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United Nations Environment Programme | ![]() |
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| World Conservation Monitoring Centre | ||||||||||
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The Criteria for Critically Endangered, Endangered and Vulnerable
The Criteria for Critically Endangered CRITICALLY ENDANGERED (CR) A) Population reduction in the form of either of the following:
b) an index of abundance appropriate for the taxon c) a decline in area of occupancy, extent of occurrence and/or quality of habitat d) actual or potential levels of exploitation e) the effects of introduced taxa, hybridisation, pathogens, pollutants, competitors or parasites. 2) A reduction of at least 80%, projected or suspected to be met within the next ten years or three generations, whichever is the longer, based on (and specifying) any of (b), (c), (d) or (e) above.
2) Continuing decline, observed, inferred or projected, in any of
the following:
b) area of occupancy c) area, extent and/or quality of habitat d) number of locations or subpopulations e) number of mature individuals. 3) Extreme fluctuations in any of the following:
b) area of occupancy c) number of locations or subpopulations d) number of mature individuals. C) Population estimated to number less than 250 mature individuals and either:
2) A continuing decline, observed, projected, or inferred, in numbers of mature individuals and population structure in the form of either:
b) all individuals are in a single subpopulation. E) Quantitative analysis showing the probability of extinction in the
wild is at least 50% within 10 years or 3 generations, whichever is the
longer. ENDANGERED (EN) A) Population reduction in the form of either of the following:
b) an index of abundance appropriate for the taxon c) a decline in area of occupancy, extent of occurrence and/or quality of habitat d) actual or potential levels of exploitation e) the effects of introduced taxa, hybridisation, pathogens, pollutants, competitors or parasites. B) Extent of occurrence estimated to be less than 5000 km2 or area of occupancy estimated to be less than 500 km2, and estimates indicating any two of the following:
2) Continuing decline, inferred, observed or projected, in any of
the following:
b) area of occupancy c) area, extent and/or quality of habitat d) number of locations or subpopulations e) number of mature individuals. 3) Extreme fluctuations in any of the following:
b) area of occupancy c) number of locations or subpopulations d) number of mature individuals.
2) A continuing decline, observed, projected, or inferred, in numbers of mature individuals and population structure in the form of either:
b) all individuals are in a single subpopulation. E) Quantitative analysis showing the probability of extinction in the wild is at least 20% within 20 years or 5 generations, whichever is the longer. The Criteria for Vulnerable VULNERABLE (VU) A) Population reduction in the form of either of the following:
b) an index of abundance appropriate for the taxon c) a decline in area of occupancy, extent of occurrence and/or quality of habitat d) actual or potential levels of exploitation e) the effects of introduced taxa, hybridisation, pathogens, pollutants, competitors or parasites.
B) Extent of occurrence estimated to be less than 20,000 km2 or area of occupancy estimated to be less than 2000 km2, and estimates indicating any two of the following:
2) Continuing decline, inferred, observed or projected, in any of
the following:
b) area of occupancy c) area, extent and/or quality of habitat d) number of locations or subpopulations e) number of mature individuals.
b) area of occupancy c) number of locations or subpopulations d) number of mature individuals. C) Population estimated to number less than 10,000 mature individuals and either:
2) A continuing decline, observed, projected, or inferred, in numbers of mature individuals and population structure in the form of either:
b) all individuals are in a single subpopulation.
2) Population is characterised by an acute restriction in its area of occupancy (typically less than 100 km2) or in the number of locations (typically less than 5). Such a taxon would thus be prone to the effects of human activities (or stochastic events whose impact is increased by human activities) within a very short period of time in an unforeseeable future, and is thus capable of becoming Critically Endangered or even Extinct in a very short period. E) Quantitative analysis showing the probability of extinction in the
wild is at least 10% within 100 years. |
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