GSPC Target 2

Objective I: Plant diversity is well understood, documented and recognized

Objective II: Plant diversity is urgently and effectively conserved

Objective III: Plant diversity is used in a sustainable and equitable manner

Objective IV: Education and awareness about plant diversity, its role in sustainable livelihoods and importance to all life on earth is promoted

Objective V: The capacities and public engagement necessary to implement the Strategy have been developed


Once a plant species is named and recorded, we then want to assess its abundance or rarity in order to know if the species is at risk of extinction. We therefore need to know the species location, distribution and the number of plants or populations of the plant. Threats to plant diversity include loss of habitat due to land use changes, intensive agriculture and urbanisation, unsustainable levels of harvesting, invasive species and ultimately, climate change.

Threat assessments may be desk based, using computer records from previous surveys or involve additional data collection by field work. This process of assessing rarity is known as ‘Red Listing’: species which are rare appear on Red Lists. Global Red Lists are maintained by the International Union for the Conservation of Nature (IUCN) (see

Species shown in the IUCN Red Lists are categorized as: Extinct, Extinct in the Wild, Critically Endangered, Endangered, Vulnerable, Near Threatened, Data Deficient and Least Concern.

An assessment of which species are threatened allows resources for species conservation to be prioritised.

Despite the importance of this target, only a fraction of plant species have so far been assessed in a globally comparable way. However, at the national level, a growing number of countries have completed some form of Red List assessment for their plants.

Download an introduction to Target 2 here.

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Threat status is probably the most commonly used criterion in conservation priority setting and provides an idea of the risk of extinction for any given species.

The conservation status of many plant species has been assessed either through country-level processes and/or international initiatives. These assessments have been made either using the IUCN Red List Categories and Criteria or other systems. A compilation of these evidence-based assessments will provide a useful starting point to guide conservation action. A full assessment of all known plant species to a consistent international standard is the longer term aim.

Although the IUCN Red List Categories and Criteria provide a robust framework for conservation assessments, it is not realistic to aim to assess all plant species using this system by 2020. Instead, it is suggested that a working-list of evidence-based conservation assessments is the only feasible approach to achieving this target at the global level by 2020.  Inclusion of the term 'evidence-based' in the target is intended to make clear that the assessments should be based on data which are verifiable. A variety of evidence-based approaches are acceptable as practical steps towards the achievement of the target.

Achieving this target is essential to ensure that progress towards Targets 7 and 8 is not hampered by a lack of information on which species are under threat.

The implementation of this target relates to Target 19 of the Aichi targets of the Strategic Plan for Biodiversity 2011-2020:

T19: By 2020, knowledge, the science base and technologies relating to biodiversity, its values, functioning, status and trends and the consequences of its loss, are improved, widely shared and transferred, and applied.  

This target also relates to the Convention on the international Trade in Endangered Species of Wild Fauna and Flora (CITES) as CITES requires an assessment for each amendment proposal to its Appendices, as well as for the periodic and significant trade reviews.



The IUCN Red List  Categories and Criteria

The IUCN Red List Categories and Criteria represent the most accepted and widely used method of threat assessment. This is a consistent, transparent, repeatable, quantifiable and standardised system that provides clear guidance on how to evaluate different factors that affect the risk of extinction.

The IUCN Red List Categories and Criteria have undergone extensive review in recent years. This review has produced a clearer, more open, and easy-to-use system. The revised Categories and Criteria (IUCN Red List Categories and Criteria version 3.1) were adopted by IUCN Council in February 2000 and all new assessments and reassessments of taxa on the IUCN Red List must follow this revised system.

Guidelines on how to use the IUCN Red List Categories and Criteria have been developed and are regularly updated; a PDF version of these guidelines is available in English only.

The direct link to the Guidelines PDF is:

Guidelines for Using the IUCN Red List Categories and Criteria

IUCN offers training and support on Red Listing in multiple languages and supports the establishment of national lead institutions for Red Listing, which facilitates the identification of taxonomic experts in the respective countries.

An online resource is available to facilitate communication and knowledge-sharing about national and regional Red Lists, and to act as a centralised point for national and regional Red List data from around the world. This website includes a searchable species database, a library of downloadable documents, a network of individuals involved in national/regional Red Listing around the world, and a discussion forum for specific queries.

The South African National Biodiversity Institute (SANBI) has developed a simple, user-friendly database for Red Listing, which is linked to the IUCN Species Information Service.

The Global Tree Assessment

BGCI is coordinating the Global Tree Assessent which aims to provide conservation assessments of all the world’s tree species by 2020. The assessment will identify those tree species that are at greatest risk of extinction. The goal of the Global Tree Assessment is to provide prioritization information to ensure that conservation efforts are directed at the right species so that no tree species becomes extinct.

A series of  e-learning modules on red list assessments for trees have been produced by BGCI. There are four modules in this series which together offer an introduction to tree red listing for anyone interested in getting involved with red listing of tree species.

Rapid assessment methods

The Royal Botanic Gardens, Kew has developed a rapid assessment tool for the identification of the conservation status of plants based on herbaria specimens and their locations, which can help prioritize species for full IUCN Red List assessment. This tool can be seen here.

Similarly, other approaches to rapid assessments using herbaria specimens developed by New York Botanical Garden and the Smithsonian Institution are described in a poster that can be downloaded here.

National Assessments

Good progress with Red List conservation assessments is being made at the national level, in some cases using nationally developed instruments for assessing extinction risk. (For example, Mexico developed a national method to assess species extinction risk - see Método de Evaluación del Riesgo de Extinción de las Especies Silvestres en México, MER).  A unique South-South partnership involving South Africa, Brazil and Colombia has been established to share experiences and accelerate progress in Red List assessments in mega-diverse countries using the IUCN Red List Categories and Criteria.  This has resulted in the publication of the Brazilian Red data book – a significant contribution to the achievement of Target 2.

General points

It is recommended that national herbaria should be involved in the process of conservation assessments. For example, they could be the focal point for the assessment of national endemic plant species. For plant species whose distribution covers more than one country, the corresponding national herbaria should coordinate with each other to achieve a global conservation assessment. Furthermore large 'northern' herbaria could assist 'southern' herbaria through the repatriation of specimen data information.

While priority should be given to red listing wild plants that contribute directly to human livelihoods (food, medicine, fuel, housing, fodder etc.), rapid assessments of the non-threatened status of the majority of plant species should also be achieved.



Various processes within CITES contribute to Target 2. The Periodic Review and Review of Significant Trade regularly assess biological and trade data of species listed in the Appendices in order to verify that the species is in the correct Appendix and that levels of trade are not detrimental to its survival in the wild.

The CITES trade database, maintained by UNEP-WCMC, represents one of the main sources of information that serves as the basis for the above analysis.



 Tools and resources

Please also check in the database of Tools of Resources for Case Studies relevant to this target.

Guidelines for application of IUCN Red List criteria at regional and national levels: version 4.0

IUCN has developed guidelines on how to apply the IUCN Red List Criteria appropriately for sub-global level assessments. These Guidelines have been reviewed and updated since the first version was published in 2003 


Guidelines for Using the IUCN Red List (505KB)

This document explains how the IUCN Red List Categories and Criteria should be applied to determine whether a taxon belongs in a category of threat, and gives examples from different taxonomic groups to illustrate the application of the criteria. 


How to red list a tree species

This brief describes the major steps required to complete a red list assessment. It aims to help better planning of red list assessments; providing information on what kind of information is needed, who should be contacted or involved and when and in what order you should carry out each step. 


Lessons learnt from assessing a megaflora: the South African experience of red listing >20,000 plant taxa. (261KB)

Between 2004 and 2008, South African botanists completed a comprehensive assessment of the status of the South African flora using the IUCN 3.1 Red List Categories and Criteria. In so doing becoming the first of the world’s megadiverse countries to fully assess the status of its entire flora 


National Red Listing Beyond the 2010 Target (310KB)

This paper by Zamin et al reviews National Red Lists (NRLs) produced globally and analyses existing data gaps in geography and taxonomy. The paper also discusses a correlation between NRL datasets and gross domestic product and vertebrate species richness. 


Plants under pressure

Plants Under Pressure – a global assessment. This is the first report of the IUCN Sampled Red List Index for Plants published by the Royal Botanic Gardens Kew, UK. 



The IUCN Red List of Threatened Species™ is recognized as the most comprehensive objective global approach for evaluating the extinction risk of species and  is the scientific basis underpinning many of the indicators adopted by the CBD for monitoring progress towards the achievement of the GSPC and Aichi Targets.

One critical gap however is that, to date, only a limited number of IUCN Red List assessments are available on the conservation status of plants.  The IUCN Red List presently (March 2018) includes assessments for 24,230 plant species, of which 14,614 (60%) are considered to be threatened with extinction or extinct.  This represents only around 6.5% of known plant species. The sample of plants for which conservation assessments are available is not only small, but also skewed, notably because assessors tend to select species that are likely to be at risk of extinction.

IUCN’s target (based on the IUCN SSC Barometer of Life analysis) is to have 38,500 plants published online on the IUCN Red List by 2020

Sampled analysis

A solution to a potential bias towards species at high risk taken by RBG Kew, was to select a suitably large, random selection of plant species and assess their extinction risk. This representative view has revealed that one in five plant species are estimated to be in the top three ‘threatened’ categories of Critically Endangered, Endangered or Vulnerable. Further assessments of the sample in future years will establish an overall trend in the extinction risk index for plants.

Combining data

To further address the gap in global conservation assessments for plants, Botanic Gardens Conservation International (BGCI), together with partners from the National Red List and the Royal Botanic Gardens, Kew, have assembled all currently available conservation assessments, including data from IUCN, into a single list of conservation assessments for plants. This list was launched in 2017 and is available on-line as the ThreatSearch database.  It presently includes over 242,000 assessments representing over 150,000 taxa  and is the most comprehensive database of conservation assessments for plants.

In January 2017, an analysis of data in ThreatSearch was published by scientists from the Royal Botanic Gardens, Kew and BGCI. This study showed that conservation assessments are now available for a quarter of all known plant species.

The scientists analysed digitally available plant conservation assessments from a range of sources, and then, by reconciling the plants’ scientific names and assessment statuses to predefined standards, have been able to provide, for the first time, a quantitative measure of progress towards GSPC Target 2.  The results of the study show that 21–26% of known plant species have been assessed on a global scale and 20-44% of assessed species are threatened with extinction.

While the results of this study show that considerable progress has been made in assessing the conservation status of plant species, many gaps remain.  For example, the analysis revealed wide gaps in taxonomic coverage, with some families such as Zamiaceae and Magnoliaceae being almost completely assessed, whereas other families such as Orchidaceae, Asteraceae, and Rubiaceae are under-assessed relative to the average.

The greatest challenges in carrying out this study were matching the 241,919 plant conservation assessments to accepted plant species names (vascular plants and bryophytes) and reconciling the different assessments that might have been made for the same species.  In total, the assessments relate to 111,824 accepted species names (matched to The Plant List ), with at least 27,148 and up to 32,542 species being threatened.

Although around one-quarter of a million plant assessments have been compiled, the majority of plants are still unassessed. However, the data set used for this study is accessible online (ThreatSearch ) and it provides a baseline that can be used to directly support plant conservation action. The challenge now is to build on this progress and redouble efforts to document the conservation status of unassessed plants to better inform conservation decisions and conserve the most threatened species.

The full paper is accessible to read and download here:








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