The mission of the U. Fish and Wildlife Service is working with others to conserve, protect, and enhance fish, wildlife, plants, and their habitats for the continuing benefit of the American people. Endangered - any species that is in danger of extinction throughout all or a significant portion of its range;. Threatened - any species that is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.
Endangered species are at the brink of extinction now. Threatened species are likely to be at the brink in the near future. All of the protections of the Act are provided to endangered species. Many, but not all, of those protections also are available to threatened species. Endangered Species 1 Population reduction rate A species is classified as endangered when its population has declined between 50 and 70 percent. A species is classified as endangered when its population has declined at least 70 percent and the cause of the decline is known.
A species is also classified as endangered when its population has declined at least 50 percent and the cause of the decline is not known. When a species population declines by at least 20 percent within five years or two generations, it is also classified as endangered. Endangered Species: Siberian Sturgeon The Siberian sturgeon Acipenser baerii is a large fish found in rivers and lakes throughout the Siberian region of Russia. The Siberian sturgeon is a benthic species.
Benthic species live at the bottom of a body of water. The Siberian sturgeon is an endangered species because its total population has declined between 50 and 80 percent during the past 60 years three generations of sturgeon. Overfishing, poach ing, and dam construction have caused this decline. It is an endangered species because it has a very small population.
The bird is only found on a single island, meaning both its extent of occurrence and area of occupancy are very small. The Tahiti reed-warbler is also endangered because of human activity. The bird nests in bamboo and feeds on flowers and insects that live there. As development and invasive species such as Miconia destroy the bamboo forests, the population of Tahiti reed-warblers continues to shrink.
Ebony is an endangered species because many biologists calculate its probability of extinction in the wild is at least 20 percent within five generations. Ebony is threatened due to overharvest ing. Ebony trees produce a very heavy, dark wood. When polished, ebony can be mistaken for black marble or other stone.
For centuries, ebony trees have been harvested for furniture and sculptural uses such as chess pieces. Most ebony, however, is harvested to make musical instruments such as piano key s and the fingerboard s of stringed instruments. A species is classified as critically endangered when its population has declined at least 90 percent and the cause of the decline is known. A species is also classified as endangered when its population has declined at least 80 percent and the cause of the decline is not known.
A species is also classified as critically endangered when the number of mature individuals declines by at least 25 percent within three years or one generation, whichever is longer. It is critically endangered because its extent of occurrence is less than square kilometers 39 square miles. The major threat to this species is loss of its cloud forest habitat.
People are clearing forests to create cattle pasture s. The Transcaucasian racerunner is a critically endangered species because of a huge population decline, estimated at more than 80 percent during the past 10 years. Threats to this species include the salination , or increased saltiness, of soil. Fertilizers used for agricultural development seep into the soil, increasing its saltiness.
Racerunners live in and among the rocks and soil, and cannot adapt to the increased salt in their food and shelter. The racerunner is also losing habitat as people create trash dumps on their area of occupancy.
Critically Endangered Species: White Ferula Mushroom The white ferula mushroom Pleurotus nebrodensis is a critically endangered species of fungus. The mushroom is critically endangered because its extent of occurrence is less than square kilometers 39 square miles. It is only found in the northern part of the Italian island of Sicily, in the Mediterranean Sea. The leading threats to white ferula mushrooms are loss of habitat and overharvesting.
White ferula mushrooms are a gourmet food item. Farmers and amateur mushroom hunters harvest the fungus for food and profit. Extinct In The Wild A species is extinct in the wild when it only survives in cultivation plants , in captivity animals , or as a population well outside its established range.
A species may be listed as extinct in the wild only after years of surveys have failed to record an individual in its native or expected habitat. Extinct in the Wild: Scimitar-horned Oryx The scimitar-horned oryx Oryx dammah is a species of antelope with long horns. Its range extends across northern Africa. The scimitar-horned oryx is listed as extinct in the wild because the last confirmed sighting of one was in Captive herds are now kept in protected areas of Tunisia, Senegal, and Morocco.
Scimitar-horned oryxes are also found in many zoos. Extinct in the Wild: Black Soft-shell Turtle The black soft-shell turtle Nilssonia nigricans is a freshwater turtle that exists only in one man-made pond, at the Baizid Bostami Shrine near Chittagong, Bangladesh. The to turtles that live at the pond rely entirely on humans for food.
Until , black soft-shell turtles lived throughout the wetland s of the Brahmaputra River, feeding mostly on freshwater fish. Unlike other animals that are extinct in the wild, black soft-shell turtles are not found in many zoos. The reptiles are considered to be the descendants of people who were miraculously turned into turtles by a saint during the 13th century.
Extinct in the Wild: Mt. Kaala Cyanea The Mt. Kaala cyanea Cyanea superba is a large, flowering tree native to the island of Oahu, in the U. The Mt. Kaala cyanea has large, broad leaves and fleshy fruit. The tree is extinct in the wild largely because of invasive species. Non-native plants crowded the cyanea out of its habitat, and non-native animals such as pigs, rats, and slugs ate its fruit more quickly than it could reproduce.
Kaala cyanea trees survive in tropical nurseries and botanical garden s. Many botanists and conservationists look forward to establishing a new population in the wild. Extinct A species is extinct when there is no reasonable doubt that the last remaining individual of that species has died. The last specimen of the Cuban macaw was collected in This insect, whose long, segmented body resembled a tree limb, is only known through a single specimen, collected more than years ago.
During the 20th century, Singapore experienced rapid development. Almost the entire jungle was cleared, depriving the insect of its habitat. Peas and peanuts are smaller types of legumes. Habitat loss from development in the 20th century is the main reason the tree went extinct in the wild. A single specimen survived at the Royal Botanical Garden in Peradeniya, Sri Lanka, until , when that, too, was lost. Endangered Species and People When a species is classified as endangered, governments and international organization s can work to protect it.
Individuals and organizations that break these laws may face huge fine s. Because of such actions, many species have recovered from their endangered status. The brown pelican was taken off the endangered species list in , for instance. It is the state bird of the U. In , the number of brown pelicans in the wild was estimated at 10, The bird was classified as vulnerable. During the s and s, governments and conservation groups worked to help the brown pelican recover.
Young chicks were reared in hatch ing sites, then released into the wild. Human access to nesting sites was severely restricted. The pesticide DDT , which damaged the eggs of the brown pelican, was banned. During the s, the number of brown pelicans soared.
The bird, whose population is now in the hundreds of thousands, is now in the category of least concern. Lonesome George Until , Lonesome George was the most endangered species on the planet. He was the only living species of Pinta Island tortoise known to exist. On June 25, , Lonesome George died, leaving one more extinct species in the world. Convention on Biological Diversity The Convention on Biological Diversity is an international treaty to sustain and protect the diversity of life on Earth.
This includes conservation, sustainability, and sharing the benefits of genetic research and resources.
The period ended with extinction of the dinosaurs and the rise of mammals. The last ice age peaked about 20, years ago. Also called glacial age. Well, what is an endangered animal then? Endangered animals and plants are at risk of extinction - there are so few of them that they might soon be wiped out altogether. Although some plants and animals have always evolved more successfully than others, human activity is changing the world in such a way that many more animals and plants are endangered than would otherwise be.
Find out about the extinct and endangered animals in the Museum. Dodo Coelacanth Thylacine Blue whale Golden toad Giant panda Passenger pigeon Schaus' swallowtail Go to the Homepage to find out about hippos and the causes of extinction.
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