Fish Facts

We are surrounded by so many types of fish in both salt and freshwater.

They have developed into a variety that we use as a food source and for their beauty in our aquariums.

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Fish Facts for Kids

  • There are over 33,000 varieties of fish in the world
  • Fish are cold-blooded and they cannot control their own body temperature.
  • They have a good sense of sight, touch, and taste.
  • Fish have spines that are surrounded by cartilage and bone and are ‘vertebrate’ animals.
  • Fish breathe through their gills that take in the water where they extract oxygen
  • They have developed a lot of methods to survive. Some use camouflage as a way to hide in reefs, the ocean floor, and rocks.
  • It is believed that fish can actually feel pain.

What are some characteristics of fish?

Fish have gills that allow them to breathe underwater. Fish have spines and a skeleton that is surrounded by cartilage and bone and are ‘vertebrate.’

There are approximately 33,000 different species of fish in the world that live in many diverse environments. They live in oceans, rivers, ponds, and streams

Some live in saltwater, and others live in freshwater.

The female can lay up to 250 egg at a time

They come in a variety of colors. Some can blend into the environment to avoid prey

What do fish like to eat?

As I’m sure you know there are so many different types of fish so not everything they eat is the same.

Some fish are omnivores and they will feed on other marine animals like worms, smaller fish and crustaceans.

Some fish will eat plant matter and small organisms like algae.

Some fish are carnivorous and eat other fish like Krill, Shrimp, crabs and Squid.

At home, you can feed your fish an assortment of things

  • Flake Fish Food
  • Pelleted Fish Food
  • Freeze Dried, Frozen, and Live Foods

Where do Fish live?

You will find fish in most bodies of water. This includes ponds, rivers, lakes, coral reef the ocean, and even streams.

Fish live in fresh was and saltwater.

In the ocean, fish live in coral reefs and even the deepest depths.

How Do Fish Defend Themselves?

Fish have several ways and techniques to help protect themselves. Many will use their color to help camouflage themselves from any predators.

Many different types of fish will form a school with hundreds and even thousands of similar fish to protect themselves in a large group. They have many other senses, and some will use their spines and even venom for defense.


Because they come in many colors, this can play a pivotal role in ensuring that they can camouflage themselves. It has two advantages. The first is that it helps them blend into their environment so that a predator will not find them in. The second is it allows them to pray on other fish without being seen.


Another interesting form of defense that fishes use to help avoid predators is schooling. I’m sure you’ve seen this before where you see several fish swim together. Schools of fish can be absolutely massive and have thousands upon thousands to help protect each other.

Any predators that come across the school can be totally confused simply because of the sheer numbers. By keeping close together, the fish can move in waves and synchronize, which can make it quite difficult for a predator to get one fish.

It’s a really interesting defense method and is usually used by fish who are of the same breed and consistent in the same size.

Staying Alone

Being part of the school is a great means of defense for fish. It’s especially helpful for smaller fish as they can be quite vulnerable. However, being by yourself and swimming alone is also a superb method of defense. Being a solo fish can make it easier to hide and keep out of sight. Many fish adopt this survival mode to help keep a low profile away from predators.

You’ll find many solitary fish living in vegetation and being able to hide under stones. Many will stay in these positions during the daytime and only come out at night. They can blend in well and camouflage themselves with their coloring.

Larger fish are at a little of a disadvantage as this really is more suitable for smaller fish. The smaller fish can hide in small rock crevices, coral, sponges. This is great for staying safely away from predators.


With many defenses available like camouflage and schooling, fish also rely on their senses to help survive being eaten by a predator.

They have amazing senses, which include sound and sight.

When fish are schooling, they rely on sound and sight to make sure that they stay together. They are moving as one large fish to help deter predators. They rely on their sight to help keep the school’s cohesion.

Sound is also a key element would schooling fishes simply because when they are schooling, denies in the water helps to alert them, and they can swim accordingly.

They also have other senses throughout the body on the head on both sides of their body. This lateral line system allows them to detect movement and vibrations in the water around them.

Some species of fish have developed ways to swim fast.

Tuna can swim up to 70 mph (43 mph)

  • The fish brain, in relation to its body size, is rather small when you compare it to the brain size of other animals.
  • The body of most fish is covered in scales. This helps them move more quickly through the water. Some fish have a slime layer over the scales that helps with speed and offers less ‘drag’.
  • Some fish have developed a relationship with other fish so that they are ‘cleaner fish’. They eat the dead skin and parasites from other fish without being eaten themselves.

While we call jellyfish, starfish, and crayfish ‘fish’, they are not really fish.

  • It is currently estimated that there are over one thousand species of fish that are being threatened by extinction.
  • Most species of fish lay eggs to reproduce. Some fish, such as the shark, actually give birth to live babies.

The mudskipper fish has the ability to spend half of its time outside of the water and actually use its fins to ‘walk’ on land.

It breathes out of water in two ways: through a portable water supply that is maintained in its gill chambers and also through wet skin pores.

  • Humans have 7,000 taste buds, a catfish has 27,000
  • Many of the brands of lipsticks on the market contain fish scales
  • Seahorses are a type of fish and are the only species that swim upright.
  • Sharks are one of the most unusual species of fish in many ways. They are the only ones that have eyelids.

More Fish Facts

  • Most of the fish that we know about have a skeleton that is made from bone.
  • Some fish actually help each other by removing parasites and dead skin from their scales.
  • Fish such as halibut and cod live in saltwater. Freshwater fish such as catfish and trout can be found in rivers and lakes.
  • Did you know that the great whale shark can grow to 50 feet long?
  • Somebody who studies fish is called an ichthyologist.
  • In some species of fish, it is difficult to tell which are male and female because there is no visible tell-tale signs. But, in some species the male and the female shaped differently.
  • Maybe you sometimes wonder how fish can navigate in dark and muddy waters well fish have a special organ called the lateral line which is similar to radar and helps them to navigate.
  • Fish can eat a variety of different things like other fish, algae, insects, turtles, fish eggs, mollusks, and even water birds.
  • Fish breathe by using a special organ called gills.
  • Cod is one of the top five fish people in Europe eat.
  • There are many different types of salmon fish and they have funny names like a chum, pink, chinook, sockeye, and coho.
  • A dogfish is a type of shark that likes to eat small fish, squid, shrimp, and even craps.
  • Did you know that a lobster can outgrow its shell? In actually can and does so every year, every year it will grow a new shell.