Jellyfish are amazing sea animals that look like floating umbrellas with long, wiggly arms. They’ve been swimming in the oceans for millions of years and come in many shapes, sizes, and colors. Even though they don’t have brains or bones, jellyfish can still move, eat, and glow in the dark!
Watch a Jellyfish in Action!
See how a jellyfish floats and swims through the water like a balloon with tentacles. These gentle creatures move in a magical, wavy way that’s fun to watch.
What is a Jellyfish?
Jellyfish are soft-bodied sea animals that live in oceans all around the world. They have see-through bodies and use their tentacles to catch food.
- Jellyfish are not actually fish
- They have no bones, no brain, and no heart
- They use their tentacles to sting and catch food
- Some jellyfish glow in the dark!
Where do Jellyfish live?
Jellyfish live in oceans all over the world. Some stay near the shore, and others live deep in the sea.
- Found in warm and cold oceans
- Some jellyfish float near the surface of the water
- Others live deep down where it’s very dark
What do Jellyfish eat?
Jellyfish are carnivores, which means they eat other animals like small fish and sea creatures.
- Eat tiny fish and shrimp
- Use stingers to catch their food
- Some eat plankton (tiny ocean plants and animals)
How big is a Jellyfish?
Jellyfish come in many sizes. Some are as small as a button, and others can be as big as a car!
- Small jellyfish can be just 1 inch (2.5 cm) wide
- Big jellyfish, like the lion’s mane, can be over 6 feet (1.8 meters) wide with tentacles up to 100 feet (30 meters) long!
What sound do Jellyfish make?
Jellyfish don’t make any sounds. They move quietly through the water without making a peep.
Cool Jellyfish Facts
Jellyfish are full of fun surprises! Here are some jellyfish facts that kids love:
- Jellyfish have been on Earth for over 500 million years
- Some jellyfish glow in the dark using bioluminescence
- They don’t have eyes, but can still sense light
- Some jellyfish can clone themselves
- The box jellyfish is one of the most dangerous
- One jellyfish, called the immortal jellyfish, can live forever!
- Jellyfish move by pulsing their bell-shaped bodies
Printables and coloring fun
Have fun learning more about jellyfish with these printable and online activities!
Jellyfish in the eco-system
Jellyfish are an important part of the ocean food chain. They help keep ocean life balanced.
- They provide food for sea turtles and large fish
- They help control the number of small fish and plankton
- Most jellyfish are not endangered, but too many can be a problem
- Some jellyfish blooms happen when the ocean gets too warm or polluted
Ask a grown-up to help you learn more
Want to learn more about jellyfish? Ask a grown-up to visit these great websites with you:
- National Geographic Kids – Jellyfish
- Fascinating facts about jellyfish
- Jellyfish | Official SEA LIFE Website
Fun questions about Jellyfish
No, jellyfish do not have brains! They use nerves and special cells to sense things around them.
No, jellyfish swim very slowly. They mostly drift with ocean currents.
Jellyfish sting to catch food and protect themselves from danger.
No, jellyfish are not real fish. They are invertebrates, which means no bones!
Most jellyfish live a few months, but some can live for years. One kind may live forever!
Yes, jellyfish rest at night in a quiet, sleepy way even though they don’t have a brain.
Baby jellyfish are tiny and look like little flowers before they grow into the jelly shape.
Some jellyfish stings can hurt people, but most are not dangerous.
Some jellyfish glow in the dark to scare predators or attract food. This is called bioluminescence.
No, most jellyfish are not dangerous to people. Only a few kinds can cause strong stings.
Ways to donate and support Jellyfish
You can help protect jellyfish by keeping the oceans clean and supporting ocean groups that care for sea animals. Every little action helps the sea stay healthy!
Sources: Wikipedia, Live Science, Creative Commons, Britannica.com and Freesound.org
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