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Description of Data
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Description of Data

The mammal data on the 2008 IUCN Red List includes 5,488 species, 412 subspecies and one 21 subpopulations. The primary focus of the current assessment was at the species level, and all species assessments are complete including all supporting documentation. In analyses of the mammal data on this website only species data are used.

The subspecies assessments on the 2008 IUCN Red List were completed by the relevant IUCN Specialist Group and were not subject to rigorous checks and evaluation by the central coordinating team. Although the IUCN Red List primarily focuses at the species level, subspecies assessments are also accommodated if a Specialist Group also submits a complete species level assessment. Subspecies are usually only submitted for more data-rich species groups such as primates and cats, which also plan conservation at the subspecies level. For subspecies and subpopulations, only the systematic information (see section 1.1.1) and the IUCN Red List assessment (see section 1.1.8) sections were completed. All other information relevant at the subspecies level, such as distribution and population, were incorporated in the relevant species level assessment.

The types of data included for all mammal species in the 2008 IUCN Red List are described below. The process of collecting and reviewing the data and making the assessments is described in detail in the mammal assessment process.

 

1. Data Types

1.1 What data are available from the searchable online database?

The following data are provided for each species in the online searchable database:

1.1.1. Systematics

For each species, data were was collected on species, genus, family, order, taxonomic authority, commonly used synonyms, English and other common names (if any), and taxonomic notes (if needed, normally used to clarify difficult or confusing issues). The default taxonomy for mammals on the IUCN Red List is the 3rd edition of Mammal Species of the World – A Taxonomic and Geographic Reference (see references section below for details). However, as the text for Mammal Species of the World was effectively completed in 2003, it has been necessary to depart from this taxonomy in well-justified circumstances. In such cases, and except in very exceptional circumstances, any newly recognized species (either newly described or newly split) or any other proposed taxonomic change had to be published in a peer-reviewed journal or other authoritative taxonomic work (e.g., a major faunistic treatise). The current mammal taxonomy in the 2008 IUCN Red List is current as of December 2007; and some more recently proposed changes will be included in subsequent updates of the database.

The IUCN Red List is not intended to be a definitive taxonomic source, but it strives to be taxonomically coherent and consistent at all ranks. Our higher-level classification largely follows that of Mammal Species of the World, but again deviates in some respects. At the level of Order, for example, the primary deviation is recognition of the Cetartiodactyla, to include the previously recognized orders Cetacea (whales, dolphins and porpoises) and Artiodactyla (bovids, hippos, giraffids, deer and relatives). While a case can be made for continuing the use of the name Artiodactyla for this clade, we have decided to use the now established Cetartiodactyla to avoid confusion.

1.1.2. General Information

General text information on: geographic range, population (usually a subjective assessment of abundance or rarity in the absence of quantitative information), habitat and ecology (including, in particular, habitat preferences and ability to adapt to anthropogenic disturbance, as well as any particular biological traits that may make a species particularly vulnerable), major threats and conservation measures (in particular noting occurrence in protected areas).

1.1.3. Distribution Map

A geographic distribution map of the Extent of Occurrence for each species was completed for each mammal in ESRI shapefile format (ArcView GIS 3.x and ArcGIS 9.x). The maps take the form of broad polygons that join known locations. A species' distribution map can consist of more than one polygon where there is an obvious discontinuity in suitable habitat. For some range-restricted taxa, we have tried to map distribution ranges with a higher degree of accuracy, sometimes down to the level of individual subpopulations.

The IUCN Red List includes distribution maps for 5,396 of the 5,488 mammals that were assessed (two species remain in the category Not Evaluated, namely Capra hircus and Ovis aries). Maps are missing for all Extinct species and typically for some Data Deficient species that are known only from non-specific type localities. These spatial data used the maps collected by Sechrest (2003) as a starting point for some species, and were then significantly improved in accuracy and detail through expert editing.

As well as the map included with each individual species account, the individual shapefiles (.shp) are also available for download in batches by family. These require specialized GIS software to open. A description of the attributes for these shapefiles is available here.

A list of countries of occurrence is given, noting whether it is native extant, extirpated, introduced or re-introduced.

1.1.4. Habitat Preferences

Each species is coded against a standardized list of habitats, the IUCN Habitats Classification Scheme, and coded for suitability and relative importance.

1.1.5. Major Threats

Each species is coded against a standardized list of threats, the IUCN Threats Classification Scheme, and coded for whether the threat is acting in the past, present or future, or is an ongoing threat.

1.1.6. Conservation Actions

Each species is coded against a standardized list of conservation actions, the IUCN Conservation Actions Classification Scheme, and coded for whether this measure is "In Place" or "Needed".

1.1.7. Utilisation

Each species is coded against the IUCN Utilisation Authority File (focusing on the purpose/type of use, the primary forms removed from the wild, and the source of specimens in commercial trade).

1.1.8. Red List Assessment

Based on the information above, the 2001 IUCN Red List Categories and Criteria (Version 3.1), were applied to make an assessment of extinction risk for each mammal species. The IUCN Red List Categories include eight different categories of threat (Fig. S1): Extinct (EX), Extinct in the Wild (EW), Critically Endangered (CR), Endangered (EN), Vulnerable (VU), Near Threatened (NT), Least Concern (LC) and Data Deficient (DD). A species qualifies for one of the three threatened categories (CR, EN, or VU) by meeting a critical threshold for that category in one of the five different available criteria (A-E). The criteria are designed to be objective, quantitative, repeatable, and to handle uncertainty.

Each IUCN Red List assessment is accompanied by a rationale that explains the justification behind the assessment, the reason for any change from previous assessments (i.e., genuine change in species' status, or non-genuine due to new or better information available, incorrect information used previously, taxonomic change affecting the species, previously incorrect application of the IUCN Red List Criteria), the current population trend (i.e., increasing, decreasing, stable, unknown), date of assessment, names of assessors and evaluators, and any notes relating to IUCN Red Listing (e.g., any important issues in deciding the category).

Assessments are done at the species level, integrating the information across all populations and/or subspecies. Threat categories therefore reflect the overall conservation status of the species, which may for example be of Least Concern despite particular populations/subspecies being highly threatened. In some cases, subspecies and/or populations are also assessed individually, but these results are not included in the statistics and analyses presented here.

1.1.9. Bibliography

A listing of important references for each species.