Koala Facts Koala Bear

Koala sleeping in a tree

Photo: Koala sleeping in a tree

The koala is a small tree-dwelling marsupial that lives in Australia. With its fluffy fur, prominent black nose, large furry ears and cute and cuddly appearance, it is one of the most recognizable animals in the world. The koalas spend most of their time in trees, sleeping 18 to 22 hours a day and feeding mainly at night. It is a fairly harmless animal. However, if provoked, it can scratch and bite in self-defence. Koala is pronounced "co-aa-laa".


Are Koalas Bears?

Teady Bear

Koalas are not bears! They are herbivorous (plant eating) marsupial mammals. Bears, on the other hand, are omnivorous (eat plants and animals) placental mammals. When European explorers first came to Australia and saw koalas, they thought these animals looked like the bears they knew back home. So they named them "koala bears". People still refer to them as koala bears because they look cute and cuddly, like teddy bears.


Koala Description

Koala climbing a tree

Photo: Koala climbing a tree

Koalas are 70–90 cm (27-35 in) in length and weigh 4–15 kg (9-33lbs). Their fur range in colour from grey to brown. They have large oval-shaped furry ears, small forward-facing eyes, big noses, and no tails. The fur on their chests is usually white or yellowish-grey. Male koalas also have a moist, dark, hairless patch on the middle of their chests with a scent-producing gland. They rub the scent from this gland on tree trunks to mark their territories.

Koalas vary in size and fur colour depending on where they live in Australia. Those found in the warmer climates of Queensland and northern New South Wales are lighter in colour and significantly smaller than those found to the south in Victoria, where the weather is much colder.

Koala's foot with padding, toes and claws

Photo: Koala's foot with big toe and fused toes

The koala has long, powerful arms and legs with clawed hands and feet with rough padded palms and soles suitable for climbing. The koala’s hands have two opposable thumbs and three fingers to better grasp tree trunks and branches. Also, each koala has a unique fingerprint that differs from every other koala. Because the koala is a tree-dwelling animal, its arms and legs are very similar in design and function to primates, such as monkeys.

The koala has rough padded feet with five toes. Its big toes are opposable, broad and do not have a claw. The second and third toes are fused together but have two separate toenails. Besides assisting in climbing, the koala uses the toenails of the joined toes as a convenient comb to groom itself with.

The koala has a round fluffy light grey or white bottom (posterior) covered in thick fur, with a slightly darker patch surrounding its anus. Hidden beneath this fur is thick cartilaginous padding that acts as comfortable cushion on which it sits while resting or sleeping. As a result of its sitting behaviour, the koala doesn't have a visible external tail. However, the skeleton of the koala shows presence of a vestigial tail now hidden inside its body. The koala shares these characteristics with its closest relative, the wombat.

The koala sleeps 18-20 hours a day to conserve energy. The koala’s diet is so low in nutrients and hard to digest that the koala gets very little energy from its food. So it conserves what little it has by sleeping most of the day.


Koala Brain Are Koalas Dumb?

Despite its large head, the koala has a small and simple brain that makes up only 0.2% of its body weight and occupies only 61% of its brain cavity,  which is much less than most mammals of comparable size. This lack of complexity in its brain contributes to the koala's lower intelligence. A classic example is when given eucalyptus leaves in a bowl; the koala doesn't recognise them as food even though it typically loves eating these leaves from a tree branch! Similarly, koalas do not understand how rain affects them and stay in the rain without understanding why it is getting wet.

There is an evolutionary reason for its tiny brain. It lives in an environment with abundant food and few predators, making large energy-intensive brains unnecessary. Hence, over millions of years, evolution helped conserve energy by reducing the size and complexity of the koala's brain. So the koala may not be the smartest kid on the block, but its brain is big enough to meet the needs of its laid-back lifestyle.


Koala Sound What Does a Koala Sound Like?

Koala making a bellowing sound

Photo: Koala bellowing in a tree

Koalas are usually quiet animals. However, they are capable of loud vocalizations, referred to as bellowing. While both male and female koalas can make these sounds, the male usually bellows to attract a mate. In addition, the males advertise their size by changing the resonance of their bellows. Larger males have lower, more closely spaced bellows that are more attractive to females than those produced by smaller males. Koalas also make other sounds, including squeaks, screams, and snarls. When stressed or frightened, a koala may cry like a baby screaming. This behaviour is often accompanied by shaking.


Koala Climbing, Walking & Running How Fast Can a Koala Gallop?

Because of their energy-conserving habits, koalas usually move slowly. But when climbing a tree up from the ground, they will bound with their arms reaching out to grab the trunk while their legs push off behind. This momentary energy-intensive frog leap enables the koala to gain elevation and safety quickly. While in the tree, koalas move along slowly using all four limbs. When they climb down a tree, they back down cautiously and move one limb at a time while gripping on with all three other paws. On the ground, the koala’s gait is slow and awkward. But if scared or alarmed, they can gallop at up to 30kph (18 mph) towards the nearest tree for safety!


Koala Habitat Where Do Koalas Live?

Koala habitat and distribution map

Photo: Koala habitat map

Koalas live primarily in eucalyptus trees in Australia's temperate, tropical and sub-tropical forests and woodlands. Koalas are arboreal, prefer to live alone and rarely come down to the ground except to travel from one tree to another. Each koala marks out a territory consisting of several trees, called a home range, and rarely ventures out of it. Within its home range, a koala will mark its favourite feeding trees, referred to as its home trees and will vigorously defend these home trees aggressively.

Koala kicked out of Tree

Young koala crying after being kicked out of a tree by an adult
Watch Video

While home ranges may overlap, a koala will not venture onto the home trees of another koala (see video). The size of the home range depends on the density and nutritional value of trees in the area. It may vary from 135 hectares in Queensland to as little as one hectare in Victoria, where the vegetation is lusher. The quality of the trees in a given area determines the number of koalas that can effectively there. This is called the carrying capacity of the forest.


Koala Diet What do Koalas Eat?

Koala eating gum leaves

Photo: Koala feeding on eucalyptus leaves

Koalas eat the leaves of just 35 types of eucalyptus trees. Occasionally, they may also eat the leaves of a few other plants. The koala feeds mainly at night, consuming approximately 400gm (14oz) of leaves daily. Koalas are leaf-eating animals called folivores.

Eucalyptus leaves contain tannins, phenols, cyanogenic glycosides and essential oils that are highly poisonous to most animals, hard to digest, and very low in nutrition. However, the koala's ability to eat these leaves gives it access to a widely available food source that most other animals cannot eat.

The koala uses its highly sensitive nose to select only those leaves that are high in nitrogen and low in poisonous tannins and essential oils. Then, it nips the leaves with its front incisor teeth and chops them with its sharp molar teeth before swallowing. It also has cheek pouches for storing extra leaves before chewing. The koala requires very little water and usually gets all the liquid it needs from the leaves it eats. However, it may occasionally supplement this with water from tree hollows and other sources if necessary.

The koala's digestive system is specially adapted to detoxify the poisonous chemicals in its food. It has a small stomach but a large cecum, nearly 1.3 meters long. Its cecum is home to 45 different species of bacteria, some of which are excellent at neutralising toxins. Food is digested for up to 22 hours to break down and extract as many nutrients as possible.

The koala poops all day long, even while sleeping. It produces up to 360 dark green olive-shaped faecal pellets with a strong eucalyptus smell.

For more information, here is an excellent scientific paper on the koala's diet.


Koala Reproduction & Life Cycle Koala Mating, Pregnancy, Birth, Pouch

Koala baby joey crawling to mother's pouch

Photo: Newborn joey finding its way to pouch

Koala reproduction involves the male koala climbing onto the female's back and mating with her. After a gestation period of around 35 days, the female will give birth to a baby called a joey. At birth, the baby joey is about the size of a jellybean, blind, and has no ears, with tiny stumpy limbs. Once it has exited the mother's birth canal, the joey uses its sense of smell and strong arms to crawl up to its mother's abdomen and into the safety of her pouch. Once inside the mother's pouch, it attaches itself to a nipple and develops into a viable koala.

koala mother with baby on its back

Photo: Koala mother with joey on its back

At about six months, the joe begins feeding on a runny jelly-like substance passed through the mother’s rectum. This pap contains essential gut flora micro-organisms that the joey will need to transition from weaning to leaf-eating. The joey then starts to pop its head out of the pouch and nip on eucalyptus leaves as its mother climbs about the trees. As it grows larger, the joey begins clinging onto the mother's underbelly. When this becomes too difficult, it rides on its mother's back, feeding on leaves as it travels with its mother. Finally, in about the twelfth month, the joey is weaned from its mother and sets out on its own.


Are Koalas Endangered? Koala Threats and Predators

In February 2022, the Australian government declared that the koala was endangered. It is estimated that less than 100,000 koalas are left in the wild. Some estimates put their number as low as 43,000 animals. While koalas have native predators such as dingoes, goannas, and large predatory birds, they face their biggest threat from humans. Listed below are some key contributors to the decline in koala numbers.

koala being cruelly removed from tree

Habitat lose is the major reason for the koala being endangered. The koala population has declined drastically due to the destruction, fragmentation, and loss of their forest habitats. Nearly 80% of the koala's habitat has already disappeared. Most of this deforestation has resulted from human activity such as logging, farming, and suburban sprawl. (Photo: See a frightened koala callously dislodged from a tree).

Koala stuck to front of car after an accident

Motor vehicle strikes and dog attacks account for as many as 4,000 koala fatalities yearly While safe in their trees, koalas are vulnerable when they are on the ground walking from one feeding tree to another.
(Photo: This lucky koala had an 80kph impact with a car and survived unscathed).

Koala being rescued and feed water after a bushfire

Forest fires in Australia are fast and burn intensely. The koala is too slow to run away from these fires and usually seeks shelter by climbing to the top of a tree. Many perish in bushfires. Sam the Koala (photo) captivated the hearts of millions of people when a fire-fighter rescued her after the Black Saturday bushfires in 2009. Unfortunately, Sam was euthanized later that year because she was suffering from incurable cysts caused by the disease Chlamydia.

Sick koala being given medicine

Chlamydia is common in koalas and is a serious threat to the koala population. Chlamydia cause Conjunctivitis which may result in blindness, urinary and reproductive tract infections (which lead to infertility) and pneumonia.


How did the Koala Get its Name?

The word 'koala' is pronounced "co-aa-laa". It is derived from the word gula from the Dharug language of the Yuin-Kuric aboriginal people. The koala's scientific name, phascolarctos cinereus, loosely translates to "ash grey pouched bear". There is no collective noun for a group of koalas. Some names in common usage are 'koala colonies' or 'koala populations'. A very creative person suggested that we should call them a "cling" of koalas.


25 Koala Facts

  1. koalas are tree-dwelling Australian marsupials.
  2. They live in eucalyptus trees on the eastern seaboard of Australia.
  3. Koalas in warmer climates are small and lighter than those in colder climates.
  4. The koala has a padded bottom because it sits so much. Because it sits so much , the koala doesn't have a tail.
  5. The koala has only 11 pairs of ribs. Most most mammals have 13.
  6. They have unique fingerprints, like humans.
  7. Koalas sleep 18-22 hours a day.
  8. To conserve energy, a koala moves slowly and feeds mainly at night.
  9. It is sometimes called a Koala Bear. But it is not a bear at all. It is a marsupial.
  10. A male koala is called a boomer. A female koala is called a doe. A baby koala is called a joey.
  11. The koala's brain has shrunk over evolutionary time.
  12. The koala prefers to live by itself.
  13. The koala eats eucalyptus leaves.
  14. But it only eats the leaves of 35 out of over 600 types of eucalyptus trees.
  15. This is because most types of eucalyptus are highly toxic.
  16. The koala uses its highly sensitive nose to sniff out the least poisonous leaves.
  17. The koala's poo) looks like a dark green olives and smells like eucalyptus.
  18. The koala gets the moisture it needs from its food and rarely drinks water.
  19. Koalas weigh 5-12 kilos. The female koala is about 50% smaller than the male.
  20. The female gives birth to a single baby koala, called a 'joey'.
  21. The joey is only the size of a human thumbnail when it is born.
  22. It looks like a pinkish jelly bean with tiny stumpy limbs, which it uses to crawl into its mother's pouch.
  23. Koalas were almost hunted to extinction.
  24. Their soft waterproof fur was used to make hats, gloves and linings for coats.
  25. Kolas live for 10-15 years.