Appearance
Koalas have soft, thick, grey or brown fur on their backs. The fur on the stomach is white. Koalas that live in the south have thicker fur than those in the north because of the cold winters, whereas the koalas in the northern part of the country live in warm to hot weather most of the year so have thinner fur. A koala has a large, hairless noses and round ears. Koalas don't have tails. Adult koalas measure between 64 to 76 centimetres in length and weigh between 7 and 14 kilograms.
Koalas have strong, sharp claws and long toes to help them climb. The front paws have two thumbs to help them grip branches strongly. The second and third toes on the back legs are joined together to form a grooming claw.
Although mostly silent, koalas communicate with each other using a range of noises ranging from one that sounds like a loud snore, and a burping sound, to a loud bellow.
https://www.savethekoala.com/sounds/koalagrunt.wav">Go here to hear the sounds of a koala
Diet
Koalas eat the leaves and young shoots of some kinds of eucalyptus (say you-kul-ip-tus) trees. In Australia there are over 600 species, or kinds, of eucalypts, but koalas only eat about 20 species. Within a particular area, there will be only three or four species of those eucalypts that will be regularly browsed (eaten) by koalas. A variety of other species, including some non-eucalypts, are eaten by koalas occasionally or used for just sitting or sleeping in. Different species of eucalypts grow in different parts of Australia, so a koala in Victoria has a very different diet from one in Queensland.
Habits
Koalas spend nearly all their time in the trees using their sharp, curved claws and long toes to climb about and to hold on to the tree branches. They sleep most of the day, and feed and move from tree to tree mainly at night.
The reason koalas sleep for much of the day is because eucalyptus leaves are very tough so they use a lot of energy to digest. Sleeping saves energy. Eucalyptus leaves are poisonous to almost every other animal.
Koalas don't often drink water, as they get moisture from eucalyptus leaves. However, in a severe drought, there is less moisture in leaves so koalas will then need to find water to drink.
Each koala has a home range made up of several trees that they visit regularly. They normally do not visit another koala's home trees except when a male is looking for a female to mate with.
Life Cycle
Breeding season is generally from August to February. During this time the males will be heard bellowing as they compete for females. At this time the young from the previous year are ready to leave their mothers and become independent. Usually a female has one young each year, but may not breed in some years.
About 35 days after mating, a tiny baby called a joey is born. It is about 2 cm long, weighs less than 1 gram and is pink, hairless, blind and without ears. Amazingly, this tiny creature travels up its mother's belly and finds the entrance to the pouch. Inside the pouch, it attaches itself to a teat that immediately swells inside its mouth so that the joey cannot let go and lose the teat. The female is able to tighten muscles at the opening of the pouch to prevent the baby falling out.
The female carries her baby in the pouch for 6 or 7 months after it is born. The baby, called a joey, feeds on its mother's milk inside the pouch. Between 22 and 30 weeks of age, its mother starts feeding the joey a substance called pap formed from pre-digested food and her droppings. This is important, because it trains the joey to be able to eat eucalyptus, which is poisonous to most mammals. After it leaves the pouch, the baby travels around on its mother's back, but continues to drink milk until a year old. Generally this is when a young one leaves its mother, but if she does not breed then the young one stays longer.
