How Do Jelly Fish Eat? & What Do They Eat?

Perhaps you might have wondered just how Jellyfish eat, what they eat, and how they can digest the food. Well, we have done lots of research about the Jellyfish, and we have put together in this article everything you’d like to know about the Jellyfish.  

What is the process of food intake for Jellyfish? 

The Jellyfish does not intently scout for food. Instead, it will grab hold of plankton floats nearby. But they have the ability to set themselves in motion such that they attract food. In addition, they have 4-8 oral arms to enable them capture food from the tentacles directly into the mouth.

But that’s only a little bit about them. There’s much more to say about the Jelly Fish, as you’ll find below. We have discovered many amazing facts and cute features about these lovely little fellas. They are twice as funny and crazy as they look.

The Jellyfish are exceptional creatures. The most fascinating of their unique features is their highly simplified nervous system compared to that of other animals and even humans. Based on their size, they tend to eat anything that they come across. So its really exciting to study how it is able to do regular stuff like eating and reproducing.

HOW do Jellyfish eat?

Let’s go a step further and examine the answer in detail.

As we earlier highlighted at the beginning of this article, the jellyfish do not intentionally scout for food. It will casually float around and eat any sort of food that passes its way. An important fact is that the Jellyfish has no brain, so it relies on basic and mechanic things to feed. In more detail here is how it feeds:

1).The tentacles catch the food first:

Jellies have long tentacles that are used in capturing food. Whenever plankton floats by, it immediately sticks to the tentacles. The Jellies tentacles can reach up to 100 feet!, (about 3 meters) for certain species. The feeding process of a Jellyfish is a rather passive one (remember that it doesn’t have a brain) whereby that jellyfish simply floats into these tiny bits and pieces of food by chance.

When the food touches the Jelly’s tentacles, it automatically becomes poisoned. So if it isn’t already dead, it definitely will be- in no time. First, the small animal will be paralyzed and eventually killed for the Jellyfish to eat it.

Some bigger Jellyfish have stinging threads wrapped up inside, which can be throw out towards prey.

2). The food gets into the mouth through their oral arms

The oral arms close to the mouth will capture its food (prey) and put it into the mouth. The oral arms are much shorter and smaller than the tentacles and can quickly grab plankton, etc. and transport it into the mouth. The Jelly places its mouth right in the center of its prey, and it is directly joined to the stomach. 

The mouth looks more like a tiny hole. It is structured very simple and can only do basic simple tasks like transporting the food into the stomach and shooting out water to propel its body forward. So, its mouth is mainly responsible for moving it around.

3)Jelly’s digestive system

As soon as the plankton lands inside the mouth of the Jellyfish, digestion begins to take its course. (This is a similarity they share with Sea Anemones). The moment the food enters into the Jelly’s mouth, it winds up in the stomach. That is how simplified this system is.

Jelly’s digestive systems are so simple that they have no pancreas, liver, or even intestines!

So how then does it digest the food?

The Jellyfish uses its coelenterons, which has the same function as your stomach and intestines. The coelenteron has several enzymes that help to digest the food. The food is then digested through the stomach-cells, and the leftover is spat out.

 Jellyfish do not have blood or even blood vessels, so there isn’t any actual circulation system.

4) They have no butt

As expected, there should be waste products after digestion has taken place. Surprisingly, the Jellyfish does not have an anus to pass out waste. So the waste from the food that they have digested will have to go out the same way it came in- the mouth!

Water that moves in and out of the Jellyfish i also responsible for removing the waste (feces), thereby creating space for the next bit and piece of food that floats by and gets into the Jelly’s mouth. This water will circulate the food and oxygen inside the Jellyfish to provide the necessities for its survival. 

5). They eat their food really quickly

Jellyfish eat their food at a fast pace since they cannot swim while heavy with food in their stomachs. But this makes a lot of sense since they only eat tiny stuff, so there isn’t much to digest at the end of the day.

What do Jellyfish Eat?

This is largely dependent on the body mass of jellyfish. So let’s begin by categorizing all Jellyfish according to size. This categorization is quite broad, but it will provide you with a clearer perspective of things.

What do the small Jellyfish Eat?

Smaller Jellyfish are carnivorous. Meaning that they feed on every variety of little organisms they find floating around. These things include:

  • Tiny fish
  • Plankton
  • Plants
  • Fish eggs (loaded with proteins!)
  •  many other tiny creatures

In areas with many jellyfish, it can be a huge problem for the smaller fish since the big guys eat every tiny nutritious thing leaving little or nothing for the small fellas. So, the smaller fish will have to seek out food someplace else. But that isn’t much of a problem since the smaller fish are much more intelligent and can quickly figure things out.

 The big Jellies will not go after them as they are not smart enough. They will simply float around in a big mist of unconsciousness.

When many Jellyfish swim together, it is referred to as a “bloom”. A bloom may contain millions of jellyfish, and they are usually a constraint for fishers who often have to wait until the current takes them in another direction.

What do the Big Jellies eat?

Some bigger Jellyfish can capture and kill much bigger organisms using their venomous sting, as we earlier mentioned. It can quickly shoot out its sting whenever an animal triggers it by touching its long tentacles. The moment it is able to capture and kill its prey, it will try to eat it up.

Here are some of the animals that bigger Jellies eat?

  • Plants
  • Lobsters
  • Barnacles
  • Other Jellies
  • Crabs
  • Shrimps
  • Etc.

Additionally, bigger jellyfish can eat other jellyfish. In other words, Jellies are Cannibalistic. But don’t forget that they do not have brains, so they are not aware of what comes in and goes out of their mouth. They have to feed on whatever floats by, to survive. It will eat any organism that swims by, so even if its digestive system is super-simple, it can eat a wide variety of food. Quite impressive!

Who eats the Jellies?

The Jellyfish are always in danger of being captured and eaten by animals like:

  • Sea Turtles
  • Sunfish
  • Spadefish
  • Other Jellyfish
  • Human beings!

As we mentioned earlier, humans consider Jellies an excellent meal. A good example is the “Cannonball Jellyfish” which is often served at luxury restaurants, particularly Asia, where the seafood business thrives most.

For the U.S State of Georgia, Jellies are of excellent export value. They are also being sold to distributors across Thailand, China, and Japan, Where they will end up in plates and bellies. Jellies are usually dried and packaged before being shipped off.          

How many known species of Jellyfish exist or  How many Jellyfish types are there?

There are over 200 known species of Jellyfish. Some are big, others, small. The majority of them are not dangerous to humans. However, touching their tentacles may still irritate.