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Endangered Species 3 Essay Research Paper Endangered

Endangered Species 3 Essay, Research Paper

Endangered Species

All over the world there are species of animals and plants that are said to be “endangered”. By calling them endangered, scientists say that they think the species will become extinct if something isn’t done about them. Many more species are now threatened with extinction than ther should be because of many reasons. A species becomes endangered when there are fewer and fewer individuals of the species each year. There are many endagered species like the majestic Siberian tiger or the fascinating Polar Bear, which one day might be extinct and we may never see it again. Only through pictures will people see it. Once these species are gone, then they’re gone forever. Many reasons are killing more and more species every year either from human activity or natural disaaters. One way or the other, species like the Silver-Back Gorilla or the Black-footed Ferret almost face extinction. Here is a list of endangered animals:Bottle Dolphin, Peacock, Wolf, Emperor Penguin, Koala, Reticulated Giraffe, Snowy Owl, and unfortunately hunderds of more. The death of these animals each year are all different and sometimes so simple.

There are two different kinds of causes that drastically cut Down the number of these endangered species:

Direct Causes

Direct Causes is when the animals are purposely hunted, trapped, fished, whaled, or seled to extinction. Hunting for sport has been responsible for endangering such animals as the Polar Bear and the Siberian Tiger. But the endangerment of most species that are hunted or trapped today results mainly of commercial activities. Among the animals that have become endangered for commercial reasons are several species of whales, including the enormous Blue Whale; many of the spotted cats, such as the Cheetah; and some kinds of Alligators, Crocodiles, lizards, and snakes. the Whales have been kiled for their oil,

the cats for their furs, and the reptiles for their skins. For the most part, these animals arenow protectedby law, either undr international agreement or by local laws.

Animals may also be killed when they interfere wiyh human activity. Wolves became endangered because they preyed on livestock. they were hunted and trapped by livestock holders in such large numbers,that they disapeared from most parts of the world where they once lived.

Sometimes killing one species affects the population of another. Ranchers in the United states poisined prairie dogs because these rodents ate the grass and made burrows under land that was wanted for cattle. By killing prairie dogs, the ranchers caused the total extinction of the black-footed ferret.

Indirect Causes

The major indirect cause of endangement to animals throughput the world is the loss of a place to live. As the humane population increases : more land is needed for homesited, for the growing of crops, and fpr yeilding the minerals and fuels that people need. Many animals that live in the great forest, such as the monkeys of the Amazon Basin in South America and the lemurson theh island of Madagascon in the indian ocean are disappearing fast.

They are not disappearing because they are being killed but because the trees that provide their and shelter are being cut down for lumber and for space to grow crops. In central Africa the mountain gorilla is presently endangered because its forest home is being cut down. The same is true for the Asian ape and orangutan.

Another indirect cause of endagerment has come from chemical poisining of the enviorment. When the chemical DDT was widley used in the U.S to control pests, it washed off the plants to the soil and then into streama, rivers, and oceans. There it was taken up with food by tiny sea animals.When fish ate these animals, they, too, accumalated the poisin in their systems. And when birds such as osprey, bald eagles, and pelicans ate the fish, the chemicals affected the eggs laid by these birds. They began to produce eggs with shells so thin that they broke when the parents sat on them to keep them warm. Some birds stopped laying eggs completely.

Other poisins such as mercury, which is used in agriculture and industry, and polychlorinated biphenyls, knowmas PcB’s, have found their way into oceans. There they are taken in by fish that are the eaten by sealions, seals, polar bears, and penguins- often far from the place where the chemicals origanally came from.

These animals may then be poisined by eating the fish. Eating the poisined fish would be the indirect cause of endangerment to the large sea animals.

Polluting of the waters is also of great concen because of other forms of sealife that have been poisined may be eaten by people. Accidental poisining of water supplies used by people- poisining, for example, by industrial pollutants- is another threat to human life. Many animals are threatened too.

Tigers are vanishing from the Earth. Of eight subspecie three, theBali, Caspian, and the Javan tigers, have bcome extinct in the past 50 to 70 years. The remaining five subspecies-the Bengal or Indian, Indochinese, Siberian, Southchina, and Sumatran tigers- are endangered and in serious jeopardy of following in the paw-prints of their brothers. As recently as 1900, aproximately 100,000 tigers romed the continent of Asia. Now tigers are disapearing at an alarming rate, and less than 8,000 tigers are believed to remain in the wild. The biggest threats to these stunning cats are loss of habitat and poaching. Many areas inhabitedby tigers have been taken over by humans for agriculture, fragmenting the tiger populations, and preventing breeding.Tigers are alo hunted illegally for parts, whichare used in traditional Chinese medicines, and can fetch high prices on the Black Market.

Unless thes practices are stopped, future generations may only learn about tigers as another extinct animal, like dinosaurs and dodo.

The Peregrine falcon is a very endangered bird but is the fastest bird in the world. It can dive through the air at up to 200 miles (about 320km) per hour. Some people call it the “Thunderbolt bird” because it seems as fast as lightning.

Pergrine falcons are birds of prey (birds that hunt other animals) and specialize in hunting birds their speeds helps to mke then fierce hunters. They dive through the sky and snatch their prey out of the air. Peregrine falcons can be found throughtout the world, but unfortanetly most of them are killed.

Peregines were sacred to the Egyptions, for example, an important Egyption god had the shape of a falcon. For thousands of years people in many cultures trained peregines to act as hunters in a sport called falconry. The peregine falcon was the people’s favorite bird. After guns were invented even fewer people used birds of prey for hunting.

Falcon sometimes attacked farm animals such as chickens and ducks. Many people regarded birds of prey as pests and killed a great number of them-including peregrines. Peregrines also faced other threats.

Egg collectors stole peregrine eggs. Young falcons were stolen from their nests to be trained for falconry.

In the 1960’s, bird watchers noticed that peregrines seemed to be disapearing. In fact, though no one had realized it-peregrines had disapeared from the east coast of the U.S. Scientists slowly discovered certain pesticides used to killing insects were also killing falcons and other birds. The pesticides that kill bugs also makes peregrines nest reproduce unproperly. Some of these pesticides were banned in some areas. DDT was developed for World War II by the US government to help fight diseased spread by mosquitos and lice that often plague troops. After that war it was released for general use and by 1947 it was widely used. Some scientist saw this as evidence that these pesticides had played a part in the decline of peregrines. The poisin had built up in their bodies as they preyed on smaller birds that had eaten insects, seeds, and other plant matter sprayed with DDT. Eventually the poison became so concentrated inside the peregrines’ bodies that they died.

DDT also game peregrines reproducing problems with made their eggs weak and thinner. DDT aslo affected bald eagles, as preys, and brown pelicans, as well as bats and fire flies. All these cheicals almost make peregrines extint if it weren’t for people who cared.

Biologists consider the black footed ferret to be the most endangered mammal in the United States.

Recently however, thanks to aggresive captive breeding and reintroduction programs much progress has been make toward recovering the ferret population.

Ferrets once were found throught the Great Plains, from Texas to southern Saskatchenwan, Canada. Their range extend from the Rocky Mountains east through the Dakotas and south through Nebraska Kansas, Oklahoma, Texas, New Mexico and Arizona. Where prairie dogs were found, so were black footed ferrets. Ferrets eat prairie dogs and live in prairie burrows.

Main causes of the decline in the ferret population included habitat conversion for farming; efforts to eliminate prairie dogs, which competed with livestock for available prairie forage; and the sylvatic plague, a disease which wiped out large numbers of ferrets.

By 1972, biologist believed black-footed ferrets to be extint. From 1972 until 1981, although many ferret sightings were reported the only documented population was found in the 1970’s in South Dakota. Then in 1981 a dog killed on unusual animal on a ranch in Wyoming. The rancher took it to a taxidermist who recognized it as a black footed ferret. This led to the discovery of a small ferret population near Meeteese, Wyoming in 1981. The population increased from 1981 through 1984. At its peak on 1984 nearly 30 ferrets were counted.

During the fall of 1986 and the spring of 1987 the last known wild black-footed

ferrets were taken from the wild and placed in captive breeding facilites.

The captive breeding program is helping ferrets get back to the wild and taking them off the endangered list.

Right whales got their name from the fact that people consider them the right whale to catch. Over the years, people killed huge number of these great whales for their oil and bone for cosmetics, hairspray, and unfortunately more. Unfortunately whales are easy to kill because they are slow swimmers. A thick layer of blubber (fat) under the skin keeps a dead right whale a float, making it easy to retrieve the body.

Because right whales were heavily hunted they are in danger of becoming extinct. Today it’s illegal to kill a right whale and luckily there are people who care and set up programs for saving the sajestic creatures.

The leatherback turtle is the largest of all the living turtles. It gets its name from the leathery skin that covers its carapace, or shell. It could grow up to 4 to 6 feet and can weigh 650 to 1,200 pounds. An average leather back lays 50to 170 eggs and lives in the Atlantic, Pacific, and Indian oceans. They are extremly powerful swimmmers and are found swimming in both temperate and subartic waters. The leatherback can live in these cold waters because, unlike most reptiles, it can generate some internal body heat.

But sadly, these leatherback turtle is in extreme danger of extinction. Althought the adult turtle is rarely hunted, its eggs are eaten by many beachcombing animals, including humans. An even greater threat to the leatherback’s survival is the devlopment of beach resorts on shores that the turtles need for nesting. Every year many of the creatures die after ingesting trash dumed into the ocean. Leatherbacks often mistake plastic bags for jellyfish, their favorite meal. The bagss may suffocate the turtles or block their stomachs causing them to starve to death.

Unfortunately the green turtle is also an endagered sea turtle. It grows up to 4 feet in length commonly weights 250 to 300 pounds; but can weigh up to 600 pounds. The green turtle doesn’t get its name from the colon of its shell but from the greenish tint of its fat. Since ancient times its meat has been considered a luxury food and its eggs are eaten in great quantities in parts of the world. Today, the green turtle is in danger of extinction, although it is protected in a number of countries its numbers are decreasing because it has been widely hunted and its mating places are being destroyed. Though people are killing them some people are helping them, by setting up the Cayman Islands. Its an island where turtles live and humans can’t bother it but sea gull can still get to baby turtles.

Sadly, there so many animals that are endangered and most of them are results from humans. Some animals that had been endangered are most likely extinct suchas Quagga, Great Auk, Pink-headed duck, Aurochs, Dodo, Stellers, Sea Cow, Moa, Passenger and unfortunately more. But some people are helping the animals revive their numbers. Local laws has been set up to protect native species of wild life in various parts of the world for hundreds of years. But now the protection began on an international basis. Other world wide efforts to protect endangered species include international agreement prohibiting the dumping of toxic wastes into the oceans, bans on killing of certain animals, and the refusal on imports or exports products such as skin and furs from endangered species. Thanks to these efforts, it is saving thousands of animals.




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