Acknowledgements: This publication is part of The 2008 Review of The IUCN Red List of Threatened Species. The IUCN Red List is compiled and produced by the IUCN Species Programme based on contributions from a network of thousands of scientifi c experts around the world. These include members of the IUCN Species Survival Commission Specialist Groups, Red List Partners (currently Conservation Int...

Acknowledgements: This publication is part of The 2008 Review of The IUCN Red List of Threatened Species. The IUCN Red List is compiled and produced by the IUCN Species Programme based on contributions from a network of thousands of scientifi c experts around the world. These include members of the IUCN Species Survival Commission Specialist Groups, Red List Partners (currently Conservation Int...

The IUCN Red List of Threatened Species (www.redlist.org) is a comprehensive list of relative extinction risk for species throughout the world, and it is commonly referenced in the scientific literature. Established in 1963, the IUCN Red List and its Criteria have been revised regularly to make them more scientific and objective. Nevertheless, the aim of the IUCN Red List to establish global st...

Polar Bears (Ursus maritimus) are facing a range of threats that might impact their future population status (see section Threats below). The IUCN Polar Bear Specialist Group (PBSG) regards loss of sea-ice habitat due to climate warming as the most serious threat to future Polar Bear survival. We therefore based our Red List assessment on this threat factor only, recognizing that sea-ice condit...

Low genetic diversity may be associated with an increase in species' extinction risk (Spielman et al. 2004, Frankham 2005). Still, global conservation assessments do not consider relevant genetic-based estimates for evaluating species threat status. Rather, they rely primarily on changes population abundance and range size, the inherent assumption that intra-specific variability is tightly corr...

The newly developed IUCN Red List of Ecosystems is part of a growing toolbox for assessing risks to biodiversity, which addresses ecosystems and their functioning. The Red List of Ecosystems standard allows systematic assessment of all freshwater, marine, terrestrial and subterranean ecosystem types in terms of their global risk of collapse. In addition, the Red List of Ecosystems categories an...

We comment on a recent article by Newton (Environ. Model. Softw. (2010), 25, 15-23), which proposed a method, based on a Bayesian belief networks, for classifying the threat status of species under the IUCN Red List Categories and Criteria, and compared this method to an earlier one that we had developed that is based on fuzzy logic. There are three types of differences between the results of t...