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The IUCN Red List Criteria. THREATENED CATEGORIES. A. Population reduction. Restricted geographic range. B. Critically Endangered (CR). Small population size & decline. C. Quantitative thresholds. Endangered (EN). Very small or restricted population. D. Vulnerable (VU). E.
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THREATENED CATEGORIES A Population reduction Restricted geographic range B Critically Endangered (CR) Small population size & decline C Quantitative thresholds Endangered (EN) Very small or restricted population D Vulnerable (VU) E Quantitative analysis Nature of the Criteria CRITERIA
Why use multiple criteria? Not all the criteria are appropriate to all taxa. • All taxa being assessed must be evaluated against each criterion. • Meeting any one of the criteria qualifies a taxon for listing at that level of threat • All criteria met at the highest level of threat should be listed.
Population Size Time Criterion A Past, present or future population reduction
Criterion A • Based on any of four criteria: • A1: Population reduction inpastandcauses of decline now ceased • A2:Population reduction inpastandcauses of decline ongoing • A3:Population reduction expected infuture • A4:Population reduction inpast AND future
Reduction Criterion A Managed harvest species (e.g., fisheries) Taxa that are the target of large-scale harvesting may show a decline in population size due to intentional management actions. Such taxa could be assigned a threatened status under criterion A. Concern has been expressed that such a listing might not reflect extinction risk, especially if the decline is a consequence of a management plan designed to maximize sustainable yield from a fishery. BUT, if the fishery is managed effectively, although it currently shows symptoms consistent with endangerment, the population will eventually stabilize at a target level and the decline will end, such that the taxon would then no longer qualify for listing. If declines continued, there would be good reason for concern, and the listing would still apply. Taxa that are targeted by sustainably managed fisheries should be assessed under criterion A1, where the higher thresholds make it less likely that they will be classified as threatened.
Present Last 10 years or 3 generations (whichever is longer) 30% Vulnerable 50% Vulnerable 50% Endangered 70% Endangered 90% Critically Endangered 80% Critically Endangered Present Last 10 years or 3 generations (whichever is longer) Criterion A1past reduction & causes understood & ceased & reduction is reversible Criterion A2past reduction & causes may not be understood or may not have ceased or reduction may not be reversible
Present Next 10 years or 3 generations (whichever is longer up to a maximum of 100 years) 30% Vulnerable 30% Vulnerable 50% Endangered 50% Endangered 80% Critically Endangered 80% Critically Endangered Present 10 years or 3 generations (whichever is longer, up to a maximim of 100 years in the future) including some time in the past AND in the future Sub-criterion A3future decline Sub-criterion A4past & future
introduced taxa • hybridization • pathogens • pollutants • competitors • parasites • For ALL the criteria (A1–A4), rate of population reduction should be based on any of: • (a) Direct observation (not for sub-criterion A3 – future reduction) • (b) An index of abundance appropriate to 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:
Criterion B Restricted geographic range and fragmentation, continuing decline or extreme fluctuations
Based on either of two sub-criteria: • B1: Estimated extent of occurrence • AND / OR • B2: Estimated area of occupancy • ANDat leastTWOof a-c: • a. Severely fragmented or few locations • b. Continuing decline • c. Extreme fluctuations Criterion B
< 10 km² < 500 km² < 2,000 km² Criterion B Subcriterion B1 Extent of occurrence estimated to be: Subcriterion B2 Area of occupancy estimated to be: CR < 100 km² < 5,000 km² EN < 20,000 km² VU
b. Continuing decline in any of the following: • EOO • AOO • Area, extent and/or quality of habitat • # locations or subpopulations • # mature individuals • c. Extreme fluctuation in any of the following: • EOO • AOO • # locations or subpopulations • # mature individuals CR 1 Criterion B • AND at least TWO of a, b or c: a. Severely fragmented or # locations: 5 EN 10 VU
Popondetta Blue-eye (Pseudomugil connieae) Vulnerable B1ab(iii) Justification: Assessed as Vulnerable due to its restricted extent of occurrence, which is 15,927 km². This species occurs in only three locations, (three river systems). Two of these locations are threatened by urban encroachment. In addition, P. connieae is threatened by a continuing decline in habitat quality, due to logging, and an increase in agriculture and urbanization in the region of Popondetta.
Criterion B Vulnerable B1ab(iii) < 10 km² < 500 km² < 2,000 km² Subcriterion B1 Extent of occurrence estimated to be: Subcriterion B2 Area of occupancy estimated to be: CR < 100 km² < 5,000 km² EN < 20,000 km² VU
b. Continuing decline in any of the following: • EOO • AOO • Area, extent and/or quality of habitat • # locations or subpopulations • # mature individuals • c. Extreme fluctuation in any of the following: • EOO • AOO • # locations or subpopulations • # mature individuals CR 1 Criterion B Vulnerable B1ab(iii) • AND at least TWO of a, b or c: a. Severely fragmented or # locations: 5 EN 10 VU
Gorgeted Puffleg (Eriocnemis isabellae) Critically Endangered B1ab(iii)+2ab(iii) Justification:This newly described species qualifies as Critically Endangered because it is known from a single location and has an extremely small Area of Occupancy within which habitat quality is continuing to decline owing to conversion for agriculture (particularly coca cultivation).
Criterion B B1ab(iii)+B2ab(iii) < 10 km² < 500 km² < 2,000 km² Subcriterion B1 Extent of occurrence estimated to be: Subcriterion B2 Area of occupancy estimated to be: CR < 100 km² < 5,000 km² EN < 20,000 km² VU
b. Continuing decline in any of the following: • EOO • AOO • Area, extent and/or quality of habitat • # locations or subpopulations • # mature individuals • c. Extreme fluctuation in any of the following: • EOO • AOO • # locations or subpopulations • # mature individuals CR 1 Criterion B B1ab(iii)+B2ab(iii) • AND at least TWO of a, b or c: a. Severely fragmented or # locations: 5 EN 10 VU
Extinct Criterion C Small population size and continuing decline
CR < 250 mature individuals < 2,500 mature individuals < 10,000 mature individuals Criterion C Thresholds for criterion C Population size is estimated at: EN VU
Criterion D Very small or restricted population
< 50 mature individuals CR D1.Total current population size estimated as: Criterion D Criterion D is split into D for the CR and EN categories; and D1 and D2 for the VU category. D. Total current population size estimated as: NOTE:for the VU D2, there should be a plausible threat that is likely to rapidly affect the population. < 250 mature individuals EN D2.The population has a very restricted AOO(typically <20 km²) or is known from very few locations(typically ≤5). < 1,000 mature individuals VU
= oh ohh! Criterion E Quantitative analysis
50% 20% Critically Endangered Endangered Vulnerable 10% Criterion E Based on quantitative analysis showing a probability of extinction in the wild is at least: Within 10 years or 3 generations Within 20 years or 5 generations Within 100 years Up to a maximum of 100 years in the future
Lucy Harrison Program Officer iucnshark@gmail.com