Fish Facts

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

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

Fish Facts for Kids

  • Fish have spines that are surrounded by cartilage and bone and are ‘vertebrate’ animals.
  • Fish breathe through their gills that take in water where they extract oxygen
  • There are many species of fish. It is estimated that there are about 30,000 varieties.
  • Fish have developed a lot of methods to survive. Some use camouflage as a way to hide in reefs, the ocean floor and rocks.
  • Did you know that there are over 30,000 different species of fish.
  • Fish are cold-blooded and they cannot control their own body temperature.
  • It is believed that fish can actually feel pain.
  • They have a good sense of sight, touch and taste.
  • Most of the fish that we know about have a skeleton which is made from bone. However, sharks have a skeleton made from cartilage.
  • Some fish actually help each other by removing parasites and dead skin from their scales.
  • Fish such as halibut and cod live in salt water. 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.
  • 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 a 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 chum, pink,chinook, sockeye and coho.
  • A dogfish is a type of shark 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.


Some species of fish have developed ways to swim fast.

Tuna is a species that 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 are 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 cat fish 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 swims upright.
  • Sharks are one of the most unusual species of fish in many ways. They are the only ones that have eyelids.

What do fish feed on?

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.

Some fish are carnivorous and eat other fish.

At home, fish can eat

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

Where do they live?

You will find fish in most bodies of water. This includes ponds, rivers, lakes, 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.