Animal Group

Fish Facts For Kids

Fish are cold-blooded animals that live in water their whole lives! They breathe through gills and use fins to swim. From tiny minnows to huge whale sharks, fish come in every color and size you can imagine.

Quick Fish Facts

How many kinds?: Over 34,000 known species of fish
Body covering: Scales (a few have smooth skin)
Body temperature: Cold-blooded (a few like tuna can warm parts of their body)
Babies: Most hatch from eggs called roe
Breathing: Gills pull oxygen out of the water
Smallest: Paedocypris fish, smaller than a fingernail
Largest: Whale shark, can be 40 feet long

Tropical Fish: The Colorful Reef Dwellers

Tropical fish live in warm ocean water near coral reefs. They are some of the most colorful animals on Earth! Their bright stripes and patterns help them hide among the coral or send messages to other fish.

Featured animals: Clownfish, Angelfish, Parrotfish, Butterflyfish

Freshwater Fish: The River and Lake Fish

Freshwater fish live in rivers, lakes, ponds, and streams. Most freshwater fish cannot live in salty ocean water. People love to catch freshwater fish for fun and for food.

Featured animals: Bass, Trout, Catfish, Salmon, Goldfish

Saltwater Fish: The Ocean Swimmers

Saltwater fish live in oceans and seas. They have special body parts that handle salty water. Many saltwater fish travel long distances across the ocean every year.

Featured animals: Tuna, Cod, Mackerel, Swordfish

Sharks and Rays: The Cartilage Fish

Sharks and rays have skeletons made of bendy cartilage, not bone. Sharks have rows of sharp teeth that get replaced when they break. Most sharks are not dangerous to people.

Featured animals: Sharks, Great White Sharks, Hammerhead Sharks, Stingrays

Cool Facts About Fish!

Some fish can climb trees! Mudskippers can leave the water and use their fins to climb up roots and branches.
Seahorses are fish! They look strange, but seahorses are real fish. And dad seahorses carry the babies in a special pouch!
Flying fish actually glide! Flying fish leap out of the water and glide up to 600 feet on their wing-like fins.
Some fish make their own light! Deep-sea anglerfish dangle a glowing lure to attract prey in the dark ocean depths.
Goldfish have great memories! Even though people say goldfish forget everything in 3 seconds, they actually remember things for months.

Fish Questions Kids Ask

How do fish breathe underwater?

Fish have gills on the sides of their heads. Water flows through their mouths and out their gills. The gills take oxygen out of the water and put it into the fish's blood.

Do fish sleep?

Yes, but not like we do! Fish rest with their eyes open (they have no eyelids). Some fish hide in coral or mud while resting. Some shark species must keep swimming to keep breathing.

How do fish stay floating?

Most fish have a special bag inside their bodies called a swim bladder. They fill it with air or empty it to go up or down. Sharks do not have one; they sink if they stop swimming!

Are dolphins fish?

No! Dolphins are mammals. They breathe air, are warm-blooded, and feed their babies milk. Fish breathe underwater through gills and are cold-blooded.

What is the most dangerous fish?

The stonefish! Stonefish look like rocks on the ocean floor. They have venomous spines that can make a person very sick if you step on one.