| Common name | Koala |
| Scientific name | Phascolarctos cinereus |
| Type | Mammalia (mammals) |
| Diet | Eucalyptus leaves |
| Average lifespan | Between 10-18 years |
| Size | Southern koalas (Victoria and South Australia): females weigh 7kg–11kg, males 9.5–14.5kg; northern koalas (Queensland and New South Wales): females weigh 4kg–7kg, males 4kg–9kg |
Conservation status (Australia): Endangered in Queensland, New South Wales and the Australian Capital Territory
There’s nothing more Aussie than a koala up a gumtree, and this much-loved marsupial is found nowhere else in the world. With their habitat sadly under threat, and numbers declining, the koala is the last surviving member of the Phascolarctidae family and needs our protection.
Often wrongly referred to as a bear, koalas have a stocky body, no tail, and are covered in thick ash-grey fur with white underbelly. A large round head, fluffy ears, and a black leathery rectangle-shaped nose make this animal unmistakably unique.
Feeding primarily on leaves from certain varieties of eucalyptus trees, this low-nutrient diet gives the koala little energy to spare. They can spend up to 20 hours a day sleeping.
This fluffy tree-dwelling marsupial has a slow metabolic rate that allows it to conserve energy. Koalas have a long caecum – a pouch-like structure near the large intestine – that allows them to digest eucalyptus leaves that are high in fibre.
Habitat
Koalas occur in eucalypt forests and woodlands.
Distribution
Koalas are found along the east coast of Australia from northern Queensland to southern Victoria as well as south-eastern South Australia. Depending on their location, koalas vary in size and colour. Southern populations in Victoria and South Australia are usually much larger than their northern cousins in Queensland and New South Wales and have thicker fur, which is likely an adaptation to the cooler climate.
Reproduction
Koalas breed during summer. Females will typically give birth to one joey 35 days after mating. The newborn joey is blind, hairless and about 2cm long – the size of a jellybean. Immediately after birth, the joey climbs from its mother’s birth canal to her pouch and attaches itself to her teat. The joey won’t poke its head out of her pouch for another 22 weeks.
The juvenile koala is slowly weaned from milk by feeding on an unusual soft liquid faeces called pap from its mother. This substance introduces live bacteria to the joey’s gut that’s necessary for digesting gum leaves. After a full six months in the pouch, the joey then hitches a ride on mum’s back or abdomen but still returns to the pouch to drink milk until it grows too big to fit! The koala will be fully weaned when it’s about 12 months old and will forage in a home range that overlaps with its mother’s. By the time it’s two or three years old, the koala travels further away to find its own home range of suitable trees.
Conservation Status
In 2022 koala populations in Queensland, New South Wales and the Australian Capital Territory were listed as an endangered species under the EPBC Act. Koalas are not listed as a threatened species in Victoria or South Australia.
Threats
Major threats include land clearing and habitat loss. Koalas are also affected by diseases such as Chlamydia, which can impact their immune system, cause infertility and decrease their life expectancy.
Fascinating fact
Territorial and solitary animals, koalas use several sounds, including growling, belching, and bellowing to communicate with each other. Adult males have scent glands on their chest that they rub on trees to mark their territory and attract females.
Adult koalas can munch on up to 500g to 1kg of leaves each night.
