We’re celebrating Wild Koala Day on May 3 with some fascinating facts about koalas, those cuddly mammals of the Australian bush.
The Koala is one of Australia’s many endemic mammals. They are often referred to as Koala Bears, but this is inaccurate, as Koalas are more closely related to marsupials such as Wombats. Although they are symbolic of Australia as a whole, they’re actually only found in the eastern and southeastern parts of the country. Primarily they can be seen on wildlife tours in New South Wales, South Australia, Queensland and Victoria.
Koalas’ Physical Features
Koalas are instantly recognisable and universally appealing, with their stout bodies, round ears and large black noses. Unlike many other tree-dwelling mammals, they do not have a tail. There are signs at the end of their spines, though, that indicate they may have had one at some point in evolution.
Although they look fluffy, Koalas have hair that is more akin to a sheep’s wool. It has an amount of natural waterproofing and, being quite dense, it protects the animal from both the strong Australian sun and the cold in winter. To make sitting on tough branches more comfortable, Koalas have strong cartilage at the base of their spine and their fur is thick and compacted in that area. These attributes provide them with a built-in cushion to rest on when feeding or sleeping.
Koalas’ arms and legs are almost the same in length. This helps them to climb trees efficiently, as does the fact that the muscles of the tops of their legs attach much lower down the fronts of their lower legs than other mammals. This makes for stronger, more athletic legs. They have two opposable ‘fingers’ on each front foot that can be moved separately to the other three. And they have long nails and rough pads on both their front and back feet to give a good grip. Two toes on each back foot are fused together, which is an adaptation that helps them with grooming and removing ticks. Curiously, like humans, Koalas have individual fingerprints that are unique to each animal.
Photo Credit: David Clode, Two opposable ‘fingers’ on each front foot help a Koala’s grip.
Koala Diet and Eating Habits
A Koala’s diet consists solely of eucalyptus leaves, which are poisonous to many other animals. Their large, leathery noses give them a keen olfactory sense and they use this to smell out the less toxic leaves. To help detoxify the chemicals within the leaves, Koalas use a special organ called a caecum, which is especially designed to digest fibre. Other animals, including humans, also have a caecum but a Koala’s is 2m long! This is a necessary adaptation because, a small animal, they can eat up to a kilo of leaves in a single day. So processing that volume of fibre is a time- and energy-consuming activity.
Despite this restricted diet, Koalas are surprisingly choosy about their leaves. Out of more than 700 species of eucalyptus trees in Australia, Koalas browse from fewer than 50. Eucalyptus leaves are low in nutrients, so Koalas will only select those leaves containing the most goodness, generally found at the very tops of the trees. Low nutrient consumption, however, means Koalas need to conserve energy. They sleep more than most animals – between 18 and 22 hours a day – and tend to be nocturnal. This is why you have to look for them high up in native forests, settled and snoozing in the branching forks of eucalyptus trees during the day.
Koalas also have a habit of storing leaves in their cheeks for later. Their name means ‘no water’ and comes from the Australian Aboriginal language Dharug, in which the animal is called a gula or kula. The reason for the name is because they were originally thought to get most of the moisture they needed from the eucalyptus leaves. Nowadays, studies have shown that they also hydrate by licking the trunks of trees after rain. This saves them having to make the long climb down to the ground to find water.
Photo Credit: Shutterstock, Tough eucalyptus leaves are a Koala’s only food source.
Facts about Koalas’ Behaviour
While most people know what a Koala looks like, what is less known is what sounds they make. These vary widely. Baby Koalas call to their mothers in high-pitched squeaks. A stranger sound is the pig-like grunt vocalisation made by males when looking for females.
A Koala’s breeding season runs from August to March. Like kangaroos, young Koalas are called joeys and are born without fur or developed eyes and ears. Only 2cm long at birth, a newborn joey makes a challenging journey through its mother’s fur from the birth canal to her pouch. Once there, it spends the next six months developing.
When the joey emerges, it climbs onto its mother’s back and immediately begins feeding on leaves. It only returns to the pouch to sleep and gain additional nutrition from her milk. By the time a joey is one or two years of age, there is usually another youngster being born. This is the trigger for the older joey to leave its mother’s territory and establish its own home range elsewhere.
Threats to Wild Koalas
In the late 19th to early 20th century, Koala populations crashed as a result of the fur trade. Today they are listed as Vulnerable on the IUCN Red List of Threatened Species. Global warming and deforestation are some of the biggest modern threats facing Koalas. It’s believed that climate change is making the nutritional quality of eucalyptus leaves even lower. These climatic conditions are also causing more intense droughts and wildfires that destroy Koalas’ habitat.
Extreme tree-clearing is taking place in parts of New South Wales and Queensland to make way for urban developments and agriculture. Koala territories vary in size depending on the quality of bushland habitat but often encompass 100 trees per individual. Each of these trees is significant to a Koala. When one of its trees is felled it cannot simply move, as its range will overlap with those of neighbouring Koalas.
Without trees, Koalas are forced to forage on the ground. This increases the risk of natural predation by Dingoes and large owls. The species also suffers from greater numbers of collisions with cars and from domestic dog attacks. Stressful situations can induce diseases such as chlamydia to take hold. This is a different strain to the chlamydia that affects humans. In Koalas the infection causes blindness and infertility.
Photo Credit: Alex Eckerman, A Koala will spend a large part of its life asleep in the fork of a tree.
Facts about Koalas after the Wildfires
The devastating Australian wildfires in 2019 and 2020 dominated news headlines. They were some of the most catastrophic bushfires ever recorded. The fires resulted in the deaths or serious harm of an estimated three billion animals, including at least 30,000 Koalas. Kangaroo Island, southwest of Adelaide, was hit particularly hard and over a third of the island’s vegetation was burned.
The Koalas on Kangaroo Island are historically chlamydia-free. However, this means they have no immunity to the disease so they could not be relocated to the mainland when the fires came. Rescue teams managed to save many burned and disorientated Koalas and took them to rehabilitation centres such as the Kangaroo Island Wildlife Park. Donations and medical supplies arrived at the Park from around the world. Eventually, conservationists hope that all the treated Koalas will be released back into the wild.
In February 2021, a new refuge was opened on Kangaroo Island to protect endangered species affected by the bushfires. The 370-hectare area is surrounded by a six-foot anti-predator fence. Feral cats are the biggest threat to wild mammals in Australia, so it’s hoped the fence will ensure these invasive predators cannot access the refuge.
Photo Credit: Araucaria Ecotours, The Koala is a symbol of Australian wildlife that needs help to survive.
Even without the wildfires, the fact is Koalas are struggling. The Australian Koala Foundation (AKF) has accused the Federal Government of wasting time with a Koala count project. It believes the priority should be saving forest habitat, as current legislation does not prevent trees from being cleared. The AKF is pushing for the Koala Protection Act – legislation that will focus on protecting trees. This would not just be for Koalas but for all species that depend on native trees for food and shelter.
As it is such an endearing animal, the Koala has become an ambassador for Australia’s wildlife as a whole. Protecting bushland habitat to help Koalas is also helping other species including Wombats, possums and a wide range of other endemic birds and reptiles.
Want to See Koalas in the Wild?
The local Australian wildlife tour operators on Blue Sky Wildlife can take you on a fabulous trip to see a wide range of Australian native animals, including Koalas. Arrange your trip using the enquiry form on their pages.
Rebecca Gibson is a wildlife writer based in the UK. She is currently studying for an MA in Travel and Nature Writing at Bath Spa University and uses her blog to share her writing and photography and raise awareness of British wildlife.
Original Date of Publish: 2nd May 2021