IUCN Red List
P. Meier
The IUCN Red List of Threatened SpeciesTM, known as the IUCN Red List, is the world’s most comprehensive inventory of the global conservation status of plant, fungi and animal species. It is used to assess the state of the world’s biodiversity. The IUCN Red List provides information and analyses on the status, trends and threats to species. The goal is to inform and catalyse action for biodiversity conservation and policy change. It aims to convey the urgency and scale of conservation problems to the public and policy makers, and to motivate the global community to reduce species extinctions.
The IUCN Red List uses a set of criteria to evaluate the extinction risk of taxa by classifying them into one of nine Red List Categories based on five Criteria (Figure 1). The IUCN Red List has a strong scientific base. Assessments for the Red List are done by the world’s leading scientists and go through a thorough review process. The IUCN Red List is not just a list and does not only evaluate the extinction risk of a species, but also provides important background information of the status of the taxa in a global or regional perspective such as on its range, population size, habitats and ecology, use and trade, threats and conservation actions. It establishes a baseline from which to monitor the future status of a species. The periodic assessment process for the IUCN Red List is important to identify improvements and aggravations of a species' situation. In this regard, the IUCN Red List helps to define the most urgent conservation measures for a species and is widely used to inform and influence biodiversity conservation. Ultimately, the IUCN Red List informs policy and provides information to international agreements such as the Convention on Biological Diversity (CBD) and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). However, the IUCN Red List is not a final list of species that are priorities for conservation action and some species not listed can be of high conservation priority.
The IUCN Red List is an online scientific journal and open source. It is used by government agencies, wildlife departments, conservation-related non-governmental organizations (NGOs), natural resource planners, educational organizations, and many others interested in reversing, or at least halting the decline in biodiversity.
IUCN Red List assessments can be carried out by anyone who has sufficient knowledge of a species. The majority of the assessments are however conducted by the members of the IUCN Species Survival Commission (SSC), Red List Authorities, Red List Partners or specialists working on specific IUCN projects.
Global assessments on cat species or subspecies are coordinated by the Red List Authority of the Cat SG. For a global assessment of a subspecies, the species has to first be assessed. Generally, (re)assessments of cat taxa are initiated by the Cat SG itself. A (re)assessment is initiated immediately if there are indications that the global status of a species or subspecies has deteriorated and may classify for a higher threat status. Usually, every species has to be reassessed every 5–10 years for the IUCN Red List.
As a first step the lead assessor and his/her assessor team (ideally one assessor per range country of the taxon) compile available data and information on the species with regard to its distribution and occurrence, population size and trends, habitats and ecology, use and trade, threats and conservation measures. Contributors provide additional information and data to the assessment but these are not included into the application of the IUCN Red List Categories and Criteria. Based on all this information, the supporting material for the assessment is written and the species is then evaluated against all Red List Criteria to define the appropriate Red List Category for the species. The listing must be properly justified with supporting documentation. The creation of a distribution range map according to the IUCN mapping standards is a key part of the assessment.
The final draft assessment is then sent to the Red List Authority, who organises the review process. Each assessment is reviewed by at least one person, but generally by two or more. Reviewers can be species or Red List experts.
When reviewers and assessors agree with the assessment, it is integrated into the Species Information System of the IUCN and submitted to the Global Mammal Assessment Team at Sapienza University in Rome. They conduct an initial check of the assessment with regard to its consistency and completeness before sending it to the Red List Unit. The Red List Unit does the final check and decides whether or not to publish the assessment on the Red List website.
To ensure that Red List assessments are rigorous and defensible, it is essential to understand the Categories & Criteria and to apply them properly, to provide the necessary supporting information, create a distribution map, check the assessment for consistency and errors and to work with other relevant groups or people doing Red List assessments.
For any questions to Red List assessments and its process, please reach out to Tabea Lanz, Red List Authority Coordinator of the Cat SG: t.lanz@kora.ch
Assessment process – an overview
IUCN Red List Assessment Process
IUCN Red List Guidelines and Documents
M. Lorentz
The IUCN Red List of Threatened SpeciesTM provides many resources and guidelines for conducting Red List Assessments on their website. One of the key documents is the Guidelines for using the IUCN Red List Categories and Criteria. In this document, it is explained how the Criteria should be applied to define to which Category a taxon belongs to. Moreover, they provide detailed explanations of definitions of key terms and examples from different taxonomic groups. The documentation standards and consistency checks for IUCN Red List Assessments and species accounts provides detailed instructions for the documentation of the assessments and lists the required and recommended supporting information which have to go with every assessment for the IUCN Red List. Additionally, it contains the standard checks that have to be done before submitting an assessment to the Red List Unit.
Assessments of taxa at a regional or national level follow generally the same guidelines as for assessments at the global level. However, there are some important additions to take into account, which are addressed in the Guidelines for application of IUCN Red List Criteria at regional and national levels.
The mapping standards and data quality for the IUCN Red List Spatial Data provide guidance on what distribution data are needed for Red List Assessments, on how to map species distribution and what attributes are required and recommended together with every species distribution map.
All documents regarding the IUCN Red List and species assessments are available at the IUCN Red List website.
Online training to get familiar with the Red List assessment process and guidelines has been developed and is accessible for anybody who registers.
The Cat SG has additionally developed guidelines which are based on the IUCN guidelines and following the same principals but are more specifically focused on cat species and provide a detailed overview on the assessment process and the different roles in it.
Figure 1. IUCN Red List Categories
IUCN Red List Categories & Criteria
The aim of the IUCN Red List Categories and Criteria is to provide an explicit, objective and easily and widely understood system for classifying the extinction risk of a taxon that can be applied consistently by different people and which facilitates comparison across different taxa. They provide guidance on how to evaluate different factors which affect the risk of extinction. However, it should be noted that, although the system places species into the threatened categories with a high degree of consistency, the criteria do not take into account the life histories of every species. Hence, in certain individual cases, the risk of extinction may be under- or over-estimated.
Species are evaluated against five Criteria to define in which of the nine Categories they fall into.