Koalas move slowly and relaxed while clinging to trees.

Just looking at their adorable appearance can heal you.

Did you know that koalas sometimes run on the ground?

Let’s explore the secrets of koalas that are still hidden together!



~ Basic information. ~

Diprotodontia-Phascolarctidae-Koala genus.

Length:65~8cm weight:4〜15kg.

Koalas are concentrated in the eastern part of Australia.

The forests where koalas live are full of eucalyptus trees, which are their main food.

It is easy to distinguish between male and female koalas.

Male koalas have a part called a scent gland on their chest that emits an odor.

They mark trees by rubbing the gland on them, so it is easy to tell because the chest area of male koalas is brown.

Koalas are cute in appearance but they are creatures with a high sense of territory.

Each koala has its own “living area”.

The size of the living area is determined by age, sex, and status, and males with higher status can have larger territories.

Basically, koalas act alone in their own living areas, but only mother koalas live together with their children until they become independent.


Even baby koalas are kicked out of their mother’s living area when they are around 1-2 years old.

This is the timing for baby koalas to become independent.

They have to go far away and look for a new living area with their own power.



Koala’s Q&A.

Why do koalas only eat eucalyptus?


Actually, eucalyptus leaves contain a poison called cyanide.

The poison is acquired by eucalyptus itself to prevent animals and insects from eating it.

Why can koalas eat eucalyptus leaves even though they contain poison?

That’s because they have many microorganisms in their intestines that break down the poison.

They slowly break down the poison over time in their 2-meter-long intestines.

Can other animals break down and eat the poison?

No other animals besides koalas can break down and eat the poison.

It is surprisingly important for koalas that their food does not overlap with other animals.

This is because koalas are not strong creatures and will lose out if they compete with other animals for food.

They cannot survive in the harsh wilderness if they do so.

Not having to fight with other animals over food is important.

Even if there is poison, koalas have learned that monopolizing eucalyptus and continuing to eat it is one of the necessary means of survival.

Why is a koala’s nose big?

Koalas have poor eyesight, so their noses have developed instead.

The koala’s nose has the role of distinguishing two smells.


The first role is that they can distinguish the amount of poison contained in eucalyptus.

Eucalyptus, which is their main food, contains poison, and the amount of poison varies depending on the tree.
Even koalas that are resistant to poison try to choose trees with less poison.

They also use their big noses to find their favorite taste.

The second role is that they can distinguish the smell of other koalas on the tree.

Koalas mark the tree they live on with their scent.
Marking is the act of rubbing and emitting odor from the scent gland to claim one’s own.

Since only one koala can live on a single eucalyptus tree, it makes sure to check if it is not marked by other koalas.

The koala’s nose has grown larger for these two roles.

Why do koalas hardly move?

When you think about the life of a koala, don’t you imagine them living a life of sleeping and eating on trees and hardly moving?

It is said that koalas sleep an average of 18-20 hours a day.


Is there a reason why they spend so much time sleeping?

The answer lies in their staple food, eucalyptus.

Eucalyptus, which koalas eat as their staple food, contains hard-to-digest ingredients such as tannins and oils and poisons.

It takes time to digest them, so they consume a lot of energy.

Koalas recover from the energy they consume by sleeping and taking breaks, not just by not moving around.

Do koalas sometimes walk on the ground?

When koalas move to other trees, they sometimes walk on the ground and sometimes jump and get on.

Actually, walking on the ground is the most vulnerable time for koalas.

Koalas can also run, but it is said that they run at a speed of about 20-30 kilometers per hour.


Because they cannot run fast, more than 4,000 koalas die each year from being attacked by dogs or hit by cars.

Instead, they can jump up to 2 meters without a run-up.

You can see that jumping is safer.

How do baby koalas grow?

When a mother koala enters the breeding season and becomes pregnant, she gives birth in just 35 days.

As it takes ten months and ten days for a human to give birth, we can see that koalas give birth very quickly.

The size of a newborn baby is about 2 cm when it is born with a small body.

Although the eyes and ears are not yet developed, it has four functions: smell, touch, sense of direction, and strong front legs.

Using these four functions, a newborn baby can reach the bag on its mother’s belly with its own power.


There are two breasts in the pouch, so they grow by drinking only mother’s milk for 6-7 months after birth.

After that, they start eating something called “pap” from their mother, not just milk.

What is “pap”?

Pap is a soft feces made in the mother’s intestine.

This soft feces contains microorganisms that live in the mother’s intestine, so baby koalas can also cope with eucalyptus poison.

They grow up until they can ride on their mother’s back and eat eucalyptus.

At around 1-2 years old, they start looking for their own living space.

Do you know the vulnerable species that contain koalas?

Koalas are included in the “vulnerable species”.

Do you know what an vulnerable species is?

“Vulnerable species” is one of the categories included in the International Union for Conservation of Nature (IUCN) Red List.

Vulnerable species refers to animals that are at risk of being included in the critically vulnerable species category due to environmental deterioration.

Koalas suffered greatly in the forest fires that occurred in Australia in 2019.

The exact number is unknown, but it is possible that thousands of koalas died.

Also, their habitat and main food source, eucalyptus trees, were burned down.


There are hundreds of species of eucalyptus, but only a few are edible for koalas.

The shortage of eucalyptus due to the fires is a big problem for koalas.

Koalas lost a lot in this fire and have become closer to being critically endangered.



Type of koala.



Australian Koala Foundation




BBC News 豪ニューサウスウェールズ州のコアラ、2050年までに絶滅の恐れもhttps://www.bbc.com/japanese/53247907