KoalaInteresting facts and information

• Not a bear: despite the name "koala bear", the koala is a marsupial; the female carries her tiny young in a pouch.
• Champion sleepers: koalas sleep or rest for about 18-22 hours a day, saving energy on their low-energy diet of leaves.
• They do drink: koalas get much of their water from leaves, but they also drink, especially in hot, dry weather, and lick rainwater from tree trunks.
• Two thumbs: on each front paw, two fingers face the other three, giving koalas a very strong grip on branches.
• A surprisingly deep voice: male koalas make loud, deep bellows thanks to special vocal folds outside the voice box.
• Fingerprints like ours: koalas have fingerprints that look remarkably similar to human fingerprints.
• Disease is a big problem: the bacterial disease chlamydia can cause blindness and infertility in koalas and affects many wild populations.

• The last of its family: the koala is the only living member of the family Phascolarctidae.
• A specialised diet: few mammals can live on eucalyptus leaves, which are tough, low in nutrients and contain toxic compounds.
• Slow living: koalas have a low metabolic rate, which helps them survive on poor food.
• Dense, woolly fur: it protects them from heat, cold and rain.
• Bigger in the south: koalas from Victoria and South Australia are larger and have thicker fur than those from Queensland.

Koalas are mammals built for climbing and for eating leaves, with strong gripping paws, sharp claws and a special digestive system.

Key physical adaptations

• Gripping hands and claws: the front paws have two digits that face the other three, helping them hold trunks and branches.
• Dense fur: keeps them warm and helps shed rain.
• A large, sensitive nose: koalas sniff leaves carefully to choose which ones to eat.
• A pouch: protects the joey while it grows during its first months.
• A very long caecum: this part of the gut, up to about 2 metres long, contains microbes that help break down tough leaves.

Koalas live mostly alone in trees, but their home ranges overlap with those of their neighbours. They are most active at night and around dusk.

Daily activity

• Long rests: most of the day is spent sleeping or resting in the fork of a tree.
• Active at night: they feed and move between trees mainly in the evening and at night.
• Careful climbers: their strong paws and claws let them climb trunks and move along branches.

Social and territorial interactions

• Scent marking: males have a scent gland on their chest and rub it against tree trunks.
• Bellowing: males bellow loudly, especially in the breeding season, to show their size and attract females.
• Fights: koalas usually avoid one another, but males may fight during the breeding season.

Defence

• Camouflage: their grey-brown fur blends in with tree trunks and branches.
• Claws and teeth: a frightened koala can scratch and bite hard, so wild koalas should never be handled.
• Danger on the ground: koalas come down to move between trees, which is when they are most at risk from cars and dogs.

Koalas live only in eastern and south-eastern Australia, in eucalyptus forests and woodlands where their food trees grow.

Regional distribution

Habitat types

• Eucalyptus forest and woodland: the trees give them food, shelter and routes for moving around.
• Coastal and hilly areas: koalas live in many kinds of woodland, as long as their food trees grow there.
• Drier inland areas: koalas live there mainly along rivers and creeks, where trees have more moisture.

Climate and habitat change

• Land clearing: farming and urban development remove and break up the woodland koalas need.
• Drought, heat and bushfire: severe droughts and fires destroy food trees and kill many koalas.
• Poorer leaves: higher temperatures and more carbon dioxide in the air can make eucalyptus leaves less nutritious.

Koalas are specialised leaf eaters that feed mainly on eucalyptus leaves. Their digestive system can cope with tough leaves that contain substances poisonous to most other animals.

What do koalas eat?

Feeding methods

• Choosing leaves: koalas sniff leaves and pick the most nutritious ones with the fewest toxins.
• Chewing: their grinding cheek teeth crush the leaves into a fine paste.
• Slow digestion: food stays a long time in the gut, where microbes help break it down.
• Pap for joeys: before eating leaves, joeys eat a special soft dropping from their mother called pap, which gives them the gut microbes they need.

Like other marsupials, koalas give birth to tiny, undeveloped young that keep growing in their mother's pouch.

Breeding season

• Most koalas breed in the warmer months, from about September to March.
• Males bellow loudly during the breeding season, and females are thought to use these calls to judge the size of males.

Gestation and birth

Raising young

• After birth, the joey crawls into the pouch and attaches to a teat, where it stays for about six months.
• After leaving the pouch, it keeps drinking milk and rides on its mother's back while it learns to eat leaves.
• Young koalas become independent at about 1 year old.

Survival

• Young koalas face dangers from disease, lack of food, predators, cars and dogs.
• Wild koalas usually live about 10-15 years; females often live longer than males.

Origin of the name

• The word "koala" comes from Dharug, an Aboriginal language of the Sydney area. It is often said to mean "no drink", but this is uncertain, and koalas do drink.
• The scientific name Phascolarctos cinereus comes from Greek words meaning "pouch" and "bear", and the Latin word for "ash-grey".

Taxonomic classification

Evolution and fossils

• The koala is the only living member of the family Phascolarctidae, but fossils show that there were once many kinds of koala.
• Koala relatives have lived in Australia for more than 20 million years; some extinct species were larger than today's koala.

The koala is one of Australia's best-known animals and appears in the stories of many Aboriginal peoples.

An Australian symbol

• Koalas are among Australia's national symbols, alongside kangaroos and emus.
• They appear on stamps and souvenirs, and the Perth Mint issues an annual Australian Koala bullion coin.
• Koalas are often the face of campaigns to protect wildlife and forests.

Modern public perceptions

• Koalas are a major tourist attraction, but despite their cuddly look they are wild animals; in most Australian states, holding a koala is not allowed.

The koala is listed as Vulnerable by the IUCN. In Australia, the koalas of Queensland, New South Wales and the Australian Capital Territory have been listed as Endangered since 2022.

Conservation status

Major threats

1. Habitat clearing: development and farming remove and split up the trees koalas need for food and shelter.
2. Bushfire: the 2019-2020 fires killed, injured or displaced tens of thousands of koalas.
3. Disease: chlamydia and koala retrovirus affect many populations.
4. Vehicle collisions: koalas crossing roads between patches of woodland are often hit by cars.
5. Dog attacks: domestic dogs attack koalas, especially when they are on the ground.
6. Climate change: heatwaves and droughts kill koalas and their food trees.

Protection measures

• Habitat restoration: planting food trees and creating wildlife corridors helps koalas move and feed.
• Wildlife hospitals: specialist hospitals treat injured and sick koalas.
• Protecting land: protecting important koala habitat reduces clearing.
• Disease research: scientists have developed a vaccine against chlamydia for koalas.
• Public education: people can help by driving carefully in koala areas and keeping dogs under control.

Koalas appear in many films, cartoons and children's books.

Film and animation

• Blinky Bill: the famous Australian koala has appeared in animated films and TV series, including films in 1992 and 2015.
• Sing (2016): the main character, Buster Moon, is a koala who runs a theatre.
• The Wild (2006): the animated film features Nigel, a grumpy koala.
• Back to the Outback (2021): the animated film features Pretty Boy, a spoiled koala.

Books and literature

• Blinky Bill, by Dorothy Wall (1933): classic Australian stories about a mischievous koala.
• Koala Lou, by Mem Fox (1988): a picture book about a young koala and her mother's love.
• Educational books: koalas are a favourite subject of children's books about Australian animals.

Tourism and marketing

• Tourism: koalas appear on souvenirs and in advertising for Australia.
• Qantas advertisements: from 1967, the airline ran famous TV ads with a koala complaining "I hate Qantas" because the airline brought tourists to Australia.
• Conservation: koalas are a popular symbol for protecting wildlife and forests.