Endangered & Threatened Species
Author: Yolan Friedmann ~ Endangered Wildlife Trust (EWT)
( Article Type: Overview )
Red Data Books and Lists are IUCN (World Conservation Union), Species Survival Commission (SSC) products and were initiated in 1963 by Sir Peter Scott as a means of preventing extinction through an easily understood method of identifying, documenting and creating awareness of threatened species. Red Data Books have since become a means of documenting and highlighting biodiversity losses at the species level and are important tools globally for guiding the conservation activities of governments and conservation organisations. Red Data Books are widely recognised as the most comprehensive, scientific evaluation of the conservation status of plant and animal species as well as measures of the success or failure of various conservation initiatives.
The identification of species whose existence is threatened has since become a key element in the process of defining global and regional priorities for conservation and guiding the conservation efforts of governments and NGOs.
Red Data Books and Lists categorise species according to levels of threat and risk of extinction and serve to direct conservation efforts, affording threatened species a greater level of protection, highlighting species in most danger of extinction and acting as a global index of biodiversity loss. Red Data Books and Red Lists use a set of criteria to evaluate the extinction risk of species and subspecies and assign categories of threat. The criteria are relevant to all species and all regions of the world.
The criteria used to compile Red Data Books have been updated frequently and the latest Red Data Books and Lists are based on the most up-to-date criteria, version 3.1 endorsed by the IUCN in 2001 (click here for the latest Reda Data Books and Lists ).
There are nine categories in the IUCN Red List system: Extinct, Extinct in the Wild, Critically Endangered, Endangered, Vulnerable, Near Threatened, Least Concern, Data Deficient and Not Evaluated (see Figure 1). All species or groups of species (taxa) that are listed as Critically Endangered, Endangered and Vulnerable are described as ‘threatened’. Classification into these categories is through a set of quantitative criteria that are based on biological factors that include rate of decline, population size, area of geographic distribution, and degree of population and distribution fragmentation.
A species is listed as Extinct when there is no reasonable doubt that the last individual has died and when exhaustive surveys in known and/or expected habitat, at appropriate times (diurnal, seasonal, annual), throughout its historic range have failed to record an individual.
Extinct in the Wild (EW)
A species is listed as Extinct in the Wild when it is known only to survive in cultivation, captivity or as a naturalised population outside the previous range. A species is presumed Extinct in the Wild when exhaustive surveys in known and/or expected habitat, at appropriate times (diurnal, seasonal, annual), throughout its historic range have failed to record an individual.
Critically Endangered (CR)
A species is listed as Critically Endangered when the best available evidence indicates that, according to application of the criteria, it is considered to be facing an extremely high risk of extinction in the wild.
A species is listed as Endangered when the best available evidence indicates that, according to application of the criteria, it is considered to be facing a very high risk of extinction in the wild.
A species is listed as Vulnerable when the best available evidence indicates that, according to application of the criteria, it is therefore considered to be facing a high risk of extinction in the wild.
Near Threatened (NT)
A species is listed as Near Threatened when it has been evaluated against the criteria but does not qualify for Critically Endangered, Endangered or Vulnerable now, but is close to qualifying for or is likely to qualify for a threatened category in the near future.
Least Concern (LC)
A species is listed as Least Concern when it has been evaluated against the criteria and does not qualify for Critically Endangered, Endangered, Vulnerable or Near Threatened. Widespread and abundant species or group of species are included in this category.
Data Deficient (DD)
A species is listed as Data Deficient when there is inadequate information to make a direct, or indirect, assessment of its risk of extinction based on its distribution and/or population status. A species in this category may be well studied, and its biology well known, but appropriate data on abundance and/or distribution are lacking. Data Deficient is therefore not a category of threat. Listing of species in this category indicates that more information is required and acknowledges the possibility that future research will show that threatened classification is appropriate.
Not Evaluated (NE)
A species is listed as Not Evaluated when it has not yet been evaluated against the criteria.
A distinction is to be made between a ‘global’ assessment and a ‘regional’ assessment. Global assessments consider the status of the species or groups of species throughout its range globally and regional assessments consider the status of a species within the boundaries of a region, for example a country, only. Thus the status of a species globally may differ substantially from its regional assessment. National boundaries are often irrelevant to populations, so a species inhabiting a country may not have a high extinction risk when the population as a whole is considered, but a fragment of the population that occurs in the country in question may indeed be facing extinction.
Red Data Books and Lists may be compiled by any organisation using the Red List Criteria accurately and appropriately, and in South Africa several organisations are involved with regionally assessing the extinction risk of various species according to the Red List Criteria. The Endangered Wildlife Trust, with funding from Vodacom and the NRF, produced the Red Data Book for the Mammals of South Africa (2004), which involved a full assessment of 295 of South Africa’s terrestrial and marine mammals.
The results were as follows:
Of the 295 South African mammal species and subspecies evaluated, 57 (19%) were assigned threat categories (Critically Endangered, Endangered and Vulnerable) according to the IUCN Red List criteria (version 3.1).
These are divided into:
- 10 (3%) Critically Endangered
- 18 (6%) Endangered
- 29 (10%) Vulnerable
- 53 (18%) Data Deficient
- 38 (13%) Near Threatened
- 147 (50%) Least Concern
Other organisations are also involved with assessing the extinction risk of various species in South Africa, for example, the Red Data Book of the Frogs of South Africa, Lesotho and Swaziland was published by the Avian Demography Unit and the Smithsonian Institution (2004) and the Birds were assessed by Barnes (2000).
The 10 Critically Endangered mammals in South Africa, include (in alphabetical order):
- Black Rhinoceros – arid ecotype ~ Diceros bicornis bicornis
- De Winton's Golden Mole ~ Cryptochloris wintoni
- Juliana’s Golden Mole ~ Neamblysomus julianae (Pretoria subpopulation)
- Ongoye Red Squirrel ~ Paraxerus palliatus ornatus
- Rendall's Serotine Bat ~ Neoromicia rendalli
- Riverine Rabbit ~ Bunolagus monticularis
- Rough-haired Golden Mole ~ Chrysospalax villosus
- Short-eared Trident Bat ~ Cloeotis percivali
- Van Zyl’s Golden Mole ~ Cryptochloris zyli
- Visagie’s Golden Mole ~ Chrysochloris visagiei
Seven of the 10 Critically Endangered mammals are endemic to South Africa (found nowhere else in the world).
Of the 18 Endangered mammals, 33% are endemic to South Africa.
The 18 include:
- African Wild Dog ~ Lycaon pictus
- Antarctic ‘True’ Blue Whale ~ Balaenoptera musculus intermedia
- Cape Mole-rat ~ Georychus capensis (KZN subpopulation)
- Damara Woolly Bat ~ Kerivoula argentata
- Four-toed Elephant-shrew ~ Petrodromus tetradactylus
- Gunning’s Golden Mole ~ Neamblysomus gunningi
- Hartmann’s Mountain Zebra ~ Equus zebra hartmannae
- Indian Ocean Bottlenose Dolphin ~ Tursiops aduncus (migratory subpopulation)
- Marley’s Golden Mole ~ Amblysomus marleyi
- Oribi ~ Ourebia ourebi
- Robust Golden Mole ~ Amblysomus robustus
- Samango Monkey ssp. ~ Labiatus Cercopithecus mitis labiatus
- Sclater’s Forest Shrew ~ Myosorex sclateri
- Southern Elephant Seal ~ Mirounga leonina
- Swinny’s Horseshoe Bat ~ Rhinolophus swinnyi
- Tonga Red Bush Squirrel ssp. ~ Paraxerus palliatus tongensis
- Tsessebe ~ Damaliscus lunatus lunatus
- White-tailed Rat ~ Mystromys albicaudatus