Koalas Essay, Research Paper
It used to take thousands of years before a species became extinct due to natural changes in the environment. Now, more than ever before many species of animals are on their way to becoming extinct. This is called an endangered species. An endangered species is a species that is exposed to danger, harm or loss threatening to diminish their overall population. It is important that we pay close attention to the cause of endangering a species. Once a species becomes extinct, they are truly a thing of the past. A good example of this is dinosaurs. No one really knows what caused them to totally be wiped off this planet. But we do know that dinosaurs are probably one of the most interesting forms of life ever to roam the world.
The koala is Australian?s favorite animal. It is a native species of Australia, it is also one of the most endangered. During the last century, the koala has suffered from the destruction of its natural living space. The interest of hunters, and the outbreak of several diseases. And all this despite its wonderful appearance and the affection shown to the many admirers out there.
The koala is often know as the Australian ?teddy bear,? but it is not a bear at all. It is a marsupial, a mammal that carries it?s young in a pouch. It is also an ancient animal. Fossils of koalas similar to those today have been found in rocks over 15 million years old. ?Koala? is an Aboriginal word. At a campsite, a container of water is passed from one person to another and if anyone is not thirsty they say ?Koala,? meaning ?no drink.? The koala got its name because it does not appear to drink; it gets the moisture it needs from the leave it eats.
There were once millions of koalas in eastern Australia, but now there are thought to be only about 400,000 left. Although the overall population is not threatened with extinction, local isolated populations, such as those in parts of Southern Australia, have disappeared. The distribution of koalas today is very scattered. Koalas were once found throughout Australia, but changes in climate and vegetation have led to a decline in numbers. In Central Australia forests gave way to desert and so the koalas were confined to the west and east coasts between desert and sea. Then, the settlers arrived. First the Aborigines came, and they wiped out all the koalas in the Southwest of Australia. Two hundreds years ago, the Europeans arrived on the eastern coast and they began to poach. The Europeans killed many animals including the koala and its land the forests that it lives in. With them came several epidemics that caused the koalas to die.
Koalas live in a long, narrow strip of eastern Australia, near the coast of the Pacific Ocean. This area includes several different climates, and there are some differences among the koalas that make their homes there. For example, in the cool southern state of Victoria, koalas are larger and have darker, thicker fur than their relatives in the warmer north.
An average adult male koala in Victoria measures about 2 ? feet in length and weighs as much as 30 pounds. In the north, a Queensland male koala may be only 2 feet tall and weigh around 15 pounds. In all areas, females are smaller than males.
Koalas make their homes in the forests of eucalyptus, or eucalypt, tees that grow in eastern Australia. They spend almost their entire lives up among the branches of the trees. They survive on the natural flora of this particular area. The eucalyptus provides food, shelter, and almost everything else the marsupials need to survive. They are very ?fussy? about the kinds of eucalyptus leaves they will eat. There are over 600 different types of eucalyptus trees growing in all parts of Australia, but koalas only eat the leaves of 35 kinds that grow in Australia. Some koalas eat only one or two types of leaves. If they can?t find the leaves, they will simply not eat. Since the trees are getting cut down for farmland more food is being taken away from the koala.
Koalas are not very social animals. They do not live together in groups or families. A young koala stays with its mother for about a year and then goes off on its own. But even while living alone in the eucalyptus forests, koalas have ways of keeping in touch. Scientists who study koalas have found that each adult in a particular region has a home range. This special area contains enough eucalyptus trees to supply the koala with food and shelter. The animal usually stays in its home range for most of its life, moving from tree to tree in search of fresh leaves.
A koala marks the trees around the boundary of its home range to let other koalas know where this special place is. It scratches the tree trunks with its sharp claws. A male koala has another way of marking trees n the borders of his territory. He rubs them with a smelly liquid produced by a scent gland in the middle of his chest. Usually one male will have a larger home range than neighboring koalas. He is the dominant ale in the area, his borders overlap the home ranges of several females. When mating season comes along he will most likely mate with these females.
During the breading season, which peaks on November on the north, December in the south, male koalas can become very aggressive and noisy. They bellow constantly and fight with other males for the right to mate. Each dominant male has over a clutch of up to eight females that live within his home range. If other males approach this home range, they are attacked violently and can be badly bitten. When the females have weaned last year?s youngster, they come into heat for just a few days during mating season. The male koala will try to mate at any time. Unreceptive females snarl their protests, but are ignored and seized by the back of the neck while the male attempts to mate. The male koala is capable of mating successfully at about two years of age, but it is unlikely that he will command the attention of his own group of females until he is fully-grown at about five years old. Only then will he advertise his availability with the loud two-note call that can travel more than a mile through the eucalyptus forest. Receptive females also call when they are ready to mate, but a little more quietly. It is thought that calls are a means by which males and females can find each other quickly. Mating itself is a very brief affair, only talking a couple minutes. It usually takes place in the trees.
Koala population numbers have been an area of controversy with many differing opinions concerning estimated numbers and the survival status of the koala. Population sizes differ between localities and the process of data collection has proved to be expensive and time consuming. When analyzing the survival status of the koala consideration must also be given as to the possibility of existing population groups in terms of reproductive capacity and disease status. Currently the Australian Koala Foundation (a research body) has been compiling data through comprehensive research within known habitat areas.
The survival status of the koala varies between Australian States and locations within states, with listings varying from endangered to vulnerable. The koala is distributed along the East Coast of Australia, ranging from North Queensland, New South Wales, Victoria and a small area within South Australia. There is no disputing the fact that koala population numbers are declining at a phenomenal rate. Habitat destruction is the single most important factor causing depletion of wild koala populations. The koala has disappeared from greater than 50% of its original range.
During the 1920’s the koala was hunted for its fur. Numbers have been greatly reduced since then, from millions to a matter of mere thousands. The koala is now threatened, not by guns but by something more sinister and less obvious . . . DEVELOPMENT.
The habitat in which the koala lives and depends upon for its survival is being destroyed at a phenomenal rate. It has had to adapt or adjust to new circumstances making survival harder. Destruction and fragmentation of the habitat has resulted in crowding of the surviving koalas. Deforestation has played a big factor in destroying their natural habitat. As new town erupt, forest areas are cleared reducing the number of places in which koalas can live. Over crowding in small forest patches also has led to the population becoming extinct. Increased exposure to the dangers of road traffic and domestic dogs. There has also been a subsequent increase in the spread and prevalence of disease in affected populations. The outbreak of several diseases has over time thinned the population. A virus-like bacterium called Chlamydia psittaci is infecting 40% of all koalas and causing diseases that can kill in large numbers. Threatening this species.
The Australian Koala Foundation was set up in 1986 to right some of these wrongs. The Australian Koala Foundation has collected 2 million dollars that is going to be used to fund the new koala research projects. Public awareness has increases, Local authorities, Mining companies, Agricultural concerns, and Children in Australia are helping to establish Eucalyptus forests specially for Koalas. There have been fines placed so that if you harm a koala you will be forced to pay up to a 2000 dollar fine. But, despite the change of attitude, many of the problems remain. Eucalyptus forests are still being destroyed due to the ever so increasing population of Australia. Despite Medical breakthroughs the many diseases that can harm koalas are still a threat. One major epidemic, could wipe out most of the koalas that live in the forests of Australia.
Since we are know in the new millenium we should be looking in the direction of the future. In order for the humans to live in peace with the animals that have inhabited earth for many years before we came, I believe we will have to stop taking away from their rightful land. We have been cutting away at the rainforests, one of the most important places for us. It provides us with oxygen and biodiversity. Many people do not know that we get most of our medicines from the Rain forests. If we wipe out the forests it is just hurting our self?s. We need to realize that in the end we are just taking away some of the most extravagant habitats on earth.
koalas by micheal bright
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