CRITERION A. Decrease of the size of the population |
|||
| Main criterion | Subcriterion | Definition | Formula |
| 90 % or a larger decrease of the size of the population for the last 10 years or for 3 generations (CR) 70 % or a larger decrease of the size of the population for the last 10 years or for 3 generations (EN) 50 % or a larger decrease of the size of the population for the last 10 years or for 3 generations (VU) | 1. Decline in the past (observed, estimated, understood or supposed) when the reasons for that are clearly reversible and understandable and discontinued, based on any of the following: | a. direct observation | A1a |
| b. index of abundance | A1b | ||
| c. decrease of the occupied area, the size of the distribution and/or quality of the habitat | A1c | ||
| d. existing or potential level of use (exploitation) | A1d | ||
| e. influence of introduced species, hybridization, pathogens, pollutants, competition or parasites | A1e | ||
| 80 % or a larger decrease of the size of the population for the last 10 years or for 3 generations (CR) 50 % or a larger decrease of the size of the population for the last 10 years or for 3 generations (EN) 30 % or a larger decrease of the size of the population for the last 10 years or for 3 generations (VU) | 2. Decline in the past (observed, estimated, understood or supposed) when the decline or the reasons for it may be not reversible or may be incomprehensible or may be not discontinued, based on any of the following: | a. direct observation | A2a |
| b. index of abundance | A2b | ||
| c. decrease of the occupied area, size of distribution and/or the quality of the habitat | A2c | ||
| d. existing or potential level of use (exploitation) | A2d | ||
| e. influence of introduced species, hybridization, pathogens, pollutants, competition or parasites | A2e | ||
| 80 % or a larger decrease of the size of the population for the last 10 years or for 3 generations (maximum up to 100 years in the future) (CR) 50 % or a larger decrease of the size of the population for the last 10 years or for 3 generations (maximum up to 100 years in the future) (EN) 30 % or a larger decrease of the size of the population for the last 10 years or for 3 generations (a maximum of up to 100 years in the future) (VU) | 3. Decline in the future (assumed or supposed), based on any of the following: | a. direct observation | A3a |
| b. index of abundance | A3b | ||
| c. decrease of the occupied area, size of distribution and/or the quality of the habitat | A3c | ||
| d. existing or potential level of use (exploitation) | A3d | ||
| e. influence of introduced species, hybridization, pathogens, pollutants, competition or parasites | A3e | ||
| 80 % or a larger decrease of the size of the population for the last 10 years or for 3 generations (a maximum of up to 100 years in the future) (CR) 50 % or a larger decrease of the size of the population for the last 10 years or for 3 generations (a maximum of up to 100 years in the future) (EN) 30 % or a larger decrease of the size of the population for the last 10 years or for 3 generations (a maximum of up to 100 years in the future) (VU) | 4. The decline may include both the past and the future (observed, estimated, understood, assumed or supposed) when the decline or the reasons for it may not be reversible or may not be understandable or may not be discontinued, based on any of the following: | a. direct observation | A4a |
| b. index of abundance | A4b | ||
| c. decrease of the occupied area, size of distribution and/or the quality of the habitat | A4c | ||
| d. existing or potential level of use (exploitation) | A4d | ||
| e. influence of introduced species, hybridization, pathogens, pollutants, competition or parasites | A4e | ||
CRITERION B. SMALL REGION OF DISTRIBUTION, fragmentation, decline or fluctuating |
|||
| Major criterion | Subcriterion | Definition | Formula |
| 1. The region of distribution is estimated at <100 sq. km (CR) and at least two of the indicators a, b or c are present The region of distribution is estimated at <5000 sq. km (EN) and at least two of the indicators a, b or c are present The region of distribution is estimated at <20000 sq. km (VU) and at least two of the indicators a, b or c are present | a. The region of distribution is strongly fragmented
or is found:
in one habitat (CR) in ≤ 5 habitats (EN) in ≤ 10 habitats (VU) |
None | B1a |
| b. Continuing decline (observed, understood or assumed, on any of the following: | i. region of distribution | B1bi | |
| ii. occupied area | B1bii | ||
| iii. the area, the scope and/or quality of the habitat | B1biii | ||
| iv. the number of habitats or subpopulations | B1biv | ||
| v. the number of adult individuals | B1bv | ||
| c. Extreme fluctuations of any of the following: | i. region of distribution | B1ci | |
| ii. the occupied area | B1cii | ||
| iii. the number of habitats or subpopulations | B1ciii | ||
| iv. the number of adult individuals | B1civ | ||
| 2. The area occupied is estimated at less than 10 sq. km (CR) and the estimate shows that at least two of a-с are met: The area occupied is estimated at less than 500 sq. km (EN) and the estimate shows that at least two of a-с are met: The area occupied is estimated at less than 2000 sq. km (VU) and the estimate shows that at least two of a-с are met: | a. The region of distribution is strongly fragmented or is found: in one habitat (CR) in ≤ 5 habitats (EN) in ≤ 10 habitats (VU) |
None | B2a |
| b. Continuing decline (observed, understood or assumed, on any of the following: | i. region of distribution | B2bi | |
| ii. occupied area | B2bii | ||
| iii. the area, the scope and/or the quality of the habitat | B2biii | ||
| iv. the number of habitats or subpopulations | B2biv | ||
| v. the number of adult individuals | B2bv | ||
| c. Extreme fluctuations of any of the following: | i. region of distribution | B2ci | |
| ii. occupied area | B2cii | ||
| iii. the number of habitats or subpopulations | B2ciii | ||
| iv. the number of adult individuals | B2civ | ||
CRITERION С. SMALL POPULATIONS declining or fluctuating |
|||
| Major criterion | Subcriterion | Definition | Formula |
| The size of the population is estimated at less than 250 adult individuals (CR) and/or: The size of the population is estimated at less than 2500 adult individuals (EN) and/or: The size of the population is estimated at less than 10000 adult individuals (VU) and/or: | 1. Estimated is a continuing decline of ≥ 25 % within 3 years or 1 generation (CR), maximum up to 100 years in the future Estimated is a continuing decline of ≥ 20 % within 5 years or 2 generations (EN), maximum up to 100 years in the future Estimated is a continuing decline of ≥ 10 % within 10 years or 3 generations (VU), maximum up to 100 years in the future |
None | C1 |
| 2. Continuing decline (estimated, assumed or understood) of the number of adult individuals and at least one of the following (a-b) is present: | ai. all subpopulations ≤ 50 (CR) all subpopulations ≤ 250 (EN) all subpopulations ≤ 1000 (VU) |
C2ai | |
| aii. ≥ 90% adult individuals are in one subpopulation (CR) ≥ 90% of the adult individuals are in one subpopulation (EN) all adult individuals are in one subpopulation (VU) |
C2aii | ||
| b. Extreme fluctuations in the numbers of adult individuals | C2b | ||
CRITERION D1. Very small populations |
|||
| The size of the population is estimated at less than 50 adult individuals The size of the population is estimated at less than 250 adult individuals The size of the population is estimated at less than 1000 adult individuals | None | None | D1 |
CRITERION D2. Very small area of distribution |
|||
| The area occupied is estimated at less than 20 sq. km. or typically occupied habitats are less than 6 (only VU – capable of becoming CR or EX within a very short time) | None | None | D2 |
CRITERION E. Quantitative analyses |
|||
| 20 % probability of extinction in nature in the following 20 years or five generations (EN), whichever of the two is longer (a maximum of up to 100 years) 10 % probability of extinction in nature during the next 100 years (VU) | E | ||