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Everything there is to know about koalas
Koalas are cute and furry creatures. They live in Australia and are marsupials. This means they carry their babies in pouches in front of their bellies. The biggest population of koalas lives in Queensland, a state in the north-east of Australia. They are quiet and peaceful creatures without any natural enemies. Except for humans. As Australia becomes more and more developed and urbanised, the koala habitat gets smaller. The eucalyptus trees they feed on disappear, and every year more koalas die in car accidents and are killed by dogs. We should all work together to help this endangered species survive. Here is some more information on koalas.
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The habitat of koalas
Koalas live in Australia. Koalas feed on the leaves of eucalyptus trees, so they live in areas where there are lots of these trees. The Australian state Queensland has the largest population of koalas, but you will also find then in New South Wales, South Australia and Victoria Koalas reside in numerous different habitats, like coastal islands for example, or tall eucalyptus forests inland woodlands. They dont' like living in rain forests or swamp-like areas. A stable and healthy koala population is only possible when there are enough of their preferred eucalyptus trees. They tend to live in larger groups, as they need contact with other koalas, so there have to be enough trees to support larger numbers of koalas.
They are nocturnal animals. They spend most of their lives sleeping, about 16 to 20 hours a day. They sleep while sitting in the eucalyptus trees. Even when they are awake they spend a lot of their time resting, and eating of course. During the night they sometimes move around to find new trees to snack on. They have long clawed toes to make climbing trees easy. They are very slow moving animals. They do not have natural predators to worry about. But with Australia's population growing, the habitat of the koala gets smaller and smaller. As urban development takes over their habitats, more and more koalas fall prey to dogs, or car accidents. Koalas have very low tolerance for stress, due to having very small adrenal glands. Stress can cause latent diseases to manifest. In order to preserve the koalas we need to preserve and protect their habitats.
What do koalas eat?
Koalas eat the leaves of Eucalyptus trees. These leaves are very fibrous and poisonous for most animals, but koalas have developed a digestive system that can handle the leaves. They grind the eucalyptus leaves into a paste with their teeth. In their digestive tract there is a specific mix of bacteria which attack and break down the poisonous substances in the leaves. The bacteria also work to extract and produce the nutritional parts of the leaves the koalas need, like vitamins for example. But still there isn't much nutritional value in the leaves and their bodies don't store a lot of fat, which is why koalas spend so much of their time asleep, they need to be conservative with their energy.
Koalas do not normally drink water. They get all the water they need from the eucalyptus leaves. The leaves consist of close to 50% water. But when there are draughts affecting the water content of the leaves, then sometimes koalas drink water directly.
There are around 500 different types of eucalyptus trees, yet koalas only feed on about 12 of these. They learn what the scent of these leaves is, so they will be able to tell them apart from the species of which the leaves contain prussic acid. This prussic acid is toxic even to the koalas and their adapted digestive system. The eucalyptus trees in different parts of Australia are slightly different types of trees. This means the diets of koalas living in different areas also differ slightly.
Reproduction and baby koalas (called joeys)
Female koalas give birth to a baby once a year. The koalas are members of a group of mammals called marsupials, this means they carry their young in a pouch in front of their belly. Other family members are kangaroos and wombats. The baby koala is called a joey. Koalas are solitary animals, and the males and females only get together to mate. The gestation lasts 35 days. Koalas are pregnant with only one joey at a time.
As the joey is born it is very very small (like a raisin), blind, deaf and bald. But instinctively it will find its way up into the mama's pouch. In the pouch it latches on to on of the mother's nipples to drink. It will stay in the pouch for five to seven months, until it gets to big to stay in it. After climbing out of the pouch the little joey will stay with its mother for some time and grow to be an adult, and learn how to survive on its own. Sources differ on the time they stay with their mother, but it is usually around 2 years in total.
When they are adult koalas weigh between 6 and 12 kg. In the wild they will live to the ages of 8 to 10, but in captivity they usually get older. Some koalas in captivity have been known to reach 20 years of age.