The Red Data Book p4rg

 The

IUCN (International Union for the Conservation of Nature and Natural Resources) maintains an international list, published as the Red Data Book.  A Red Data Book contains lists of species whose continued existence is threatened. Species are classified into different categories of perceived risk.  Each Red Data Book usually deals with a specific group of animals or plants (reptiles, insects, mosses).

 In

1994, IUCN adopted a revised set of Red List categories prepared by the IUCN Species Survival Commission (SSC). There are eight categories and three sub-categories  The IUCN Red List Categories and Criteria are intended to be an easily and widely understood system for classifying species at high risk of global extinction.  The general aim of the system is to provide an explicit, objective framework for the classification of the broadest range of species according to their extinction risk

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Species are classified in nine groups, set through criteria such as rate of decline, population size, area of geographic distribution, and degree of population and distribution fragmentation. Extinct (EX) – No known individuals remaining. Extinct in the Wild (EW) – Known only to survive in captivity, or as a naturalized population outside its historic range. Critically Endangered (CR) – Extremely high risk of extinction in the wild. Endangered (EN) – High risk of extinction in the wild. Vulnerable (VU) – High risk of endangerment in the wild. Near Threatened (NT) – Likely to become endangered in the near future. Least Concern (LC) – Lowest risk. Does not qualify for a more at risk category. Widespread and abundant taxa are included in this category. Data Deficient (DD) – Not enough data to make an assessment of its risk of extinction. Not Evaluated (NE) – Has not yet been evaluated against the criteria.

 CRITICALLY

ENDANGERED (CR)  A taxon is Critically Endangered when it is facing an extremely high risk of extinction in the wild in the immediate future,  A) Population reduction in the form of either of the following:  1) An observed, estimated, inferred or suspected reduction of at least 80% over the last 10 years or three generations, whichever is the longer. 2) A reduction of at least 80%, projected or suspected to be met within the next 10 years or three generations, whichever is the longer.

 B)Extent of occurrence estimated to be 100 km2 or area of occupancy stimated

less than to be less

than 10 km2  C) Population estimated to number less than 250 mature individuals  D) Population estimated to number less than 50 mature individuals.  E) Quantitative analysis showing the probability of extinction in the wild is at least 50% within 10 years or three generations, whichever is the longer.

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ENDANGERED (EN)

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A taxon is Endangered when it is not Critically Endangered but is facing a very high risk of extinction in the wild in the near future. A) Population reduction in the form of either of the following: 1) An observed, estimated, inferred or suspected reduction of at least 50% over the last 10 years or three generations, whichever is the longer 2) A reduction of at least 50%, projected or suspected to be met within the next 10 years or three generations, whichever is the longer. B) Extent of occurrence estimated to be less than 5000 km2 or area of occupancy estimated to be less than 500 km2. C) Population estimated to number less than 2500 mature individuals D) Population estimated to number less than 250 mature individuals. E) Quantitative analysis showing the probability of extinction in the wild is at least 20% within 20 years or five generations, whichever is the longer.

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VULNERABLE (VU) A taxon is Vulnerable when it is not Critically Endangered or Endangered but is facing a high risk of extinction in the wild in the medium-term future,

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A) Population reduction in the form

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1) An observed, estimated, inferred or suspected reduction of at least 20% over the last 10 years or three generations, whichever is the longer 2) A reduction of at least 20%, projected or suspected to be met within the next ten years or three generations, whichever is the longer B) Extent of occurrence estimated to be less than 20,000 km2 or area of occupancy estimated to be less than 2000 km2 C) Population estimated to number less than 10,000 mature individuals D) Population very small or restricted in the form of : 1) Population estimated to number less than 1000 mature individuals E) Quantitative analysis showing the probability of extinction in the wild is at least 10% within 100 years

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http://www.owls.org/Information/data.htm http://www.iucnredlist.org/ http://www.iucnredlist.org/documents/redlist_cats_crit_en.pdf http://www.iucnredlist.org/documents/reg_guidelines_en.pdf http://www.iucnredlist.org/technical-documents/categoriesand-criteria/1994-categories-criteria http://www.nationalredlist.org/site.aspx?pageid=123 http://www.nationalredlist.org/site.aspx?pageid=108 http://www.iucnredlist.org/photos/2012 http://www.iucnredlist.org/about/summarystatistics#How_many_threatened http://www.nytimes.com/interactive/2012/06/01/opinion/sunday /are-we-in-the-midst-of-a-sixth-massextinction.html?ref=sunday