then “jump” to the surface to take a breath. Then dive back into the ocean.

Even when sleeping, dolphins “unknowingly” will also push their bodies to the surface to take a breath. If not done, the dolphins will run out of breath and may die.

Fish Unique Facts

This type of animal that relies on gills as a breathing device and lives in water is very familiar with everyday human life. Not only useful as pets, but also can be consumed as side dishes that have high nutrition.

Then, what are the unique facts about fish that not everyone knows? Come on, see the following reviews!

Through evidence in the form of fossils, states that fish have lived on this planet Earth for approximately 530 million years ago.
There are more than 32,000 species of fish spread all over the world. This number is even more than the number of all types of vertebrate animals.
Many types of marine animals are often mistaken for fish when they are not, such as octopuses, starfish, jellyfish and crayfish.
Orca whales are the most ferocious type of fish in the ocean and can live for 80 years.
The brain of a dolphin is about the size of a human brain. Therefore this fish is a smart animal.
Dolphins can dive more than 500 meters even though they rely on their lungs as a means of breathing.

Fish don’t have eyelids, except for sharks. Therefore, when sleeping, they tend not to close their eyes.
This type of herring fish can communicate with other fish using its farts.
Even though they live in water, it turns out that fish can see 70 times farther in the air than in water.
This type of Goldfish fish if placed in a dark place, the color will disappear. In addition, these fish can also see the presence of infrared radiation that humans cannot even see.
There is a type of Climbing Gourami (Climbing Gourami) which is able to jump out of the water and then breathe oxygen. Even this fish can also walk using its fins, at close range.
The blobfish actually has a shape like a normal fish, but its shape will change if it is lifted from a very deep sea. This is because his body loses air pressure when lifted.
Fish can cough.
The stingray’s eyes are on top of the body making it difficult to find prey swimming under its body.
Fish that live in polluted places will lose their sense of smell.
The Frilled Shark is a relic fish from the Cretaceous period and is one of the most primitive shark species still alive today.
The most primitive types of fish that are still alive today are the Lamprey Eels and Hagfish.
In the Greenland region, there are sharks that can even eat polar bears and live up to 200 years.
Most of the stingray’s body is made of cartilage, which makes it more flexible when moving in water.

The smallest fish in the world is Paedocypris Progenetica which lives in the forest swamps of Sumatra Island. When mature, this fish only has a size of 7.9 millimeters.
The technique of salting fish to become salted fish was first carried out in Northern Europe which then spread to other regions.
All Clownfish are born male. However, it can also change its sex to female when “needed” for reproduction.
One of the shortest fish in the world is the Pygmy Fish from the Philippines which has the size of rice.
The Mola Mola (Sunfish) does not have a tail.
Catfish have more than 27,000 taste buds. While humans only have 7000 spots.
This type of Mudskipper fish is able to spend time outside the water and can even walk using its fins. When on land, this fish will breathe through the pores of its skin.
The electricity generated by the Electric Catfish is around 350 volts and can cause numbness for a few moments when it is stung.
Mustache or antennae on catfish serve to determine the condition of the place and look for prey at night. It should be noted that catfish are nocturnal animals.
Betta fish are able to heal damaged fins on their own, especially after fighting with their opponents.
This type of fish, Tigerfish Goliath, is capable of eating small crocodiles or juvenile crocodiles.
Sardine is not a fish species name, but a trademark name for canned fish. While the types of fish used are Herring and Pilchard fish.

The phenomenon of raining fish is when a tornado lifts fish from the ocean towards the land, so it looks like it’s raining fish.
This type of fish, Salema Porgy, can cause hallucinations when consumed.
Puffer Fish (Puffer Fish) will inflate its body when it feels threatened. Even so, this fish also contains a deadly poison, namely tetrodotoxin. If you want to consume it, must be prepared by someone who is reliable.
The Tetrodotoxin poison in the Pufferfish’s body is considered 1,200 times more deadly than cyanide and is capable of killing around 30 people.
Seahorses are a type of fish and are the slowest fish, even barely moving at all.
The heaviest fish is the Blue Whale. They can weigh up to 200 tons, which is equivalent to 23 elephants, 230 cows, or 1800 people.
Piranha fish have sharp teeth and the notion that they prey on humans alive is wrong. However, they can prey on human carcasses.
Fish can also drown. If the body does not have enough oxygen, it can cause the fish to suffocate.

Well, that’s an explanation of how fish can fall asleep. It’s the same as humans when they fall asleep, try not to disturb their resting process . If the fish in your aquarium show signs of sleeping fish, it’s better to let them be. Fish is also one of the choices for side dishes recommended by health experts because it has high nutrition.

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