Guidelines for Application of the Revised IUCN Threat Categories to Bryophytes

The new IUCN threat categories include many numerical thresholds that require quantitative data. Since such data are rare for bryophytes, the evaluation against the threat categories must often be done by inference from the available data. The most relevant data that can be used for bryophytes are population decline, present distribution and total population size, number of sites, and estimated loss of relevant habitats over the last 10 years or three generations. For assessing species at a regional level, evidence of an inflow of propagules from outside the Red List region is discussed. The use of the terms 'individual', 'fragmentation', 'location' and 'generation time' is also discussed.