What do humans, gorillas, chimpanzees, and koalas all have in common? We all have the same type of fingerprints! Koala and human fingerprints are so similar they are almost impossible to tell apart even under a microscope.
Humans, gorillas, and chimpanzees all have the same primate ancestors, so it makes sense we would have the same fingerprints. Koalas are not related to us though. It is believed they developed fingerprints independently of us.
Koalas are the only animal that are not primates that have fingerprints!
Koalas are marsupials, which means they are born very small (about the size of a jellybean) and then live and drink milk inside their mother’s pouch where it is safe for 6 months until they are big enough to come out.
The koala’s closest living relative is the wombat as they are both marsupials with backward facing pouches. You may have seen pictures of a kangaroo’s pouch which opens upward. A koala’s pouch opens more downward and toward the hind legs. It has a sphincter that keeps the joey from falling out.
Koalas are considered arboreal mammals, which means tree dwelling.
Koalas spend the majority of their time sleeping in trees. They sleep 18-22 hours every day!
Koala. They are sometimes called koala bears, but this term is incorrect as they are not bears and are not even related to bears!
Koalas are native to Australia. They live in eucalypt forests and woodlands in the coastal areas of Queensland, New South Wales, Victoria, and South Australia.
Koalas live high up in the trees and have a home range of trees they live in.
The Australian Koala Foundation estimates there may be between 43,000 and 80,000 koalas left in the wild.
Between 10 and 20 years with wild koalas living closer to 10-13 years on average and females usually live longer than males. The oldest koala recorded lived to be 23 and lived in captivity at the Lone Pine Koala Sanctuary in Queensland, Australia.
Adult size and weight
An adult koala has a body length of 24-33 inches (60-85 cm) and a weight of 9-33 pounds (4-15 kg). The koalas in the south are much larger than the ones in the north, and males are larger than females.
Koalas have poor vision and rely more upon their other senses.
Their sense of smell is their strongest sense. They have an excellent sense of smell which they use to smell the different types of eucalyptus and identify the best kinds to eat. They can even smell eucalyptus forests from miles away!
Since they have poor vision, they have excellent hearing which helps them detect predators and to hear other koalas.
Koalas are mostly nocturnal. They don’t get very much energy from their diet and it takes a lot of energy to digest the food they eat, so they limit how active they are. Koalas sleep and rest 18-22 hours a day and spend the remaining hours being active, which is spent mostly eating and is mainly at night.
They spend most of their time in trees, but occasionally have to walk on the ground to get to different trees.
Even though they spend most of their time in trees, koalas are actually pretty good swimmers. They don’t do it very often, but may swim across water to get to different trees.
Koalas are herbivores. They diet mainly consists of eucalyptus leaves. Eucalyptus trees are sometimes also called gum trees. There are around 600 different eucalyptus trees, but koalas only prefer to eat the leaves of about 3 dozen of those. Koalas eat 0.5 to 1 kg (1-2 pounds) of leaves per day.
Eucalyptus is poisonous to most animals. Koalas have a special bacteria that helps break down the toxic substances. Eucalyptus leaves are high in fiber but low in nutrition. Koalas have a very long cecum where their food stays a while to break down the high fiber content and to extract the most amount of nutrition they can.
Koalas also have special cheek teeth that help grind the tough leaves.
They have thick fur which protects them from the elements and repels water when it rains. Koalas have the thickest fur of all marsupials. It looks like it would be soft to touch, but it is actually coarse. Their fur can be grey or brown. The koalas in the south usually have thicker and darker fur than the koalas in the north.
Koalas are primarily solitary animals. There will usually only be one koala per tree unless it is a mother and her young. They have home ranges that sometimes overlap with other koala’s home ranges, but they spend their lives mostly alone.
Male vs female koalas
A male Koala is called a ‘buck’ and a female is called a ‘doe’. A baby Koala is called a ‘joey.’ Males are larger than females.
Male koalas have a bare patch on their chest where they have a scent gland. They mark their scent on trees and branches to mark their territory. This patch doesn’t become noticeable visually until they are a couple of years old and doesn’t get full size until about 5 or 6 years old.
Females usually look fluffier than males and have smaller facial features and a smaller nose. Males have a longer and broader nose.
Female koalas are sexually mature at about 3 years of age and males at about 3-4 years of age.
The mating season for koalas is around August/September through February/March. Koalas move around more during this time. Males become much more vocal during mating season.
Here is a video where you can hear a male koala!
Gestation time for a koala is only 30-36 days and they usually only have one joey at a time. They very rarely have twins.
Koala birth and growth to maturity
Koala joeys are born after a very short gestation. They are born about the size of a jellybean and they cannot see or hear. After they are born, they climb from the mother’s birth canal into her pouch. There are 2 nipples in the mother’s pouch where the joey will drink milk and grow for another 6 months.
After about 6 months, the joey will start weaning from its mother’s milk and start eating leaves. When it becomes too large to continue to live in the mother’s pouch, it will then ride on the mother’s back. When a koala is about a year old, it is able to leave its mother and live on its own where it will go off and find its own territory and trees to call home.
Do koalas attack humans?
Koala attacks are very rare. They are more likely to defend themselves against dogs when feeling threatened or being attacked. There is a story about a woman who was walking her dogs and a koala had to defend itself from the dogs. The woman tried to protect her dogs from the koala and got bit by the koala in the process and required stitches.
If you happen to be in Australia and come across a koala, even though they look cute and cuddly, it would be best to keep your distance in case it feels threatened. They do have sharp teeth and claws!
Threats to Koalas
Koalas have very few natural predators. Occasionally a large owl, eagle, large python, or dingo may take one. They spend the majority of their time in trees where they are safe from most predators. Getting hit by cars and taken by dogs are a much bigger threats than other predators. They are vulnerable to these when they go down to the ground to move to a different tree.
Other threats to koalas include bacteria like Chlamydia and viruses such as koala retrovirus.
Bush fires are dangerous to them as they are very slow moving and cannot get away fast enough.
The biggest threat to koalas is habitat loss due to human activity where their habitats are getting much smaller and fragmented due to clearing for human development. This causes them to have to go to ground more often to try to find other areas and it makes them even more vulnerable to getting hit by cars and killed by dogs.