Burning vegetation in Madagascar (Itremo)
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Kew’s plant assessment unit

A focal point for extinction risk assessments at Kew.

Objectives and outputs

Increasing the number of species on the Red List

Identifying species at risk is a central goal for conservation. In the face of accelerating biodiversity loss and limited resources, assessment of the extinction risk of species is essential for conservation priority-setting. These assessments can be used to assist governments and conservation organisations to prioritise and guide effective conservation action and inform policy makers.

The IUCN Red List of Threatened Species™ represents an objective, rigorous and internationally accepted methodology for assessing the extinction risk of species. It is globally recognised as a key conservation tool but currently covers just 6% of the 380,000 known species of plants, and has a growth rate which cannot keep pace with the c. 2,000 species described as new to science each year. In 2016 a five-year collaboration between Toyota and IUCN was initiated which aims to deliver critically important assessments of wild species for The IUCN Red List of Threatened Species™. The collaboration aims to deliver at least 28,000 assessments by 2020 which will significantly increase the knowledge available on the conservation status of less well-represented groups on the Red List, such as plants, fungi, freshwater fish, invertebrates, marine and reptile species.

Kew’s role

As part of this five-year collaboration, the Royal Botanic Gardens, Kew created a Plant Assessment Unit (PAU), where dedicated staff provide a focal point for Kew’s scientists working on conservation assessments. Addressing the need to accelerate the assessment of species in tropical regions, the team support the preparation and publication of extinction risk assessments on the IUCN Red List.

The Royal Botanic Gardens, Kew can provide unique taxonomic expertise and data acquired over decades to use as the basis for conservation assessments. With the help of Kew scientists, over the five years, we plan to add over 4,000 species to the Red List. Assessments will range from global assessments of major groups to studies focused on the endemic species of conservation concern in a particular country. These will include a global assessment of Coffea, which ranks second only to oil in terms of value of globally traded commodities; a global assessment of Cola, an African tree genus which includes the source of the 'secret' ingredient in popular soft drinks and a global assessment of Myrcia, a Neotropical genus of trees and shrubs which forms an important component of the diversity in some of Brazil's most threatened habitats.

Illustrations of Coffea arabica (Köhler 1883-1914), Cola acuminata (Köhler 1897) and Myrcia amazonica (Stahl 1883-1888).

Partners and collaborators


  • Toyota


  • IUCN


Brummitt, N.A., Bachman, S.P., Griffiths-Lee, J., Lutz, M., Moat, J.F., Farjon, A., Donaldson, J.S., Hilton-Taylor, C., Meagher, T.R., Albuquerque, S. & Aletrari, E. (2015). Green plants in the red: a baseline global assessment for the IUCN sampled Red List Index for plants. PloS ONE 10(8), p.e0135152.

IUCN (2012). IUCN Red List Categories and Criteria: Version 3.1. Second edition. Gland, Switzerland and Cambridge, UK: IUCN. iv + 32pp. Available online

Nic Lughadha, E., Walker, B.E., Canteiro, C., Chadburn, H., Davis, A.P., Hargreaves, S., Lucas, E.J., Schuiteman, A., Williams, E. Bachman, S.P., Baines, D., Barker, A., Budden, A.P., Carretero, J., Clarkson, J.J., Roberts, A. & Rivers, M.C. (2019). The use and misuse of herbarium specimens in evaluating plant extinction risks. Phil. Trans. R. Soc. B 374(1763). Available online.

Stuart, S.N., Wilson, E.O., McNeely, J.A., Mittermeier, R.A. & Rodríguez, J.P. (2010). The barometer of life. Science 328(5975), pp.177-177.