KoalaPhascolarctos cinereusWhere and when to see them

The koala is an Australian tree-dwelling marsupial specialized for eating eucalyptus foliage. Its rounded ears, broad dark nose and tailless appearance make it unmistakable, but it is not a bear. Populations vary markedly in body size, density and conservation condition across eastern and southeastern Australia. Habitat clearing, vehicle collisions, dog attacks, disease and extreme heat are major pressures, and abundant animals in one locality do not indicate security everywhere.

Size

60-85 cm long

Weight

4-14 kg

Lifespan

10-15 years

Status

Vulnerable

Koalas spend much of the day resting in tree forks, conserving energy on a fibrous, relatively low-energy diet. Feeding and movement increase at night, although individuals may change trees or feed during daylight. Adults communicate through scent marking and unexpectedly deep vocalizations, especially during breeding. They descend to the ground to move between trees, exposing themselves to traffic and dogs. Young develop in a pouch before riding on their mother's body. Koalas typically rest for up to 18-20 hours a day to conserve energy, waking primarily at dusk to feed. Breeding season, usually from September to March, is when males are most vocal, emitting deep grunting calls to attract females and ward off rivals.

• Koalas are marsupials rather than bears.
• Their fingerprints have ridge patterns remarkably similar to human fingerprints.
• Young acquire important gut microbes by eating a specialized maternal substance called pap.
• Males possess additional vocal folds that help produce unusually low-pitched calls.

Koalas can be observed year-round in occupied habitat. April to October often provides comfortable walking conditions across many eastern and southeastern locations, though southern winters can be wet or cold. Local access, heat and fire risk matter more than a single nationwide wildlife season. Prime viewing often coincides with cooler periods when koalas are more active and less prone to heat stress, though they are always present. Dry, warm periods can increase fire risk in eucalypt forests, which should be considered for any onshore excursions.

Koalas occupy eucalypt forests and woodlands where suitable food trees, resting trees and connected vegetation remain. Some populations occur in coastal landscapes and suburban remnants. They are not distributed throughout Australia, and apparently suitable woodland may lack the particular tree species or local conditions they require. Habitat destruction, fragmentation, and climate change are significant threats to their populations, leading to increased stress and disease susceptibility. Their distribution is primarily concentrated in eastern and southeastern Australia, with significant populations in Queensland, New South Wales, Victoria, and a small population in South Australia.

Eucalyptus leaves dominate the diet, with strong preferences for particular species and individual trees. Some other related trees are also used. A specialized hindgut microbial community helps process fibrous foliage, while selective feeding limits exposure to plant chemicals and balances water and nutrient intake. They obtain most of their water needs from eucalyptus leaves, requiring minimal direct drinking water. Young koalas consume a special pap from their mother, which introduces essential gut bacteria for digesting eucalyptus.

Common name

Koala

Scientific name

Phascolarctos cinereus

Animal group

Mammals

Size

60-85 cm long

Weight

4-14 kg

Lifespan

10-15 years

Status

Vulnerable

Identification

Unlike wombats and possums, the koala combines an arboreal lifestyle with large fluffy ears, a prominent bare dark nose and no externally visible tail. Their large, dark, leathery nose is unique, distinguishing them from other arboreal marsupials. The fur coloration ranges from ash-grey to brownish, with lighter fur on their belly and large, prominent tufts of white fur inside their ears.