The updated IUCN Red List of Ecosystems Guidelines provides enhanced global standards for ecosystem risk assessment

The IUCN Red List of Ecosystems Thematic Group is excited to announce the release of the updated Guidelines for the Application of IUCN Red List of Ecosystems Categories and Criteria (Version 2.0). This essential document provides the global standard for ecosystem risk assessment and serves as a framework for monitoring the status of the world’s ecosystems.

The IUCN Red List of Ecosystems Categories and Criteria offer a consistent method for assessing the risk of ecosystem collapse. This critical tool supports conservation, resource use, and management decisions by identifying ecosystems most at risk of biodiversity loss. By focusing on a level of biological organization above species, it offers unique and valuable insights to inform biodiversity conservation decision-making and action. The categories and criteria are designed to be widely applicable across ecosystem types and geographical areas, transparent, scientifically rigorous, and easily understood by policymakers and the public.

The guidelines have been extensively updated by an international team of RLE specialists, incorporating major enhancements to ensure the rigorous application of the Red List criteria. The new guidelines now include extensive technical advice on how to assess ecosystem degradation under criteria C and D, as well as new sections for assessing risks related to climate change and ecosystem fragmentation. Notably, it provides new guidance on making the most of quantitative data and expert knowledge, incorporates recent research on the performance of range size measures, and updates ecosystem classification and typologies, including the IUCN Global Ecosystem Typology. The document also offers new guidance on ecosystem collapse diagnosis, introduces more comprehensive definitions of technical terms, and includes updates on the assessment of semi-natural and anthropogenic ecosystem types. These improvements ensure that the guidelines remain a robust and comprehensive tool for ecosystem risk assessment.

The guidelines feature eight categories and five criteria for assessing the risk of ecosystem collapse. The categories range from Collapsed (CO) to Not Evaluated (NE), while the criteria (A–E) assess various symptoms of ecosystem collapse, such as declining distribution, restricted distribution, environmental degradation, and disruption of biotic processes.

To support the correct application of these categories and criteria, the guidelines offer detailed information on their development and scientific foundations, appropriate input data, interpretation of listing criteria, and assessment methods. Sections cover the assessment process, reduction in geographic distribution, restricted geographic distribution, environmental degradation, disruption of biotic processes, and quantitative risk analysis, among other topics.

To access the updated guidelines, click here.

Written by: Emy Miyazawa