Table showing IUCN Red List criteria

Type of criteria Main criteria Sub-criteria Qualifiers Codes
A. RAPID POPULATION DECLINE Reduction >80% in 10 years or 3 generations (CR) involving either 1 or 2:


Reduction >50% in 10 years or 3 generations (EN) involving either 1 or 2:


Reduction >20% in 10 years or 3 generations (VU) involving either 1 or 2:		 1. Decline which has happened (observed, estimated, inferred or suspected) based on a-e opposite: a. Direct observation A1a
b. Index of abundance A1b
c. Decline in extent of occurrence, area of occupancy, and/or quality of habitat A1c
d. Actual or potential levels of exploitation A1d
e. Effects of introduced taxa, hybridization, pathogens, pollutants, competitors or parasites A1e
2. Decline likely in near future (projected or suspected) based on b-e opposite: b. As b above A2b
c. As c above A2c
d. As d above A2d
e. As e above A2e
B. SMALL RANGE fragmented, declining or fluctuating Extent of occurrence estimated <100 km2 (CR) with any two of 1,2 or 3:

Extent of occurrence estimated <5,000 km2 (EN) with any two of 1, 2 or 3:

Extent of occurrence estimated <20,000 km2 (VU) with any two of 1, 2 or 3:

or

Area of occupancy estimated <10 km2 (CR) with any two of 1, 2 or 3:

Area of occupancy estimated <500 km2 (EN) with any two of 1, 2 or 3:

Area of occupancy estimated <2,000 km2 (VU) with any two of 1, 2 or 3:		 1. Severe fragmentation

or

At 1 location (CR)

At <6 locations (EN)

At <11 locations (VU)		 None B1
2. Continuing decline (observed, inferred or projected) in any of a-e opposite: a. Extent of occurrence B2a
b. Area of occupancy B2b
c. Area, extent and/or quality of habitat B2c
d. Number of locations or subpopulations B2d
e. Number of mature individuals B2e
3. Extreme fluctuations in any of a-d opposite: a. Extent of occurrence B3a
b. Area of occupancy B3b
c. Number of locations or subpopulations B3c
d. Number of mature individuals B3d
C. SMALL POPULATION & DECLINING Population <250 mature individuals (CR) and either 1 or 2




Population <2,500 mature individuals (EN) and either 1 or 2




Population <10,000 mature individuals (VU) and either 1 or 2		 1. Decline >25% in 3 years or 1 generation (CR)

Decline >20% in 5 years or 2 generations (EN)

Decline >10% in 10 years or 3 generations (VU)		 None C1
2. Continuing decline in numbers of mature individuals and population structure (observed, projected or inferred) in form of either a or b opposite: a. Severe fragmentation: all sub pops <50 (CR)

Severe fragmentation: all sub pops <250 (EN)

Severe fragmentation: all sub pops <1,000 (VU)		 C2a
b. All individuals in a single sub pop C2b
D1. VERY SMALL POPULATION Population <50 mature individuals (CR)

Population <250 mature individuals (EN)

Population <1,000 mature individuals (VU)		 None None D1
D2. VERY SMALL RANGE Area of occupancy <100 km2 or <5 locations (VU only) None None D2

Note: As of 2001, the IUCN Red List criteria have been revised. For more details on the IUCN Red List categories and criteria, see IUCN/SSC (1994, 2001) Red List categories and criteria, published by the IUCN Species Survival Commission. For further information, check the Species Survival Commission website


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