Assessing and managing risks to ecosystem biodiversity

Ecosystem conservation is important for biodiversity and for human well-being. Understanding the relative risks to ecosystems is fundamental to well-informed ecosystem management. The IUCN Red List of Ecosystems protocol provides an adaptable framework for risk assessment across terrestrial, subterranean, freshwater and marine ecosystems. I review a series of detailed case studies, published in this special edition of AustralEcology, that apply the Red List of Ecosystems criteria to a broad range of ecosystem types. These studies show that detailed risk assessments are especially valuable as forerunners to strategic ecosystem management. Key components of Red List assessments that contribute to development of management strategies include critical diagnosis of trends and their causes, identification of dependencies that influence ecosystem responses to environmental change and selection of ecosystem-specific diagnostic variables that can be useful monitoring tools for evaluating the performance of management. Ecosystem Red List assessments are crucial to regulatory processes under environmental legislation in Australia and other countries. The IUCN Red List of Ecosystem criteria will help improve the scientific rigour of statutory listings and could also provide a unifying framework for the suite of listing processes that differ among jurisdictions for historical reasons. When integrated with a comprehensive ecosystem typology, ecosystem Red List assessments can also provide critical input into systematic conservation planning. The case studies demonstrate a range of analytical approaches to risk assessment framed to accommodate data of varying quality and abundance. I conclude by exploring opportunities and requirements for a systematic continental-scale Red List assessment of Australian ecosystems.