There are several ways to get protection under the act, says Noah Greenwald , the endangered species director for the Center for Biological Diversity, an environmental group based in Tucson, Arizona. The first way is the that the U. Fish and Wildlife Service, the agency tasked with enforcing the act, can designate a species as in need of protection.
Then, the agency can either create a proposed rule for its protection or put it on a candidate list. If the service proposes a rule, the public has a period in which they can comment on it, either to support the proposal or raise concerns. If everything goes smoothly, the species will receive official listing as endangered or threatened within a year of the proposal.
The second way a species can gain protection: A group like the Center for Biological Diversity, or even a private citizen, can propose a species for consideration.
If the petition passes this first test, then the agency has a year to decide whether the species fits in one of these three categories: warranted, not warranted, or warranted but precluded. In this case, the species is often put on the candidate list, to be re-evaluated every year. Read more: Inside the effort to kill protections for endangered animals.
This is a species that may be gone from the wild now. As of there were only in captivity. Take for example the trispot darter—a small, handsome finned fish found only in a few places in the southeastern U.
It was first considered to be listed as threatened or endangered in , but it was not immediately reviewed by the service.
The fish remained a candidate until , when the service determined that the fish could warrant protection, but scientific data was lacking. However, administrative changes two years later removed it from consideration altogether.
In , environmental groups including the Center for Biological Diversity petitioned the service to list it. On the federal level, the endangered species list is managed under the Endangered Species Act. Under the ESA, the federal government has the responsibility to protect endangered species species that are likely to become extinct throughout all or a large portion of their range , threatened species species that are likely to become endangered in the near future , and critical habitat areas vital to the survival of endangered or threatened species.
The Endangered Species Act has lists of protected plant and animal species both nationally and worldwide. When a species is given ESA protection, it is said to be a "listed" species. The Endangered Species Act is very important because it saves our native fish, plants, and other wildlife from going extinct. Once gone, they're gone forever, and there's no going back. Losing even a single species can have disastrous impacts on the rest of the ecosystem, because the effects will be felt throughout the food chain.
From providing cures to deadly diseases to maintaining natural ecosystems and improving overall quality of life, the benefits of preserving threatened and endangered species are invaluable. When the U.
In order to be listed as a candidate, a species has to qualify for protected status under the Endangered Species Act. Whether or not a species is listed as endangered or threatened then depends on a number of factors, including the urgency and whether adequate protections exist through other means. When deciding whether a species should be added to the Endangered Species List, the following criteria are evaluated:.
If the answer to one or more of the above questions is yes, then the species can be listed under the Endangered Species Act. Endangered is a word used to describe plant and animal species that are not doing very well. Animals usually become endangered because of over hunting or the destruction of their habitat. An animal that is endangered is close to extinction, meaning there aren't very many of that type of animal left in the world.
Human activity can also contribute to a loss of habitat. Development for housing, industry , and agriculture reduces the habitat of native organisms. This can happen in a number of different ways. Development can eliminate habitat and native species directly. In the Amazon rain forest of South America, developers have cleared hundreds of thousands of acres. The Amazon rain forest is cleared for cattle ranch es, logging , and urban use. Development can also endanger species indirectly.
Some species, such as fig trees of the rain forest, may provide habitat for other species. As trees are destroyed, species that depend on that tree habitat may also become endangered. Tree crown s provide habitat in the canopy , or top layer, of a rainforest. Plants such as vines, fungi such as mushrooms, and insects such as butterflies live in the rain forest canopy.
So do hundreds of species of tropical birds and mammals such as monkeys. As trees are cut down, this habitat is lost. Species have less room to live and reproduce. Loss of habitat may happen as development takes place in a species range. Many animals have a range of hundreds of square kilometers. The mountain lion of North America, for instance, has a range of up to 1, square kilometers square miles.
To successfully live and reproduce, a single mountain lion patrol s this much territory. That means the habitat can support fewer mountain lions.
Because enormous parts of the Sierra Nevada, Rocky, and Cascade mountain ranges remain undeveloped, however, mountain lions are not endangered. Loss of habitat can also lead to increased encounters between wild species and people. As development brings people deeper into a species range, they may have more exposure to wild species.
Poisonous plants and fungi may grow closer to homes and schools. Wild animals are also spotted more frequent ly. These animals are simply patrolling their range, but interaction with people can be deadly. Polar bears, mountain lions, and alligators are all predators brought into close contact with people as they lose their habitat to homes, farms, and businesses.
As people kill these wild animals, through pesticide s, accidents such as collisions with cars, or hunting, native species may become endangered. Loss of Genetic Variation Genetic variation is the diversity found within a species. Genetic variation allows species to adapt to changes in the environment. Usually, the greater the population of a species, the greater its genetic variation. Inbreed ing is reproduction with close family members. Groups of species that have a tendency to inbreed usually have little genetic variation, because no new genetic information is introduced to the group.
Disease is much more common, and much more deadly, among inbred groups. Inbred species do not have the genetic variation to develop resistance to the disease. For this reason, fewer offspring of inbred groups survive to maturity. Loss of genetic variation can occur naturally. Cheetah s are a threatened species native to Africa and Asia. These big cat s have very little genetic variation.
Biologist s say that during the last ice age , cheetahs went through a long period of inbreeding. As a result, there are very few genetic differences between cheetahs. They cannot adapt to changes in the environment as quickly as other animals, and fewer cheetahs survive to maturity.
Cheetahs are also much more difficult to breed in captivity than other big cats, such as lions. Human activity can also lead to a loss of genetic variation. Overhunt ing and overfish ing have reduced the populations of many animals.
Reduced population means there are fewer breeding pairs. A breeding pair is made up of two mature members of the species that are not closely related and can produce healthy offspring. With fewer breeding pairs, genetic variation shrinks.
Monoculture , the agricultural method of growing a single crop , can also reduce genetic variation. Modern agribusiness relies on monocultures. Almost all potatoes cultivate d, sold, and consumed, for instance, are from a single species, the Russet Burbank.
Potatoes, native to the Andes Mountains of South America, have dozens of natural varieties. The genetic variation of wild potatoes allows them to adapt to climate change and disease. For Russet Burbanks, however, farmers must use fertilizer s and pesticides to ensure healthy crops because the plant has almost no genetic variation. Plant breeders often go back to wild varieties to collect genes that will help cultivated plants resist pests and drought, and adapt to climate change.
However, climate change is also threatening wild varieties. That means domesticated plants may lose an important source of traits that help them overcome new threats. The Red List has seven levels of conservation: least concern, near threatened, vulnerable, endangered, critically endangered, extinct in the wild, and extinct. Each category represents a different threat level.
Species that are not threatened by extinction are placed within the first two categories—least concern and near-threatened. Those that are most threatened are placed within the next three categories, known as the threatened categories —vulnerable, endangered, and critically endangered. Those species that are extinct in some form are placed within the last two categories—extinct in the wild and extinct. Classifying a species as endangered has to do with its range and habitat, as well as its actual population.
For this reason, a species can be of least concern in one area and endangered in another. The gray whale, for instance, has a healthy population in the eastern Pacific Ocean, along the coast of North and South America. The population in the western Pacific, however, is critically endangered.
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