KOALA

Phascolarctos cinereus

MAMMAL

Order Marsupial

Habitat

Eucalyptus (gum tree) forests and woodlands.

Niche

Strictly arboreal, living in and feeding on the leaves of eucalyptus trees. Caecum of gut is greatly enlarged (about 6 ft. long) and houses a large bacterial colony that aids in leaf digestion. Usually comes to ground only to change trees. Preyed upon at those times by foxes and dingos. Young hunted by large birds of prey.

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.

Life History

Mating occurs Nov-Feb in the south, Sep-Jan further north. Gestation about 35 days; single young weigh about 1/5 oz and are about 3/4 in long. Newborn crawls from cloaca to pouch and attaches to a nipple to complete its development. Leaves pouch .first at about 5.5 months, permanently at about 8 months. Young joey then clings to mother’s back or stomach, sticking head into pouch to feed. During weaning, joey eats partially-digested eucalyptus that emerges from mother’s cloaca, thus receiving bacteria needed for digestion as well as food. Life span 12+ yrs (wild) 16+ yrs (captivity).

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.

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.

General characteristics

They aren’t even related to bears. The reason the koala is called a koala bear is because the koala looks like a teddy bear. The koala is related to the kangaroo. The koala’s nickname is a Native Bear. The koala is a mammal. They are warm-blooded. The koala’s young is called a cub. The koala’s young are born alive. Koalas drink milk from the mother. The koala breaths oxygen from air. The koala might look all cuddly but the koala has very sharp teeth and very sharp claws.

Koalas live for 20 or more years. The koala can run as fast as a rabbit. The koalas sleep for up to 19 hours. The koala’s territory is getting smaller because people are cutting down trees and making farms on them. Koalas can only live in one place in the world. The koala only eats Eucalyptus leaves and it eats so many leaves, it smells like the leaves. The koala hops from tree to tree and climbs the trees to get the leaves. The koala will eat 2.5 pounds of food a day. It uses its claws to get the branches and get the leaves. The koala used to be endangered because people would kill the koala for its fur. But now its against the law to kill the koala. Over 2 million koalas were killed between1908 and 1927. Occasionally koalas are taken by Goannas, Eagles, and Owls. Humans are koala’s worst enemies. Dingoes will kill the koala. Now there are 2,000 to 8.000 koalas in the wild. The koala does not have very many enemies.

Danger of extinction

Loss of koala habitat is the major threat facing koalas today. Since white settlement of Australia, roughly 80% of the koala’s habitat has been destroyed and of what remains, most occurs on privately owned land and almost none is protected.

Koalas face additional threats such as road death, dog attack, disease and bushfire. From a national population of around 100,000 koalas, roughly 4000 are killed by dogs and cars each year. In the 1920s approximately 3 million koalas were shot for their fur. Today the koala is a protected species but its habitat is not protected.

The koala is arguably now on the brink of disaster in many parts of its remaining geographic range. Regardless of recent public debates over population estimates, there is little disagreement over the dramatic extent of habitat clearing, degradation and fragmentation, nor about the fact that numbers have declined to a fraction of the millions that existed at the time of legalised hunting for the fur trade, which continued until as recently as the 1920’s.

The only way to save koalas is to save their habitat, the eucalyptus forests where they live, and which they must have to survive. This is what the Australian Koala Foundation is trying to achieve.

Now a disease called chlamydia (say clu-mid-ee-u), which makes koalas blind and makes the females unable to have babies, is harming these animals. Many koalas die because of the disease. Conservation organisations in Australia and around the world are working hard to help save the koalas.

Sources: Members, Kid cyber

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