The main reason why people shouldn’t try to take koalas out from their natural home is their diet. It’s a strict diet of eucalyptus leaves as koalas practically never eat anything else. In Australia there are over 600 types of eucalyptus, but koalas eat only 40–50 varieties with only about 10 being preferred. And even if you find the koala’s most favourite tree and plant it in your backyard, you won’t be able to supply your koala-pet with food anyway. The thing is that koalas eat only fresh young leaves, and the tree has few of them. So, to keep a koala happy and healthy, you would have to plant about 100 eucalyptus trees!

It’s difficult to explain why koalas love eucalyptus leaves so much. The leaves are tough and feel like rubber. They have very few calories and they are poisonous to most animals. Koalas, however, cope with such a diet easily. Nature has equipped them with specialised adaptations. Each koala eats approximately 200 to 500 grams of leaves per day. They are very slow eaters and they manage to get the maximum amount of energy from such a small amount of food. They also sleep for up to 18 hours per day in order to conserve energy.

Koalas spend all their lives on eucalyptus trees and they don’t have any need to leave them. Normally the animals don’t drink water as they receive it from the leaves. For this reason the koala got its name from an ancient Aboriginal word meaning “no drink”.

Koalas live in societies, just like humans, so they need to be able to come into contact with other koalas. They live in suitable eucalyptus forests which are large enough to support a healthy koala population and to allow for expansion by maturing young koalas. In spite of their peaceful and sleepy look, koalas are highly territorial animals and don’t allow strangers to approach their “home trees” and “food trees”.

A female koala gives birth to only one baby in one or two years. It's hairless, blind and very little – about 2 cms long! It gets into the mother's pouch – a special pocket of skin on the stomach – and stays there for six or seven months. Then it gets out of the pouch but stays with the mother until it's about one year old. Koalas are slow-breeding animals and their population can't grow fast. The animals were in danger of extinction at the beginning of the 20th century when the koala was hunted for its fur. Fortunately, the population has been restored and today the Australian government doesn't consider the koala as endangered.