Definition
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters.
Basics
An endangered species is a group (population) of plants, animals or other organisms that is in danger of becoming extinct. This could happen because there are few of that animal left, its predators have grown in number, or the climate that it lives in is changing, or the places it lives in have been destroyed. The World Conservation Union (IUCN) has worked out that endangered species are 40% of all organisms.
Many countries have laws to protect these plants and animals. These laws can save species by stopping hunting, land development or making parks and reserves. Only a few plants and animals at risk of extinction are put on the lists and get legal protection. Many more species become extinct, or will become extinct, without people knowing about it.
Some of the animals that are listed as endangered are:
- Blue Whale
- Giant Panda
- Snow Leopard
- African Wild Dog
- Tiger
- Albatross
- Crowned Solitary Eagle
Topics of Interest
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters. Also it could mean that due to deforestation there may be a lack of food and/or water. The International Union for Conservation of Nature (IUCN) has calculated the percentage of endangered species as 40 percent of all organisms based on the sample of species that have been evaluated through 2006. (Note: the IUCN groups all threatened species for their summary purposes.) Many nations have laws offering protection to conservation reliant species: for example, forbidding hunting, restricting land development or creating preserves. Only a few of the many species at risk of extinction actually make it to the lists and obtain legal protection. Many more species become extinct, or potentially will become extinct, without gaining public notice.
The conservation status of a species is an indicator of the likelihood of that species remaining extant either in the present day or the near future. 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.
The IUCN Red List of Threatened Species is the best-known worldwide conservation status listing and ranking system. The system divides threatened species into three categories: Critically Endangered (CR), Endangered (EN), and Vulnerable (VU). Also listed are the documented extinctions that have occurred since 1500 AD and taxa that are extinct in the wild. Lower risk taxa are also divided into categories.
Consumer guides for seafood, such as Seafood Watch, generally divide fish and other sea creatures into three categories, analogous to conservation status categories:
- Red ("say no" or "avoid")
- Yellow or orange ("think twice", "good alternatives" or "some concerns")
- Green ("best seafood choices").
The categories do not simply reflect the imperilment of individual species, but also consider the environmental impacts of how and where they are fished, such as through bycatch or ocean bottom trawlers. Often groups of species are assessed rather than individual species (e.g. Bluefin tuna or squid).
The Marine Conservation Society has 5 levels of ratings for seafood species, as displayed on their Fishonline website.
A Biodiversity Action Plan (BAP) is an internationally recognized program addressing threatened species and habitats and is designed to protect and restore biological systems. The original impetus for these plans derives from the 1992 Convention on Biological Diversity (CBD). As of 2009, 191 countries have ratified the CBD, but only a fraction of these have developed substantive BAP documents.
In paleontology, a Lazarus taxon (plural taxa) is a taxon that disappears from one or more periods of the fossil record, only to appear again later. The term refers to an account in the Gospel of John, in which Jesus miraculously raised Lazarus from the dead. Lazarus taxa are observational artifacts that appear to occur either because of (local) extinction, later resupplied, or as a sampling artifact. If the extinction is conclusively found to be total (global or worldwide) and the supplanting species is not a lookalike (an Elvis species), the observational artifact is overcome. The fossil record is inherently imperfect (only a very small fraction of organisms become fossilized) and contains gaps not necessarily caused by extinction, particularly when the number of individuals in a taxon becomes very low. If these gaps are filled by new fossil discoveries, a taxon will no longer be classified as a Lazarus taxon.
The Endangered Species Act of 1973 (7 U.S.C. § 136, 16 U.S.C. § 1531 et seq. , ESA) is one of the dozens of United States environmental laws passed in the 1970s. As stated in section 2 of the act, it was designed to protect critically imperiled species from extinction as a "consequence of economic growth and development untempered by adequate concern and conservation."
Organisms with a conservation status of critically endangered have an extremely high risk of becoming extinct in the wild or completely in the immediate future.
Source: Wikipedia (All text is available under the terms of the GNU Free Documentation License and Creative Commons Attribution-ShareAlike License.)
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