Fish belong to a category of creatures called aquatic vertebrates. Fish are different in colour and size; there are small and big fish. They are also different from all the other animals because they have gills and fins. Besides, they only live in water.
All fish have skeletons whether made of bone or cartilage. Sharks are of the kind that has a skeleton made of cartilage. Fish are also cold-blooded except for the Tuna family and the Mackerel shark family. It is believed that there are around 25.000 species of fish however there is a lot more to be discovered.
Jawless, cartilaginous, and bony fish are the three main types of fish. The lamprey eel is one of the jawless fish while the blue marlin is one of the bony fish. Although whales, dolphins, octopuses, and jellyfish live in water, they are not classified as fish.
What is a School of Fish?
A school of fish can be defined as a shoal of fish swimming in the same direction. Fish swim in groups to protect themselves against enemies. They unify their movements and positions. Fish schooling escapes any predator because they look so big.
It is easier for a school of fish to find food; there are many eyes and noses to find out where food is. Fish schooling also gives the fish the chance to keep their eggs away from predators. Not only do small fish swim in schools, but also fierce fish do. For example, Piranha fish lives in huge schools.
Tuna, herring and anchovy, spend all of their life swimming in schools of fish or a shoal. If they get separated from the school, they feel anxious. On the other hand, Atlantic cod swims in schools a few times in their life.
Schools of fish have different shapes according to the species of fish and the purpose of schooling as well. Long thin lines, squares or ovals or amoeboid shapes are some examples of the shapes. forage fish form their schools away from the bottom and in open water, that’s why they are pelagic fish.
Herring is one of the amazing schooling fish; they connect to other schooling fish while migrating from one place to another. It is estimated that about three billion fish are found in one school. They also have a good sense of hearing which allow reacting fast to any predator.
Let’s check the fish names that swim in a school:
- Minnow fish
- Some species of the sunfish family
A School of Fish Vs a Shoal of Fish
|A Shoal of Fish||A School of Fish|
|It is a kind of unified behaviour by fish.||It is a kind of unified behaviour by fish.|
|It is a group of fish swimming together for social reasons.||It is a group of fish swimming together in the same direction, all together at the same speed.|
|It can consist of the same kind of fish or different kinds of fish.||It can consist of the same kind of fish or different kinds of fish.|
|25% of fish shoal all their lives while 50% of fish shoal part of their lives.||Some Fish Spend most of their lives schooling like Tuna.|
|There is no leader.||There is no leader.|
|It needs a large open space to swim.||It needs a large open space to swim.|
|It is a defensive way against predators.||It is a defensive way against predators.|
|It becomes easier to find food.||It becomes easier to find food.|
|It swims faster than alone fish.||It swims faster than alone fish.|
|The largest shoals are usually formed during migration.||The largest schools are usually formed during migration.|
|Predatory fish can form a shoal.||Predatory fish can form a shoal.|
|It uses different techniques for defense like confusion effect, many-eyes effect, and dilution effect.||It uses different techniques for defense like confusion effect, many-eyes effect, and dilution effect.|
|The minimum number of fish in a shoal is from 4 to 6.||The minimum number of fish in a school is from 4 to 6.|
|It consists of fish of different sizes and ages.||It consists of fish of the same age and almost the same size.|
Different Species, Different Group Names
Some species when they swim in groups have specific names. They’re not referred to as a shoal of fish or school of fish. Let’s view some of these species and their unique names along with their picture:
- A group of Trout is called hover.
- A group of Betta (female) is called a sorority.
- A group of Swordfish is called flotilla.
- A group of Dogfish is called a troop.
- A group of Goldfish is called a glint.
- A group of Eel is referred to as a swarm.
- A group of Cod is called a school or shoal.
- A group of Mackerel is called a shoal.
- A group of Shrimp is called a troop.
- A group of Sardine is called a family.
- A group of Tuna is called a school or afloat.
Clumped dispersion is one of the three distribution patterns for individuals. These patterns are uniform, random, or clumped. Clumped dispersion happens in animals that live in groups. A school of fish is an example of clumped dispersion.
What is a School of Baby Fish Called?
A baby fish is called a fry. However, there’s no specific name for a group of baby fish. It is still called a shoal of fish or a school of fish. Some people mistake tadpoles with fry. Tadpoles refer to baby amphibians. As well, guppies refer to babies of some species that belong to the swordtail family.
What about Jelly Fish?
Jellyfish are not considered a type of fish. They don’t have a backbone or gills. They absorb oxygen from the water. They can be of different colours like pink, yellow, blue and purple. They are called Jellyfish because their bodies are jelly-like.
There are more than 2.000 types of Jellyfish all over the world. They live in oceans. Three names refer to a group of Jellyfish. These names are as follows: bloom, smack and swarm.
Some Interesting Facts about Fish
- Fish have spines, fins and gills. They absorb oxygen from the water.
- Fish are covered in scales.
- Fish lay eggs
- Some fish eat plants while others eat only meat depending on the species.
- Some fish use camouflage to be protected from predators.
- There are over 30.000 kinds of fish.
- Fish can live in deep and shallow waters.
- Some types of fish can be kept at home in a fishbowl or tank.
- Fish live in both freshwater and saltwater.
- Fish are of various colours and sizes too.
- Jellyfish and Starfish are not considered as types of fish because they don’t have a spine and they breathe in water.
- Fins help fish to swim.
- Acoustic sounds are a way of communication among fish.
- Fish are considered cold-blooded creatures because their body temperature can change according to their surroundings.
- Fish can see, taste and feel.
- Fish can lay around 250 eggs at a time.
- Schooling and camouflage are some of the techniques fish use to protect themselves against predators.
- A large number of species are threatened by extinction.
- Seahorse is the only species that can swim upright.
- The lateral line is an orange that helps fish navigate.
- Cleaner fish help other fish to remove the dead skin and parasites from their scales.
- Most fish don’t blink because they don’t have eyelids.
- Tuna is one of the fastest species of fish. They can swim up to 47 mph.
- Sailfish can swim 68 mph while Marline can swim up to 50 mph.
- A whale shark is the biggest fish on planet Earth. It can weigh 18.7 tones.
- It is believed that fish lived on Earth before dinosaurs about 500 million years ago.
- Salmon migrate every year to lay eggs.
- The shape of the fish mouths differs from one species to another.
- The fish teeth vary according to their diet.
- Pufferfish is a poisonous type of fish because it contains a toxin called tetrodotoxin.
- Tiny goby is considered the smallest fish.
- Up to 51% of fish live in freshwater.
It is believed that Fish were there on Earth even before dinosaurs, around 500 million years ago. There are over 30.000 species of fish. They live in shallow water, deep water, saltwater or freshwater. Fish swim in shoals. When a shoal swims in the same direction, it is called a school of fish. A school of fish includes fish of the same species and almost the same size.
Let’s Check Your Information:
- Fish use _________ to breathe underwater.
a- lungs b- mouth c- gills
- ___________ help fish to balance and swim.
a- gills b- scales c- fins
- Fish can live in various types of habitat, but it is necessary to have _______
a- mud b- sand c- water
- A_________ refers to a group of fish.
a- group b- shoal c- bulk
- A shoal that is swimming in the same direction is called a______.
a- school of fish b- a group of fish
- Schooling can protect fish from ________.
a- cold weather b- predators
- _______ is a technique used to protect themselves from predators depending on their colours.
a- shoal b- camouflage
- Fish do not have_______.
a- lungs b- mouths c- spines
- Fish do not blink because they do not have _______.
a- eyelashes b- eyelids
- __________ is the fastest fish.
a- Tuna b- Sailfish