Koalas 101

Koalas are not bears—they’re marsupials. Learn about koalas’ unique traits, including six opposable "thumbs,"downward-facing pouches, and a tendency to sleep nearly all day in tree branches.
Common Name:
Koala
Scientific Name:
Phascolarctos cinereus
Type:
Mammals
Diet:
Herbivore
Average Life Span In The Wild:
20 years
Size:
23.5 to 33.5 inches
Weight:
20 pounds
IUCN Red List Status:
Vulnerable
Current Population Trend:
Decreasing

What is the koala?

The koala is an iconic Australian animal. Often called the koala “bear,” this tree-climbing animal is a marsupial—a mammal with a pouch for the development of offspring.

Though koalas look fuzzy, their hair is more like the coarse wool of a sheep. They have two opposing thumbs on their hands, and both their feet and hands have rough pads and claws to grab onto branches. They have two toes, fused together, on their feet, which they use to comb their fur.

Habitat, behavior, and diet

Koalas live in the eucalyptus forests of southeastern and eastern Australia. When not sleeping, they’re usually eating. They rely on the eucalyptus tree for both habitat and food. Koalas can eat more than a pound of eucalyptus leaves a day. Eucalyptus is toxic, so the koala’s digestive system has to work hard to digest it, breaking down the toxins and extracting limited nutrients.

That’s why koalas sleep so much—they get very little energy from their diet. Tucked into forks or nooks in the trees, koalas may sleep for 18 to 22 hours.

Koalas usually don’t drink much water as they get most of their moisture from these leaves. Koalas can even store leaves in their cheek pouches for later. They eat so much eucalyptus that they often take on its smell.

Threats to survival

Koala numbers plummeted in the late 19th and early 20th century from hunting for their fur. Now they face serious threats from habitat loss. Land clearing, logging, and bushfires—especially the devastating 2019-2020 season—have destroyed much of the forest they live in. Koalas need a lot of space—about a hundred trees per animal—a pressing problem as Australia's woodlands continue to shrink.

Koalas are listed as vulnerable by the International Union for the Conservation of Nature, which has named the species one of 10 animals most vulnerable to climate change. Increasing carbon dioxide in the atmosphere is decreasing the nutritional quality of eucalyptus leaves (which is already quite low) and causing longer, more intense droughts and wildfires. In response to drought, koalas are forced to stop napping and come down from the trees to find water, spending precious energy and putting them at a higher risk of predation.

Predators include dingoes and large owls. They’re also at risk of getting hit by cars and attacked by dogs. Chlamydia is widespread in some koala populations and can cause blindness, infertility, and sometimes death.

Conservation

Koalas lost substantial portions of their habitat in the 2019-2020 bushfire season and have been identified by the Australian government as one of 113 animals requiring urgent help. Wildlife hospitals, rescue organizations, zoos, and volunteers have stepped up to care for injured koalas, with the goal of rehabilitating and releasing them back into the wild.

Ensuring there’s the right kind of forest for them to return to is a priority. Though there are some koala sanctuaries and reserves, many live on private, unprotected land. There are conservation efforts by the Australia Zoo and others to buy large tracts of land to set aside for koalas, and state governments are also creating new koala reserves. Campaigns urging landowners not to cut down eucalyptus trees are also ongoing.

Research is another important component of conservation efforts. Understanding koala genetics, mating choices, and health will shed light on koala biology that’s important for developing plans to better protect the species.

<p>A koala with her offspring photographed at Australia Zoo in Beerwah.</p>

A koala with her offspring photographed at Australia Zoo in Beerwah.

Photograph by Joel Sartore, National Geographic Photo Ark
This photo was submitted to Your Shot, our photo community on Instagram. Follow us on Instagram at @natgeoyourshot or visit us at natgeo.com/yourshot for the latest submissions and news about the community.
This photo was submitted to Your Shot, our photo community on Instagram. Follow us on Instagram at @natgeoyourshot or visit us at natgeo.com/yourshot for the latest submissions and news about the community.
Photograph by T. Dingle, National Geographic Your Shot

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