How Do Jellyfish Eat? + What Do They Eat?

Do you ever think about how jellyfish eats and how they digest their food? Because even me, I never knew the answer before. But when I started to become hooked up with pets, I became more into animals. 

I have done lots of research about how jellyfish eat and how they digest their food. What you will see inside this article is everything that you need to know about the eating habits of jellyfish. So let us get back to the main question: how do jellyfish eat? Here is the answer:

How do jellyfish eat? Jellyfish are passive animals when it comes to finding food. They will only capture foods near to them, and their favorite food is plankton. Jellyfish can move to attract foods. They have 4-8 oral arms. That is why they can effortlessly capture food and put it in their mouth. 

However, we have a long version of it. What I mean is, I have a list of steps of how jellyfish eat. The steps are from how they hunt their food to releasing their manure. 

Aside from that, I will also answer various questions related to our subject. Now if you are ready to know more about jellyfish, let us keep moving forward! 

Related Article: How do snails eat?

Broad Answer About How Jellyfish Eat

Let us take a deeper look at the answer to our main question: how do jellyfish eat. This is the detailed version of how jellyfish eat. 

Like I have mentioned, jellyfish will not move as possible to search out for food. Jellyfish are like kings because they just float around and will eat any edible creatures that float near them. However, sometimes, jellyfish will move to attract their prey. Once they attract their prey, it is a sure meal. 

Let us check it in more detail.

Jellyfish Will Use Their Tentacles To Catch Food

Like I have said, jellyfish have many tentacles, and their tentacles are long. They use their tentacles to capture their food. 

While the plankton swims near the jellyfish, and once it does touch the jellyfish it will stick into its tentacles. Even if the plankton is not that near the jellyfish, jellyfish no need to be stressed. Why? Because their tentacles can reach up to 100 feet! 

When the plankton touches the tentacles of the jellyfish, it will get poisoned. Not just planktons actually but other prey of the jellyfish. Any food that will hold the tentacles of the jellyfish will be paralyzed and will die soon. When it dies, the jellyfish will enjoy it!

Some jellyfish species have a stinging thread curled inside them. That thing can be thrown out towards the prey, and usually, bigger jellyfish are the only ones with that power. 

Jellyfish Will Put The Food Inside Their Mouth

The oral arms that are near the mouth of the jellies will seize that food and put it inside the mouth of the jellyfish. 

These oral arms are much shorter and smaller than their tentacles. It will always grab the plankton and other food and move it directly to their mouth. Yes! Jellyfish have mouths. Their mouth is planted in the center of them and directly linked to the stomach. 

The mouth of the jellyfish is like a little black hole. The mouth of jellyfish is just used to do some basic stuff like putting the food directly inside the stomach and is also used to move their body forward. Yes! The mouth of the jellyfish is also in charge of their movement. 

Jellyfish Will Digest Their Food

Once the plankton or other food they have captured is placed inside their mouth, it is time for the jellyfish to digest it. Yes, it is a game over for the plankton. Jellyfish have the same digestive system as anemones.

There is no trick or other gimmicks. The way jellyfish digest their food is simple! Once the food enters the mouth of the jellyfish, it will immediately end up inside their stomach. 

Jellyfish digest food with the use of coelenteron. It is the same thing with the human’s stomach and intestines. We can find lots of enzymes inside it that will help digest the food. The food jellyfish has captured will be digested through the cells inside the stomach, and the rest will be ejected out again. 

Do Jellyfish Have Anus?

Now that jellyfish have eaten and digested the poor plankton it is time for releasing their feces. However, jellyfish have no anus! So how can they release it? 

Because jellyfish have no anus, they have to release their waste from the food they ate in the same way it came in. Yep! They will eject their feces from their mouth!

Jellyfish Is In A Hurry

Jellyfish eats like you when you are late for office or school. They will eat fast, not just fast, but super fast! Why? Because jellyfish can’t swim around the ocean with some planktons inside them.

But because they only eat little stuff, it will not take time for jellyfish to digest the food they intake. In simple words, they can hunt, eat, digest, and release their feces in just a few minutes!

What Are The Foods Jellyfish Love To Eat?

Now you know how jellyfish eat. Let us next find out what foods they crave. However, their favorite food depends on their size. It means that mini jellyfish have different food compared to big jellyfish. 

Let us start with the mini jellyfish. 

Small Jellyfish

The smaller jellyfish are carnivorous, which means they will eat various tiny organisms that they can find floating in the ocean. The small jellies will usually eat:

  • Plankton
  • Larvae
  • Tiny fish
  • Plants
  • Fish eggs
  • Plankton eggs
  • And other small creatures they can found in the ocean

It can be a disaster for the small fishes near lots of jellyfish because they will be killed. After all, jellies will eat anything smaller than them!

That is why if a small fish sees that there are lots of jellyfish, they have to go somewhere else to live or find food. However, this is not a problem for fishes. Why? Because they are much smarter when compared to jellyfish. 

Jellyfish has no brains! That is why they cannot follow the fish. Jellies are not smart enough to do that. Jellyfish that are swimming together are called a bloom. One bloom can consist of millions of jellyfish, and they can cause problems for fish and fishermen. 

When the fishermen see lots of jellies, they have to move at different locations or wait for the jellyfish to be moved by the ocean in another direction. Now let us check what the big jellies eat!

Big Jellyfish

Enormous jellyfish can kill huge organisms because they are big enough to execute them. They have poisonous stings and can shoot out the sting whenever a fish or crustacean trigger it by touching their long tentacles. 

Once they sting the animal, it will be killed or become unconscious. Once these two things happened, the jellyfish will put it inside their mouth. The favorite sea creatures jellyfish loves to eat are:

  • Lobsters
  • Barnacles
  • Crabs
  • Plants
  • Shrimps
  • Bigger fishes
  • Planktons
  • Eggs of the bigger fishes

The larger jellyfish can also eat other jellyfish that are smaller than them. Yes, large jellies are cannibals. However, they are not like lions or cheetahs that know what they eat because they have no brains. It is a complete instinct. I wonder if they enjoy the taste of the foods they intake. 

Jellyfish will eat anything that will swim near them. And even if it is a big living thing, jellyfish can digest it quickly. 

Who Are The Predators Of Jellyfish?

I know that jellyfish may be a bad guy because they eat whatever they like, even if it is a mother fish with baby fishes waiting for her to come home. However, even though jellyfishes are predators, they can also be prey for some animals like:

  • Spadefish
  • Sunfish
  • Sea turtles
  • Other jellyfish (big jellyfish) 
  • Sea anemones
  • Tunas
  • Sharks
  • Swordfish
  • Penguins

Aside from that, humans also eat jellyfish. However, you can only see jellyfish at expensive restaurants around the world. You can see lots of them in restaurants in Asia.

Jellyfish are sold to seafood companies across Japan, China, and Thailand. Humans dry the jellyfish first and package it before they export it to the seafood companies.

How Many Jellyfish Species Are There?

There are 200 species of jellyfish that are floating under the ocean. There are small and big jellyfishes. Most of these jellies are dangerous to sea creatures but not to humans. However, they can still cause you irritation if you try to touch their tentacles.

Can Jellyfish Eat A Human?

No! Like I have mentioned above, jellyfish are not dangerous for humans but can still cause some mild injuries if the tentacles are touched. Jellyfish will only eat small sea creatures under the ocean.

Final Verdict

Jellyfish will passively look out for their food. However, jellyfish might make a move to attract prey. Jellyfish use their long tentacles to grab their food. Once they successfully kill their prey, they will transport it directly inside their mouth. 

They will release their feces from their mouth too. Why? Because they have no anus. Jellyfish will eat fast since they cannot move while they have something inside their stomach. 

Source: animalhow.com, kids.nationalgeographic.com

About
Jake Willhoite
Jake runs AnimalDome.com and has had cats and dogs his entire life. As a kid his family adopted several dogs from the local shelter which set him down the path of animal rescue.
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