Organization of Information

Introduction

Documentation of Species

Taxonomy

Assessment Information

Distribution

Summary Documentation

Detailed Documentation

Links to Other Sources

Data Sources

Extinct and Extinct in the Wild Species

Subspecies, Varieties and Subpopulations

Taxa Removed from the Red List (Synonyms)

Distribution Information

Countries and Sub-countries

Doubtful Distributions and Vagrants

Aquatic Distributions

Introductions, Reintroductions and Extinctions

Subpopulations

Summary of the Distribution Codes Used

Introduction

Before 2000 the IUCN Red List was produced in book format. However, since 2000 the Red List has only been available electronically. The reasons for this departure are simple:

  • The decision to incorporate plants and animals into a single Red List, rather than treating them separately, meant that the total species coverage more than doubled in 2000, and continues to increase with each update of the Red List.
  • The 2000 Red List marked the start of a process to document all species listed. This documentation greatly increases the size but also the utility of the Red List.
  • The IUCN Red List now makes better use of the electronic medium as it provides a wider audience with easy access to the information.
  • The Red List is updated at least every two years and increasingly is updated annually, and so the production of a book for each update would be too prohibitive both in terms of time and cost.
The IUCN Red List of Threatened Species is available only as an electronic version on the World Wide Web. A CD-ROM version of the Red List was produced in 2000 and funds permitting, a new version will be produced in the future. The information presented is based on data extracted from the SSC Species Information Service (SIS) Red List database maintained by the IUCN SSC Red List Programme Office in Cambridge, UK. The information provided here covers all taxa that have been assigned an IUCN Red List Category with the exception of those designated as Not Evaluated (NE). All the assessments presented, except those for geographically isolated subpopulations or stocks, are for the taxon (species, subspecies or variety) as a whole (i.e. they indicate the global risk of extinction). No national or regional Red List assessments are included, except for national extinctions (where known) and an occasional note about national or sub-national status in one of the documentation fields.

Documentation of Species

The SSC Red List Programme has developed a set of minimum documentation requirements that were introduced in 2000. Anyone making submissions for inclusion on the Red List is requested to provide (in addition to the usual details about name, status, criteria and distribution) a justification to support the listing; a map of the extent of occurrence; a list of the major habitats the species is found in; what the major threats are; an indication as to whether the species' population trend is increasing, decreasing, stable or unknown; what conservation actions are in place or are needed; and information on the utilization of the species. Non-mandatory information is also collected on life history attributes, the value of species for human livelihoods and the importance of species to ecosystem processes. If the taxon assessed falls within the jurisdiction of an appointed Red List Authority then it will be referred to them for evaluation (for further details about Red List Authorities and how to submit assessments see the IUCN/SSC Red List Programme and the Red List Assessment Process).

The documentation on the Detailed Results page for each taxon may include some or all of the following information under the headings indicated:

Taxonomy

  • Higher taxonomy details are shown for Kingdom, Phylum, Class, Order and Family.
  • Scientific name (genus and species) including authority details wherever possible. (Note: for animals the date of description is usually shown, but for plants this is not the case).
  • Taxonomic notes are included when there are particular problems or issues. These notes may also indicate taxonomic changes that will be made in future updates. A number of taxonomic notes also include generic and species synonyms.
  • Synonyms includes names that appeared in past Red Lists that are no longer accepted as being correct, names that were incorrectly spelt in previous Red Lists (orthographic errors), or alternative names that are still in common use.
  • Common names in English (E), French (F) and Spanish (S) only. There is no attempt to indicate any preferred common names.
  • Under the species assessments, links are provided to any infra-specific assessments that may exist (i.e., subspecies, variety or subpopulation assessments)
  • The Taxonomy section under the subspecies and varieties provides extra details on the scientific names for the taxa and their authority details.

Assessment Information

Distribution

  • Countries of occurrence and sub-country units for large countries and islands far from mainland countries (see below).
  • Occurrence in marine regions and inland water bodies or systems (see below).

Summary Documentation

Detailed Documentation

  • General notes about range; population; habitat and ecology; threats; what conservation measures (or actions) are in place or needed; and comments on the utilization of the taxon. These notes may include links to PDF files with further supporting documentation.
  • A map of the extent of occurrence (these maps are currently only available for the following taxa: all amphibian species; most threatened birds; Mediterranean reptiles and freshwater fishes; and selected East African freshwater fishes, molluscs and dragonflies).

Links to Other Sources

  • Links to other web sites that may contain further information and images of the taxon concerned.

Data Sources

  • The list of references (published and unpublished) used for the assessment and the supporting documentation.

The degree of documentation achieved is extremely variable across the list, but an increasing number of species are meeting the minimum requirements. In a growing number of cases the amount of documentation is substantial, hence to allow users easier navigation through the documentation, the information described above has been grouped under five major headings (Summary, Distribution, Other Documentation, References, Comprehensive) presented as tabs across the top of each Detailed Results page. The Comprehensive tab provides the full documentation for the taxon, whereas the other tabs provide subsets of the information as indicated.

For anyone wishing to submit a Red List assessment for inclusion on the Red List please see the details given under The Red List Assessment Process.

Extinct and Extinct in the Wild Species

For Extinct species (and infra-specific taxa), extra documentation is required indicating the effective date of extinction, the causes of the extinction and the details of surveys which have been conducted to search for the species. The starting date for the inclusion of extinctions was previously set at 1600 AD, but this has been moved back to 1500 AD to be in line with the starting date used by the Committee on Recently Extinct Organisms. An attempt has been made to collate whatever information is available on each Extinct species and this is presented in the various documentation fields.

Subspecies, Varieties and Subpopulations

Although the name IUCN Red List of Threatened Species implies that the primary focus is at the species level, the IUCN Red List also includes assessments that are done at the infra-specific or subpopulation levels. Ideally, for such taxa to be included in the Red List, the global status of the species itself should be assessed. In most instances this is the case and generally these are assessed as Least Concern (LR/lc or LC). There are some cases, however, especially amongst the plants where this has not been done and it may well be that some of these species warrant a threatened status. For subpopulations (also called stocks), only geographically isolated subpopulations, between which there is little genetic exchange (typically one migrant individual or gamete per year), are included on the IUCN Red List.

In the 2000 version of the Red List, all searches produced combined results for species, subspecies, varieties and subpopulations. In many cases users only wanted species-level information and if the lists were very long this was often difficult to extract. The default search options now provide results at the species level only. Searches for subspecies, varieties and subpopulations have to be specified separately. If assessments for subspecies, varieties or subpopulations are available, these are clearly indicated from the detailed results pages of the species concerned.

Taxa Removed from the Red List (Synonyms)

The Red List is highly dynamic with species moving on and off for a variety of reasons. The main reasons for removals from the list are changes in taxonomy. All changes are tracked, so that a complete audit trail is kept for each taxon name that ever appears on the Red List. Taxa removed from the Red List for taxonomic reasons (i.e., they are considered synonyms of other taxa) are searchable (searches will indicate the synonyms found under their accepted/correct names); and the synonym/s are listed on the Detailed Results page for the accepted taxon. The list of synonyms also includes misspellings (orthographic errors). It is not intended that the IUCN Red List will maintain an exhaustive synonymy for all taxa on the list, however, commonly used synonyms are often included. Any synonyms listed under the taxonomic notes are generally not searchable.

Distribution Information:

Countries and Sub-countries

Distribution is recorded in terms of country names following the 5th edition (and subsequent web updates) of the ISO-3166-1 standard (ISO 1997). Unless geographically very remote from each other, islands and other territories are included with the parent country. In the case of species that inhabit islands significantly distant from the mainland, the island name is given in parentheses (e.g., Spain (Canary Islands)). The naming of such islands follows edition 2 of the World Geographical Scheme for Recording Plant Distributions (Brummitt et al. 2001) prepared for the International Working Group on Taxonomic Databases (TDWG). The TDWG geographic system also provides a standard set of Basic Recording Units (BRU) that are sub-country units based on provinces or states. The BRU's are used to subdivide very large countries like Australia, Brazil, China, South Africa, the Russian Federation and the United States of America, etc. into smaller more conveniently sized units for recording distributions. This system has been adopted for the IUCN Red List wherever possible. Most plant taxa on the Red List have had their distributions recorded down to BRU level where appropriate, but unfortunately sub-country information is still lacking for most of the animal species. Hence this feature is not currently searchable. Each country or territory has also been assigned to a single geographic region to enable users to search by larger geographic areas. (View the list of Countries by Regions).

Geopolitical events during recent years may have led to some inconsistency or errors in the distribution information provided. Within reasonable limits every effort has been made to determine which of the new nations that were part of the former Czechoslovakia, Yugoslavia and USSR support species previously attributed to the larger unit. There may be some species in the Red List that have still not been fully resolved. Adherence to the ISO system also creates some problems, as there is often a time lag between a political change and a new ISO code being allocated for the new country. The version of the ISO codes used for example, maintains Hong Kong and Macao as separate units.

Doubtful Distributions and Vagrants

The distributions of some species in certain countries have not been confirmed. These are indicated as possibly doubtful occurrences by the inclusion of a '?' after the country name. These instances are distinct from vagrant distributions that are usually displayed separately with a [vag] or [vag?] flag after the country name. But combinations of doubtful country occurrences and vagrants plus doubtful countries and dubious vagrants are also possible. So care should be taken when using the distribution information for subsequent analyses. Likewise, for a number of very widespread Least Concern taxa, the list of country occurrences may be incomplete or in some instances not even recorded (e.g., Mus musculus ) because such taxa are virtually cosmopolitan. Please note that the results presented in the published analyses of the Red List data (Baillie et al. 2004, Hilton-Taylor 2000), do not include questionable distribution records and vagrant distributions. Note that summary statistics tables do not include any questionable distribution records and records of vagrants, so that the results of any searches on the Red List web site should match the figures in the summary tables.

Aquatic Distributions

For marine species, country records have been provided wherever possible. This information has been derived from a number of sources, e.g. FishBase and the many FAO publications. Any species without a country name in the Red List is not included in any of the analyses or tables presented. For some marine species, especially those that are most strictly marine, their distributions are also shown as generalized ranges in terms of the FAO Fishing Areas, indicated as follows (e.g., Atlantic-eastern central). For many inland water species, usually those restricted to a single water system, inland water ranges are also given with a clear indication from the name if it is a river or a lake. In a few instances, a second river name (e.g. Colorado River, Concho River) indicates a section of the drainage in which the species occurs. In most cases, the countries in which these freshwater species occur are also recorded, but there are a few instances (e.g., cichlid fish in Lake Victoria), where the precise country distribution is unknown, so the only distribution information is the Lake name.

Introductions, Reintroductions and Extinctions

In most cases where a species is known to have been introduced or reintroduced to a country, this is indicated by an [int] or [re-int] after the country name in the distribution text. Note that for searches on threatened species in a specific country or group of countries, the introduced species are excluded from the results (and also from the summary statistics tables). Whereas a search for a particular threatened species, will list the countries where it has been introduced. Where populations are known or suspected to have been extirpated from a country, this is indicated by [RE] or [RE?] for Regionally Extinct or possibly Regionally Extinct.

Subpopulations

The Red List contains assessments for some stocks or geographically isolated subpopulations. In the 1996 Red List these were indicated by (S) after the species name, but this created confusion in some cases, so a geographic name is now given directly after the name of the species e.g., Balaena mysticetus (Spitsbergen stock).

Summary of the Distribution Codes Used

? Doubtful country or sub-country occurrence.
[vag] Taxon is a vagrant in the country or sub-country unit.
[vag?] Taxon is a doubtful vagrant in the country or sub-country unit.
[int] Taxon has been accidentally or deliberately introduced into that country or sub-country unit (the area of introduction was not part of its known historic range).
[int?] Taxon has possibly been accidentally or deliberately introduced into that country or sub-country unit (the area of introduction was not part of its known historic range).
[re-int] Taxon has been deliberately re-introduced into an area that was formerly part of its known historic range in that country or sub-country unit or a deliberate introduction (termed a 'benign introduction') into an area outside of it historic range specifically for conservation purposes.
[re-int?] Taxon has possibly been deliberately re-introduced into an area that was formerly part of its known historic range in that country or sub-country unit or a deliberate introduction (termed a 'benign introduction') into an area outside of it historic range specifically for conservation purposes.
[RE] The taxon is 'Regionally Extinct' in the country or sub-country unit.
[RE?] The taxon is possibly 'Regionally Extinct' in the country or sub-country unit.