The IUCN Red List explained

Monday, February 26, 2018 by CapeNature

 

The International Union for Conservation of Nature (IUCN) Red List is a comprehensive inventory which sets criteria to evaluate the extinction risk of a range of biological species and subspecies.

There are nine IUCN Red List categories:

  • Extinct (EX) – No known individuals remaining
  • Extinct in the wild (EW) – Known only to survive in captivity, or as a naturalized population outside its historic range
  • Critically endangered (CR) – Extremely high risk of extinction in the wild
  • Endangered (EN) – High risk of extinction in the wild
  • Vulnerable (VU) – High risk of endangerment in the wild
  • Near threatened (NT) – Likely to become endangered in the near future
  • Least concern (LC) – Lowest risk (Does not qualify for a more at-risk category; widespread and abundant taxa are included in this category.)
  • Data deficient (DD) – Not enough data to make an assessment of its risk of extinction
  • Not evaluated (NE) – Has not yet been evaluated against the criteria

The International Union for the Conservation of Nature (IUCN) established the Red List in 1963 to objectively categorise the probability of extinction for every species on the planet. Assessments are carried out through vast networks of scientists, conservationists and other stakeholders pooling their knowledge. Red Lists have become the backbone of global conservation as a unified and standardised tool to measure biodiversity loss and inform policy and conservation planning.

Red List – South African Mammals

The Red List of Mammals of South Africa, Swaziland and Lesotho 2016 was produced by the EWT and SANBI, with collaboration from the universities of Cape Town and Pretoria’s MammalMAP and the IUCN Species Survival Commission (SSC), provincial and national conservation agencies, museums and universities.

Click here to download the Red List of Mammals of South Africa, Swaziland and Lesotho 2016.

The threats that mammals face are broad and complex, and conservationists must tackle multiple ongoing challenges to address them effectively. Habitat loss from agricultural, industrial (including renewable energy) and human settlement expansion continues to impact on key habitats, such as grasslands and wetlands. This expansion also fragments remaining habitats, with most of our larger species left isolated in fenced-off protected areas. Compounding this, climate change is projected to increase drought conditions in the western parts of South Africa.

Agricultural, industrial and settlement expansion also tend to increase the rates of damaging human activities, such as fuel wood harvesting, overgrazing, pollution, electric fence erection and water abstraction, that continue to threaten species that rely on productive and connected habitats such as grasslands, wetlands and riparian corridors. This impacts many species, including the Riverine Rabbit, African Striped Weasel and Spotted-necked Otter.

But all is not doom and gloom. South Africa boasts some real conservation success stories, often driven by cooperation between conservationists and the private sector. The Bontebok, for example, was saved from the brink of extinction by a few prescient landowners in Bredasdorp, and today both the Cape Mountain Zebra and the South African populations of African Lion have been listed as Least Concern, due largely to their expansion on private protected areas. Innovative interventions such as the Badger Friendly Honey Programme, livestock guarding dogs and biodiversity stewardship schemes are beginning to have a positive impact on many species.

Red List – South African plants

One in four South African plant species is of conservation concern. Major threats to the South African flora are identified in terms of the number of plant taxa Red-Listed as threatened with extinction as a result of each threat including the following:

  • Habitat loss, which includes the irreversible conversion of natural vegetation for infrastructure development, urban expansion, crop cultivation, timber plantations and mines is by far the most severe threat to South African plants, affecting more than 1600 taxa.
  • Invasive alien plant species outcompeting indigenous plant species.
  • Habitat degradation includes threats such as overgrazing, inappropriate fire management (which may be either too frequent, too infrequent or out of season fires) and clearing of woody shrubs and trees from forests and savannas. These threats may appear to leave natural vegetation intact, but causes a disturbance and breakdown of essential ecosystem processes, resulting in the loss of sensitive species.
  • Harvesting is the unsustainable, destructive removal of plants and plant material such as tree bark for local and international trade (medicinal as well as ornamental) as well as for materials for construction and crafts.
  • Demographic factors include species that are threatened as a result of high risk population dynamics such as small population size, poor breeding success, and skewed male-female ratios.
  • Pollution indicates species that are threatened by water, land or air pollution, typically species affected by harmful industrial and agricultural chemicals such as fertilizer, pesticides and herbicides.
  • Changes in species dynamics indicate species that are threatened as a result of disturbances of the natural interactions of native species such as the loss of pollinators or dispersers. Often severe habitat disturbance may give a few native species a competitive advantage, and they then act in the same way as alien invasive plants, outcompeting and replacing other sensitive native species.
  • Climate change has been identified as a threat to only a small number of plants, particularly because the potential impact of climate change on different species is not well understood and not easy to predict.
  • Natural disasters include threats such as droughts and floods.

Click here to for more details on the Red List of South African plants.

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