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Conservation status

The conservation status of a species is an indicator of the likelihood of that endangered species continuing to survive. Many factors are taken into account when assessing the conservation status of a species; not simply the number remaining, but the overall increase or decrease in the population over time, breeding success rates, known threats, and so on. In many areas this is referred to as a red-listed species.

The best-known worldwide conservation status listing is the IUCN (International Union for Conservation of Nature and Natural Resources) Red List, but many more specialized lists exist. The following conservation status categories are used in articles in this encyclopedia. They are loosely based on the IUCN categories.

ˇ Extinct: the last remaining member of the species had died, or is presumed beyond reasonable doubt to have died. Examples: Thylacine, Dodo, Passenger Pigeon.

ˇ Extinct in the wild: captive individuals survive, but there is no free-living, natural population. Examples: Dromedary.

ˇ Critical or critically endangered: faces an extremely high risk of extinction in the immediate future. Examples: Ivory-billed Woodpecker, Arakan Forest Turtle

ˇ Endangered: faces a very high risk of extinction in the near future. Examples: Blue whale, Kings holly, Pink fairy armadillo

ˇ Vulnerable: faces a high risk of extinction in the medium-term. Examples: Cheetah, Bactrian Camel

ˇ Secure or lower risk: no immediate threat to the survival of the species. Examples: Nootka Cypress, Llama

To preserve our present environment and to bring back species on the verge of extinction requires more commitment and money. Fortunately, conservationists are using the Internet and television to educate and inform people about environmental issues.

Several arguments encourage people and countries to adopt conservation methods and pass laws to protect the environment. One point is that plants and animals enhance our world and our environments. Shady trees, colorful butterflies, and singing birds are only a few species that add to the quality of our environments. Second, plants and animals are useful to people. Many plants are medicinal, and some insects protect crops. A third argument is that our survival depends upon a healthy global ecosystem. Without clean air and water, people are more vulnerable to life-threatening diseases.

Whichever argument we use for conserving the environment, one fact is certain: the present rate of destruction cannot continue without the eventual collapse of ecosystems and human populations. Species are as threatened as we are by population growth, pollution, and conflicts over the limited resources.

Some endangered species laws are controversial. Typical areas of controversy include: criteria for placing a species on the endangered species list, and criteria for removing a species from the list once its population has recovered; whether restrictions on land development constitute a "taking" of land by the government; the related question of whether private landowners should be compensated for the loss of use of their land; and obtaining reasonable exceptions to protection laws.



Being listed as an endangered species can backfire, since it could make a species more desirable for collectors and poachers. However, this is usually a spurious argument by those favoring loose protection laws.

Another argument against listing species is the use of the "shoot, shovel, and shut up" method of clearing endangered species from an area of land. Due to the fact that landowners currently may perceive a diminution in value for their land after finding an endangered animal on it, some owners have opted to silently kill and bury the animals, thus removing the problem from their land, but at the same time further reducing the population of an endangered species. It has also been noted that the effectiveness of the Endangered Species Act (ESA), which coined the term "endangered species", has been questioned. Only 15 species have been de-listed to date, and many of those species recovered from the stoppage of practices not related to the European Space Agency, such as the use of DDT. Also, the list has been proven to be somewhat inaccurate as it measures populations of species relative to a certain area, not world-wide. As such, certain animals, such as the Brown Bear and the Gray Wolf have had their populations misrepresented (in those cases, though few still live in the contiguous United States, many roam Alaska and Canada).

 


Date: 2015-12-17; view: 1141


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